content: package com.alipay.api.internal.util.file;
  
  import java.io.*;
  import java.net.*;
  import java.nio.ByteBuffer;
  import java.nio.channels.ReadableByteChannel;
  import java.nio.channels.Selector;
  import java.nio.charset.Charset;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.List;
  
  /**
   * General IO stream manipulation utilities.
   * <p>
   * This class provides static utility methods for input/output operations.
   * <ul>
   * <li>closeQuietly - these methods close a stream ignoring nulls and exceptions
   * <li>toXxx/read - these methods read data from a stream
   * <li>write - these methods write data to a stream
   * <li>copy - these methods copy all the data from one stream to another
   * <li>contentEquals - these methods compare the content of two streams
   * </ul>
   * <p>
   * The byte-to-char methods and char-to-byte methods involve a conversion step. Two methods are provided in each case, one that uses the
   * platform default encoding and the other which allows you to specify an encoding. You are encouraged to always specify an encoding because
   * relying on the platform default can lead to unexpected results, for example when moving from development to production.
   * <p>
   * All the methods in this class that read a stream are buffered internally. This means that there is no cause to use a
   * <code>BufferedInputStream</code> or <code>BufferedReader</code>. The default buffer size of 4K has been shown to be efficient in tests.
   * <p>
   * The various copy methods all delegate the actual copying to one of the following methods:
   * <ul>
   * <li>{@link #copyLarge(InputStream, OutputStream, byte[])}</li>
   * <li>{@link #copyLarge(InputStream, OutputStream, long, long, byte[])}</li>
   * <li>{@link #copyLarge(Reader, Writer, char[])}</li>
   * <li>{@link #copyLarge(Reader, Writer, long, long, char[])}</li>
   * </ul>
   * For example, {@link #copy(InputStream, OutputStream)} calls {@link #copyLarge(InputStream, OutputStream)} which calls {@link
   * #copy(InputStream, OutputStream, int)} which creates the buffer and calls {@link #copyLarge(InputStream, OutputStream, byte[])}.
   * <p>
   * Applications can re-use buffers by using the underlying methods directly. This may improve performance for applications that need to do a
   * lot of copying.
   * <p>
   * Wherever possible, the methods in this class do <em>not</em> flush or close the stream. This is to avoid making non-portable assumptions
   * about the streams' origin and further use. Thus the caller is still responsible for closing streams after use.
   * <p>
   * Origin of code: Excalibur.
   *
   * @version $Id: IOUtils.java 1722156 2015-12-29 15:40:07Z ggregory $
   */
  public class IOUtils {
      // NOTE: This class is focused on InputStream, OutputStream, Reader and
      // Writer. Each method should take at least one of these as a parameter,
      // or return one of them.
  
      /**
       * Represents the end-of-file (or stream).
       *
       * @since 2.5 (made public)
       */
      public static final int EOF = -1;
  
      /**
       * The Unix directory separator character.
       */
      public static final char   DIR_SEPARATOR_UNIX     = '/';
      /**
       * The Windows directory separator character.
       */
      public static final char   DIR_SEPARATOR_WINDOWS  = '\\';
      /**
       * The system directory separator character.
       */
      public static final char   DIR_SEPARATOR          = File.separatorChar;
      /**
       * The Unix line separator string.
       */
      public static final String LINE_SEPARATOR_UNIX    = "\n";
      /**
       * The Windows line separator string.
       */
      public static final String LINE_SEPARATOR_WINDOWS = "\r\n";
      /**
       * The system line separator string.
       */
      public static final String LINE_SEPARATOR;
  
      static {
          // avoid security issues
          final StringBuilderWriter buf = new StringBuilderWriter(4);
          final PrintWriter out = new PrintWriter(buf);
          out.println();
          LINE_SEPARATOR = buf.toString();
          out.close();
      }
  
      /**
       * The default buffer size ({@value}) to use for {@link #copyLarge(InputStream, OutputStream)} and {@link #copyLarge(Reader, Writer)}
       */
      private static final int DEFAULT_BUFFER_SIZE = 1024 * 4;
  
      /**
       * The default buffer size to use for the skip() methods.
       */
      private static final int SKIP_BUFFER_SIZE = 2048;
  
      // Allocated in the relevant skip method if necessary.
      /*
       * These buffers are static and are shared between threads.
       * This is possible because the buffers are write-only - the contents are never read.
       *
       * N.B. there is no need to synchronize when creating these because:
       * - we don't care if the buffer is created multiple times (the data is ignored)
       * - we always use the same size buffer, so if it it is recreated it will still be OK
       * (if the buffer size were variable, we would need to synch. to ensure some other thread
       * did not create a smaller one)
       */
      private static char[] SKIP_CHAR_BUFFER;
      private static byte[] SKIP_BYTE_BUFFER;
  
      /**
       * Instances should NOT be constructed in standard programming.
       */
      public IOUtils() {
          super();
      }
  
      //-----------------------------------------------------------------------
  
      /**
       * Closes a URLConnection.
       *
       * @param conn the connection to close.
       * @since 2.4
       */
      public static void close(final URLConnection conn) {
          if (conn instanceof HttpURLConnection) {
              ((HttpURLConnection) conn).disconnect();
          }
      }
  
      /**
       * Closes an <code>Reader</code> unconditionally.
       * <p>
       * Equivalent to {@link Reader#close()}, except any exceptions will be ignored. This is typically used in finally blocks.
       * <p>
       * Example code:
       * <pre>
       *   char[] data = new char[1024];
       *   Reader in = null;
       *   try {
       *       in = new FileReader("foo.txt");
       *       in.read(data);
       *       in.close(); //close errors are handled
       *   } catch (Exception e) {
       *       // error handling
       *   } finally {
       *       IOUtils.closeQuietly(in);
       *   }
       * </pre>
       *
       * @param input the Reader to close, may be null or already closed
       */
      public static void closeQuietly(final Reader input) {
          closeQuietly((Closeable) input);
      }
  
      /**
       * Closes an <code>Writer</code> unconditionally.
       * <p>
       * Equivalent to {@link Writer#close()}, except any exceptions will be ignored. This is typically used in finally blocks.
       * <p>
       * Example code:
       * <pre>
       *   Writer out = null;
       *   try {
       *       out = new StringWriter();
       *       out.write("Hello World");
       *       out.close(); //close errors are handled
       *   } catch (Exception e) {
       *       // error handling
       *   } finally {
       *       IOUtils.closeQuietly(out);
       *   }
       * </pre>
       *
       * @param output the Writer to close, may be null or already closed
       */
      public static void closeQuietly(final Writer output) {
          closeQuietly((Closeable) output);
      }
  
      /**
       * Closes an <code>InputStream</code> unconditionally.
       * <p>
       * Equivalent to {@link InputStream#close()}, except any exceptions will be ignored. This is typically used in finally blocks.
       * <p>
       * Example code:
       * <pre>
       *   byte[] data = new byte[1024];
       *   InputStream in = null;
       *   try {
       *       in = new FileInputStream("foo.txt");
       *       in.read(data);
       *       in.close(); //close errors are handled
       *   } catch (Exception e) {
       *       // error handling
       *   } finally {
       *       IOUtils.closeQuietly(in);
       *   }
       * </pre>
       *
       * @param input the InputStream to close, may be null or already closed
       */
      public static void closeQuietly(final InputStream input) {
          closeQuietly((Closeable) input);
      }
  
      /**
       * Closes an <code>OutputStream</code> unconditionally.
       * <p>
       * Equivalent to {@link OutputStream#close()}, except any exceptions will be ignored. This is typically used in finally blocks.
       * <p>
       * Example code:
       * <pre>
       * byte[] data = "Hello, World".getBytes();
       *
       * OutputStream out = null;
       * try {
       *     out = new FileOutputStream("foo.txt");
       *     out.write(data);
       *     out.close(); //close errors are handled
       * } catch (IOException e) {
       *     // error handling
       * } finally {
       *     IOUtils.closeQuietly(out);
       * }
       * </pre>
       *
       * @param output the OutputStream to close, may be null or already closed
       */
      public static void closeQuietly(final OutputStream output) {
          closeQuietly((Closeable) output);
      }
  
      /**
       * Closes a <code>Closeable</code> unconditionally.
       * <p>
       * Equivalent to {@link Closeable#close()}, except any exceptions will be ignored. This is typically used in finally blocks.
       * <p>
       * Example code:
       * </p>
       * <pre>
       * Closeable closeable = null;
       * try {
       *     closeable = new FileReader(&quot;foo.txt&quot;);
       *     // process closeable
       *     closeable.close();
       * } catch (Exception e) {
       *     // error handling
       * } finally {
       *     IOUtils.closeQuietly(closeable);
       * }
       * </pre>
       * <p>
       * Closing all streams:
       * </p>
       * <pre>
       * try {
       *     return IOUtils.copy(inputStream, outputStream);
       * } finally {
       *     IOUtils.closeQuietly(inputStream);
       *     IOUtils.closeQuietly(outputStream);
       * }
       * </pre>
       *
       * @param closeable the objects to close, may be null or already closed
       * @since 2.0
       */
      public static void closeQuietly(final Closeable closeable) {
          try {
              if (closeable != null) {
                  closeable.close();
              }
          } catch (final IOException ioe) {
              // ignore
          }
      }
  
      /**
       * Closes a <code>Closeable</code> unconditionally.
       * <p>
       * Equivalent to {@link Closeable#close()}, except any exceptions will be ignored.
       * <p>
       * This is typically used in finally blocks to ensure that the closeable is closed even if an Exception was thrown before the normal
       * close statement was reached.
       * <br>
       * <b>It should not be used to replace the close statement(s)
       * which should be present for the non-exceptional case.</b>
       * <br>
       * It is only intended to simplify tidying up where normal processing has already failed and reporting close failure as well is not
       * necessary or useful.
       * <p>
       * Example code:
       * </p>
       * <pre>
       * Closeable closeable = null;
       * try {
       *     closeable = new FileReader(&quot;foo.txt&quot;);
       *     // processing using the closeable; may throw an Exception
       *     closeable.close(); // Normal close - exceptions not ignored
       * } catch (Exception e) {
       *     // error handling
       * } finally {
       *     <b>IOUtils.closeQuietly(closeable); // In case normal close was skipped due to Exception</b>
       * }
       * </pre>
       * <p>
       * Closing all streams:
       * <br>
       * <pre>
       * try {
       *     return IOUtils.copy(inputStream, outputStream);
       * } finally {
       *     IOUtils.closeQuietly(inputStream, outputStream);
       * }
       * </pre>
       *
       * @param closeables the objects to close, may be null or already closed
       * @see #closeQuietly(Closeable)
       * @since 2.5
       */
      public static void closeQuietly(final Closeable... closeables) {
          if (closeables == null) {
              return;
          }
          for (final Closeable closeable : closeables) {
              closeQuietly(closeable);
          }
      }
  
      /**
       * Closes a <code>Socket</code> unconditionally.
       * <p>
       * Equivalent to {@link Socket#close()}, except any exceptions will be ignored. This is typically used in finally blocks.
       * <p>
       * Example code:
       * <pre>
       *   Socket socket = null;
       *   try {
       *       socket = new Socket("http://www.foo.com/", 80);
       *       // process socket
       *       socket.close();
       *   } catch (Exception e) {
       *       // error handling
       *   } finally {
       *       IOUtils.closeQuietly(socket);
       *   }
       * </pre>
       *
       * @param sock the Socket to close, may be null or already closed
       * @since 2.0
       */
      public static void closeQuietly(final Socket sock) {
          if (sock != null) {
              try {
                  sock.close();
              } catch (final IOException ioe) {
                  // ignored
              }
          }
      }
  
      /**
       * Closes a <code>Selector</code> unconditionally.
       * <p>
       * Equivalent to {@link Selector#close()}, except any exceptions will be ignored. This is typically used in finally blocks.
       * <p>
       * Example code:
       * <pre>
       *   Selector selector = null;
       *   try {
       *       selector = Selector.open();
       *       // process socket
       *
       *   } catch (Exception e) {
       *       // error handling
       *   } finally {
       *       IOUtils.closeQuietly(selector);
       *   }
       * </pre>
       *
       * @param selector the Selector to close, may be null or already closed
       * @since 2.2
       */
      public static void closeQuietly(final Selector selector) {
          if (selector != null) {
              try {
                  selector.close();
              } catch (final IOException ioe) {
                  // ignored
              }
          }
      }
  
      /**
       * Closes a <code>ServerSocket</code> unconditionally.
       * <p>
       * Equivalent to {@link ServerSocket#close()}, except any exceptions will be ignored. This is typically used in finally blocks.
       * <p>
       * Example code:
       * <pre>
       *   ServerSocket socket = null;
       *   try {
       *       socket = new ServerSocket();
       *       // process socket
       *       socket.close();
       *   } catch (Exception e) {
       *       // error handling
       *   } finally {
       *       IOUtils.closeQuietly(socket);
       *   }
       * </pre>
       *
       * @param sock the ServerSocket to close, may be null or already closed
       * @since 2.2
       */
      public static void closeQuietly(final ServerSocket sock) {
          if (sock != null) {
              try {
                  sock.close();
              } catch (final IOException ioe) {
                  // ignored
              }
          }
      }
  
      /**
       * Fetches entire contents of an <code>InputStream</code> and represent same data as result InputStream.
       * <p>
       * This method is useful where,
       * <ul>
       * <li>Source InputStream is slow.</li>
       * <li>It has network resources associated, so we cannot keep it open for
       * long time.</li>
       * <li>It has network timeout associated.</li>
       * </ul>
       * It can be used in favor of {@link #toByteArray(InputStream)}, since it avoids unnecessary allocation and copy of byte[].<br> This
       * method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       *
       * @param input Stream to be fully buffered.
       * @return A fully buffered stream.
       * @throws IOException if an I/O error occurs
       * @since 2.0
       */
      public static InputStream toBufferedInputStream(final InputStream input) throws IOException {
          return ByteArrayOutputStream.toBufferedInputStream(input);
      }
  
      /**
       * Fetches entire contents of an <code>InputStream</code> and represent same data as result InputStream.
       * <p>
       * This method is useful where,
       * <ul>
       * <li>Source InputStream is slow.</li>
       * <li>It has network resources associated, so we cannot keep it open for
       * long time.</li>
       * <li>It has network timeout associated.</li>
       * </ul>
       * It can be used in favor of {@link #toByteArray(InputStream)}, since it avoids unnecessary allocation and copy of byte[].<br> This
       * method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       *
       * @param input Stream to be fully buffered.
       * @param size  the initial buffer size
       * @return A fully buffered stream.
       * @throws IOException if an I/O error occurs
       * @since 2.5
       */
      public static InputStream toBufferedInputStream(final InputStream input, int size) throws IOException {
          return ByteArrayOutputStream.toBufferedInputStream(input, size);
      }
  
      /**
       * Returns the given reader if it is a {@link BufferedReader}, otherwise creates a BufferedReader from the given reader.
       *
       * @param reader the reader to wrap or return (not null)
       * @return the given reader or a new {@link BufferedReader} for the given reader
       * @throws NullPointerException if the input parameter is null
       * @see #buffer(Reader)
       * @since 2.2
       */
      public static BufferedReader toBufferedReader(final Reader reader) {
          return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(reader);
      }
  
      /**
       * Returns the given reader if it is a {@link BufferedReader}, otherwise creates a BufferedReader from the given reader.
       *
       * @param reader the reader to wrap or return (not null)
       * @param size   the buffer size, if a new BufferedReader is created.
       * @return the given reader or a new {@link BufferedReader} for the given reader
       * @throws NullPointerException if the input parameter is null
       * @see #buffer(Reader)
       * @since 2.5
       */
      public static BufferedReader toBufferedReader(final Reader reader, int size) {
          return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(reader, size);
      }
  
      /**
       * Returns the given reader if it is already a {@link BufferedReader}, otherwise creates a BufferedReader from the given reader.
       *
       * @param reader the reader to wrap or return (not null)
       * @return the given reader or a new {@link BufferedReader} for the given reader
       * @throws NullPointerException if the input parameter is null
       * @since 2.5
       */
      public static BufferedReader buffer(final Reader reader) {
          return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(reader);
      }
  
      /**
       * Returns the given reader if it is already a {@link BufferedReader}, otherwise creates a BufferedReader from the given reader.
       *
       * @param reader the reader to wrap or return (not null)
       * @param size   the buffer size, if a new BufferedReader is created.
       * @return the given reader or a new {@link BufferedReader} for the given reader
       * @throws NullPointerException if the input parameter is null
       * @since 2.5
       */
      public static BufferedReader buffer(final Reader reader, int size) {
          return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(reader, size);
      }
  
      /**
       * Returns the given Writer if it is already a {@link BufferedWriter}, otherwise creates a BufferedWriter from the given Writer.
       *
       * @param writer the Writer to wrap or return (not null)
       * @return the given Writer or a new {@link BufferedWriter} for the given Writer
       * @throws NullPointerException if the input parameter is null
       * @since 2.5
       */
      public static BufferedWriter buffer(final Writer writer) {
          return writer instanceof BufferedWriter ? (BufferedWriter) writer : new BufferedWriter(writer);
      }
  
      /**
       * Returns the given Writer if it is already a {@link BufferedWriter}, otherwise creates a BufferedWriter from the given Writer.
       *
       * @param writer the Writer to wrap or return (not null)
       * @param size   the buffer size, if a new BufferedWriter is created.
       * @return the given Writer or a new {@link BufferedWriter} for the given Writer
       * @throws NullPointerException if the input parameter is null
       * @since 2.5
       */
      public static BufferedWriter buffer(final Writer writer, int size) {
          return writer instanceof BufferedWriter ? (BufferedWriter) writer : new BufferedWriter(writer, size);
      }
  
      /**
       * Returns the given OutputStream if it is already a {@link BufferedOutputStream}, otherwise creates a BufferedOutputStream from the
       * given OutputStream.
       *
       * @param outputStream the OutputStream to wrap or return (not null)
       * @return the given OutputStream or a new {@link BufferedOutputStream} for the given OutputStream
       * @throws NullPointerException if the input parameter is null
       * @since 2.5
       */
      public static BufferedOutputStream buffer(final OutputStream outputStream) {
          // reject null early on rather than waiting for IO operation to fail
          if (outputStream == null) { // not checked by BufferedOutputStream
              throw new NullPointerException();
          }
          return outputStream instanceof BufferedOutputStream ?
                  (BufferedOutputStream) outputStream : new BufferedOutputStream(outputStream);
      }
  
      /**
       * Returns the given OutputStream if it is already a {@link BufferedOutputStream}, otherwise creates a BufferedOutputStream from the
       * given OutputStream.
       *
       * @param outputStream the OutputStream to wrap or return (not null)
       * @param size         the buffer size, if a new BufferedOutputStream is created.
       * @return the given OutputStream or a new {@link BufferedOutputStream} for the given OutputStream
       * @throws NullPointerException if the input parameter is null
       * @since 2.5
       */
      public static BufferedOutputStream buffer(final OutputStream outputStream, int size) {
          // reject null early on rather than waiting for IO operation to fail
          if (outputStream == null) { // not checked by BufferedOutputStream
              throw new NullPointerException();
          }
          return outputStream instanceof BufferedOutputStream ?
                  (BufferedOutputStream) outputStream : new BufferedOutputStream(outputStream, size);
      }
  
      /**
       * Returns the given InputStream if it is already a {@link BufferedInputStream}, otherwise creates a BufferedInputStream from the given
       * InputStream.
       *
       * @param inputStream the InputStream to wrap or return (not null)
       * @return the given InputStream or a new {@link BufferedInputStream} for the given InputStream
       * @throws NullPointerException if the input parameter is null
       * @since 2.5
       */
      public static BufferedInputStream buffer(final InputStream inputStream) {
          // reject null early on rather than waiting for IO operation to fail
          if (inputStream == null) { // not checked by BufferedInputStream
              throw new NullPointerException();
          }
          return inputStream instanceof BufferedInputStream ?
                  (BufferedInputStream) inputStream : new BufferedInputStream(inputStream);
      }
  
      /**
       * Returns the given InputStream if it is already a {@link BufferedInputStream}, otherwise creates a BufferedInputStream from the given
       * InputStream.
       *
       * @param inputStream the InputStream to wrap or return (not null)
       * @param size        the buffer size, if a new BufferedInputStream is created.
       * @return the given InputStream or a new {@link BufferedInputStream} for the given InputStream
       * @throws NullPointerException if the input parameter is null
       * @since 2.5
       */
      public static BufferedInputStream buffer(final InputStream inputStream, int size) {
          // reject null early on rather than waiting for IO operation to fail
          if (inputStream == null) { // not checked by BufferedInputStream
              throw new NullPointerException();
          }
          return inputStream instanceof BufferedInputStream ?
                  (BufferedInputStream) inputStream : new BufferedInputStream(inputStream, size);
      }
  
      // read toByteArray
      //-----------------------------------------------------------------------
  
      /**
       * Gets the contents of an <code>InputStream</code> as a <code>byte[]</code>.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       *
       * @param input the <code>InputStream</code> to read from
       * @return the requested byte array
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       */
      public static byte[] toByteArray(final InputStream input) throws IOException {
          final ByteArrayOutputStream output = new ByteArrayOutputStream();
          copy(input, output);
          return output.toByteArray();
      }
  
      /**
       * Gets contents of an <code>InputStream</code> as a <code>byte[]</code>. Use this method instead of
       * <code>toByteArray(InputStream)</code> when <code>InputStream</code> size is known.
       * <b>NOTE:</b> the method checks that the length can safely be cast to an int without truncation
       * before using {@link IOUtils#toByteArray(InputStream, int)} to read into the byte array. (Arrays can have no more than
       * Integer.MAX_VALUE entries anyway)
       *
       * @param input the <code>InputStream</code> to read from
       * @param size  the size of <code>InputStream</code>
       * @return the requested byte array
       * @throws IOException              if an I/O error occurs or <code>InputStream</code> size differ from parameter size
       * @throws IllegalArgumentException if size is less than zero or size is greater than Integer.MAX_VALUE
       * @see IOUtils#toByteArray(InputStream, int)
       * @since 2.1
       */
      public static byte[] toByteArray(final InputStream input, final long size) throws IOException {
  
          if (size > Integer.MAX_VALUE) {
              throw new IllegalArgumentException("Size cannot be greater than Integer max value: " + size);
          }
  
          return toByteArray(input, (int) size);
      }
  
      /**
       * Gets the contents of an <code>InputStream</code> as a <code>byte[]</code>. Use this method instead of
       * <code>toByteArray(InputStream)</code> when <code>InputStream</code> size is known
       *
       * @param input the <code>InputStream</code> to read from
       * @param size  the size of <code>InputStream</code>
       * @return the requested byte array
       * @throws IOException              if an I/O error occurs or <code>InputStream</code> size differ from parameter size
       * @throws IllegalArgumentException if size is less than zero
       * @since 2.1
       */
      public static byte[] toByteArray(final InputStream input, final int size) throws IOException {
  
          if (size < 0) {
              throw new IllegalArgumentException("Size must be equal or greater than zero: " + size);
          }
  
          if (size == 0) {
              return new byte[0];
          }
  
          final byte[] data = new byte[size];
          int offset = 0;
          int readed;
  
          while (offset < size && (readed = input.read(data, offset, size - offset)) != EOF) {
              offset += readed;
          }
  
          if (offset != size) {
              throw new IOException("Unexpected readed size. current: " + offset + ", excepted: " + size);
          }
  
          return data;
      }
  
      /**
       * Gets the contents of a <code>Reader</code> as a <code>byte[]</code> using the default character encoding of the platform.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       *
       * @param input the <code>Reader</code> to read from
       * @return the requested byte array
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       * @deprecated 2.5 use {@link #toByteArray(Reader, Charset)} instead
       */
      @Deprecated
      public static byte[] toByteArray(final Reader input) throws IOException {
          return toByteArray(input, Charset.defaultCharset());
      }
  
      /**
       * Gets the contents of a <code>Reader</code> as a <code>byte[]</code> using the specified character encoding.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       *
       * @param input    the <code>Reader</code> to read from
       * @param encoding the encoding to use, null means platform default
       * @return the requested byte array
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       * @since 2.3
       */
      public static byte[] toByteArray(final Reader input, final Charset encoding) throws IOException {
          final ByteArrayOutputStream output = new ByteArrayOutputStream();
          copy(input, output, encoding);
          return output.toByteArray();
      }
  
      /**
       * Gets the contents of a <code>Reader</code> as a <code>byte[]</code> using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       *
       * @param input    the <code>Reader</code> to read from
       * @param encoding the encoding to use, null means platform default
       * @return the requested byte array
       * @throws NullPointerException                         if the input is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 1.1
       */
      public static byte[] toByteArray(final Reader input, final String encoding) throws IOException {
          return toByteArray(input, Charsets.toCharset(encoding));
      }
  
      /**
       * Gets the contents of a <code>String</code> as a <code>byte[]</code> using the default character encoding of the platform.
       * <p>
       * This is the same as {@link String#getBytes()}.
       *
       * @param input the <code>String</code> to convert
       * @return the requested byte array
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs (never occurs)
       * @deprecated 2.5 Use {@link String#getBytes()} instead
       */
      @Deprecated
      public static byte[] toByteArray(final String input) throws IOException {
          // make explicit the use of the default charset
          return input.getBytes(Charset.defaultCharset());
      }
  
      /**
       * Gets the contents of a <code>URI</code> as a <code>byte[]</code>.
       *
       * @param uri the <code>URI</code> to read
       * @return the requested byte array
       * @throws NullPointerException if the uri is null
       * @throws IOException          if an I/O exception occurs
       * @since 2.4
       */
      public static byte[] toByteArray(final URI uri) throws IOException {
          return IOUtils.toByteArray(uri.toURL());
      }
  
      /**
       * Gets the contents of a <code>URL</code> as a <code>byte[]</code>.
       *
       * @param url the <code>URL</code> to read
       * @return the requested byte array
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O exception occurs
       * @since 2.4
       */
      public static byte[] toByteArray(final URL url) throws IOException {
          final URLConnection conn = url.openConnection();
          try {
              return IOUtils.toByteArray(conn);
          } finally {
              close(conn);
          }
      }
  
      /**
       * Gets the contents of a <code>URLConnection</code> as a <code>byte[]</code>.
       *
       * @param urlConn the <code>URLConnection</code> to read
       * @return the requested byte array
       * @throws NullPointerException if the urlConn is null
       * @throws IOException          if an I/O exception occurs
       * @since 2.4
       */
      public static byte[] toByteArray(final URLConnection urlConn) throws IOException {
          final InputStream inputStream = urlConn.getInputStream();
          try {
              return IOUtils.toByteArray(inputStream);
          } finally {
              inputStream.close();
          }
      }
  
      // read char[]
      //-----------------------------------------------------------------------
  
      /**
       * Gets the contents of an <code>InputStream</code> as a character array using the default character encoding of the platform.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       *
       * @param is the <code>InputStream</code> to read from
       * @return the requested character array
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       * @deprecated 2.5 use {@link #toCharArray(InputStream, Charset)} instead
       */
      @Deprecated
      public static char[] toCharArray(final InputStream is) throws IOException {
          return toCharArray(is, Charset.defaultCharset());
      }
  
      /**
       * Gets the contents of an <code>InputStream</code> as a character array using the specified character encoding.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       *
       * @param is       the <code>InputStream</code> to read from
       * @param encoding the encoding to use, null means platform default
       * @return the requested character array
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       * @since 2.3
       */
      public static char[] toCharArray(final InputStream is, final Charset encoding)
              throws IOException {
          final CharArrayWriter output = new CharArrayWriter();
          copy(is, output, encoding);
          return output.toCharArray();
      }
  
      /**
       * Gets the contents of an <code>InputStream</code> as a character array using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       *
       * @param is       the <code>InputStream</code> to read from
       * @param encoding the encoding to use, null means platform default
       * @return the requested character array
       * @throws NullPointerException                         if the input is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 1.1
       */
      public static char[] toCharArray(final InputStream is, final String encoding) throws IOException {
          return toCharArray(is, Charsets.toCharset(encoding));
      }
  
      /**
       * Gets the contents of a <code>Reader</code> as a character array.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       *
       * @param input the <code>Reader</code> to read from
       * @return the requested character array
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       */
      public static char[] toCharArray(final Reader input) throws IOException {
          final CharArrayWriter sw = new CharArrayWriter();
          copy(input, sw);
          return sw.toCharArray();
      }
  
      // read toString
      //-----------------------------------------------------------------------
  
      /**
       * Gets the contents of an <code>InputStream</code> as a String using the default character encoding of the platform.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       *
       * @param input the <code>InputStream</code> to read from
       * @return the requested String
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       * @deprecated 2.5 use {@link #toString(InputStream, Charset)} instead
       */
      @Deprecated
      public static String toString(final InputStream input) throws IOException {
          return toString(input, Charset.defaultCharset());
      }
  
      /**
       * Gets the contents of an <code>InputStream</code> as a String using the specified character encoding.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       * </p>
       *
       * @param input    the <code>InputStream</code> to read from
       * @param encoding the encoding to use, null means platform default
       * @return the requested String
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       * @since 2.3
       */
      public static String toString(final InputStream input, final Charset encoding) throws IOException {
          final StringBuilderWriter sw = new StringBuilderWriter();
          copy(input, sw, encoding);
          return sw.toString();
      }
  
      /**
       * Gets the contents of an <code>InputStream</code> as a String using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       *
       * @param input    the <code>InputStream</code> to read from
       * @param encoding the encoding to use, null means platform default
       * @return the requested String
       * @throws NullPointerException                         if the input is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       */
      public static String toString(final InputStream input, final String encoding)
              throws IOException {
          return toString(input, Charsets.toCharset(encoding));
      }
  
      /**
       * Gets the contents of a <code>Reader</code> as a String.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       *
       * @param input the <code>Reader</code> to read from
       * @return the requested String
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       */
      public static String toString(final Reader input) throws IOException {
          final StringBuilderWriter sw = new StringBuilderWriter();
          copy(input, sw);
          return sw.toString();
      }
  
      /**
       * Gets the contents at the given URI.
       *
       * @param uri The URI source.
       * @return The contents of the URL as a String.
       * @throws IOException if an I/O exception occurs.
       * @since 2.1
       * @deprecated 2.5 use {@link #toString(URI, Charset)} instead
       */
      @Deprecated
      public static String toString(final URI uri) throws IOException {
          return toString(uri, Charset.defaultCharset());
      }
  
      /**
       * Gets the contents at the given URI.
       *
       * @param uri      The URI source.
       * @param encoding The encoding name for the URL contents.
       * @return The contents of the URL as a String.
       * @throws IOException if an I/O exception occurs.
       * @since 2.3.
       */
      public static String toString(final URI uri, final Charset encoding) throws IOException {
          return toString(uri.toURL(), Charsets.toCharset(encoding));
      }
  
      /**
       * Gets the contents at the given URI.
       *
       * @param uri      The URI source.
       * @param encoding The encoding name for the URL contents.
       * @return The contents of the URL as a String.
       * @throws IOException                                  if an I/O exception occurs.
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 2.1
       */
      public static String toString(final URI uri, final String encoding) throws IOException {
          return toString(uri, Charsets.toCharset(encoding));
      }
  
      /**
       * Gets the contents at the given URL.
       *
       * @param url The URL source.
       * @return The contents of the URL as a String.
       * @throws IOException if an I/O exception occurs.
       * @since 2.1
       * @deprecated 2.5 use {@link #toString(URL, Charset)} instead
       */
      @Deprecated
      public static String toString(final URL url) throws IOException {
          return toString(url, Charset.defaultCharset());
      }
  
      /**
       * Gets the contents at the given URL.
       *
       * @param url      The URL source.
       * @param encoding The encoding name for the URL contents.
       * @return The contents of the URL as a String.
       * @throws IOException if an I/O exception occurs.
       * @since 2.3
       */
      public static String toString(final URL url, final Charset encoding) throws IOException {
          final InputStream inputStream = url.openStream();
          try {
              return toString(inputStream, encoding);
          } finally {
              inputStream.close();
          }
      }
  
      /**
       * Gets the contents at the given URL.
       *
       * @param url      The URL source.
       * @param encoding The encoding name for the URL contents.
       * @return The contents of the URL as a String.
       * @throws IOException                                  if an I/O exception occurs.
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 2.1
       */
      public static String toString(final URL url, final String encoding) throws IOException {
          return toString(url, Charsets.toCharset(encoding));
      }
  
      /**
       * Gets the contents of a <code>byte[]</code> as a String using the default character encoding of the platform.
       *
       * @param input the byte array to read from
       * @return the requested String
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs (never occurs)
       * @deprecated 2.5 Use {@link String#String(byte[])} instead
       */
      @Deprecated
      public static String toString(final byte[] input) throws IOException {
          // make explicit the use of the default charset
          return new String(input, Charset.defaultCharset());
      }
  
      /**
       * Gets the contents of a <code>byte[]</code> as a String using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       *
       * @param input    the byte array to read from
       * @param encoding the encoding to use, null means platform default
       * @return the requested String
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs (never occurs)
       */
      public static String toString(final byte[] input, final String encoding) throws IOException {
          return new String(input, Charsets.toCharset(encoding));
      }
  
      // readLines
      //-----------------------------------------------------------------------
  
      /**
       * Gets the contents of an <code>InputStream</code> as a list of Strings, one entry per line, using the default character encoding of
       * the platform.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       *
       * @param input the <code>InputStream</code> to read from, not null
       * @return the list of Strings, never null
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       * @deprecated 2.5 use {@link #readLines(InputStream, Charset)} instead
       */
      @Deprecated
      public static List<String> readLines(final InputStream input) throws IOException {
          return readLines(input, Charset.defaultCharset());
      }
  
      /**
       * Gets the contents of an <code>InputStream</code> as a list of Strings, one entry per line, using the specified character encoding.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       *
       * @param input    the <code>InputStream</code> to read from, not null
       * @param encoding the encoding to use, null means platform default
       * @return the list of Strings, never null
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       * @since 2.3
       */
      public static List<String> readLines(final InputStream input, final Charset encoding) throws IOException {
          final InputStreamReader reader = new InputStreamReader(input, Charsets.toCharset(encoding));
          return readLines(reader);
      }
  
      /**
       * Gets the contents of an <code>InputStream</code> as a list of Strings, one entry per line, using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       *
       * @param input    the <code>InputStream</code> to read from, not null
       * @param encoding the encoding to use, null means platform default
       * @return the list of Strings, never null
       * @throws NullPointerException                         if the input is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 1.1
       */
      public static List<String> readLines(final InputStream input, final String encoding) throws IOException {
          return readLines(input, Charsets.toCharset(encoding));
      }
  
      /**
       * Gets the contents of a <code>Reader</code> as a list of Strings, one entry per line.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       *
       * @param input the <code>Reader</code> to read from, not null
       * @return the list of Strings, never null
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       */
      public static List<String> readLines(final Reader input) throws IOException {
          final BufferedReader reader = toBufferedReader(input);
          final List<String> list = new ArrayList<String>();
          String line = reader.readLine();
          while (line != null) {
              list.add(line);
              line = reader.readLine();
          }
          return list;
      }
  
      /**
       * Converts the specified CharSequence to an input stream, encoded as bytes using the default character encoding of the platform.
       *
       * @param input the CharSequence to convert
       * @return an input stream
       * @since 2.0
       * @deprecated 2.5 use {@link #toInputStream(CharSequence, Charset)} instead
       */
      @Deprecated
      public static InputStream toInputStream(final CharSequence input) {
          return toInputStream(input, Charset.defaultCharset());
      }
  
      /**
       * Converts the specified CharSequence to an input stream, encoded as bytes using the specified character encoding.
       *
       * @param input    the CharSequence to convert
       * @param encoding the encoding to use, null means platform default
       * @return an input stream
       * @since 2.3
       */
      public static InputStream toInputStream(final CharSequence input, final Charset encoding) {
          return toInputStream(input.toString(), encoding);
      }
  
      /**
       * Converts the specified CharSequence to an input stream, encoded as bytes using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       *
       * @param input    the CharSequence to convert
       * @param encoding the encoding to use, null means platform default
       * @return an input stream
       * @throws IOException                                  if the encoding is invalid
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 2.0
       */
      public static InputStream toInputStream(final CharSequence input, final String encoding) throws IOException {
          return toInputStream(input, Charsets.toCharset(encoding));
      }
  
      //-----------------------------------------------------------------------
  
      /**
       * Converts the specified string to an input stream, encoded as bytes using the default character encoding of the platform.
       *
       * @param input the string to convert
       * @return an input stream
       * @since 1.1
       * @deprecated 2.5 use {@link #toInputStream(String, Charset)} instead
       */
      @Deprecated
      public static InputStream toInputStream(final String input) {
          return toInputStream(input, Charset.defaultCharset());
      }
  
      /**
       * Converts the specified string to an input stream, encoded as bytes using the specified character encoding.
       *
       * @param input    the string to convert
       * @param encoding the encoding to use, null means platform default
       * @return an input stream
       * @since 2.3
       */
      public static InputStream toInputStream(final String input, final Charset encoding) {
          return new ByteArrayInputStream(input.getBytes(Charsets.toCharset(encoding)));
      }
  
      /**
       * Converts the specified string to an input stream, encoded as bytes using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       *
       * @param input    the string to convert
       * @param encoding the encoding to use, null means platform default
       * @return an input stream
       * @throws IOException                                  if the encoding is invalid
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 1.1
       */
      public static InputStream toInputStream(final String input, final String encoding) throws IOException {
          final byte[] bytes = input.getBytes(Charsets.toCharset(encoding));
          return new ByteArrayInputStream(bytes);
      }
  
      // write byte[]
      //-----------------------------------------------------------------------
  
      /**
       * Writes bytes from a <code>byte[]</code> to an <code>OutputStream</code>.
       *
       * @param data   the byte array to write, do not modify during output, null ignored
       * @param output the <code>OutputStream</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       */
      public static void write(final byte[] data, final OutputStream output)
              throws IOException {
          if (data != null) {
              output.write(data);
          }
      }
  
      /**
       * Writes bytes from a <code>byte[]</code> to an <code>OutputStream</code> using chunked writes. This is intended for writing very large
       * byte arrays which might otherwise cause excessive memory usage if the native code has to allocate a copy.
       *
       * @param data   the byte array to write, do not modify during output, null ignored
       * @param output the <code>OutputStream</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.5
       */
      public static void writeChunked(final byte[] data, final OutputStream output)
              throws IOException {
          if (data != null) {
              int bytes = data.length;
              int offset = 0;
              while (bytes > 0) {
                  int chunk = Math.min(bytes, DEFAULT_BUFFER_SIZE);
                  output.write(data, offset, chunk);
                  bytes -= chunk;
                  offset += chunk;
              }
          }
      }
  
      /**
       * Writes bytes from a <code>byte[]</code> to chars on a <code>Writer</code> using the default character encoding of the platform.
       * <p>
       * This method uses {@link String#String(byte[])}.
       *
       * @param data   the byte array to write, do not modify during output, null ignored
       * @param output the <code>Writer</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       * @deprecated 2.5 use {@link #write(byte[], Writer, Charset)} instead
       */
      @Deprecated
      public static void write(final byte[] data, final Writer output) throws IOException {
          write(data, output, Charset.defaultCharset());
      }
  
      /**
       * Writes bytes from a <code>byte[]</code> to chars on a <code>Writer</code> using the specified character encoding.
       * <p>
       * This method uses {@link String#String(byte[], String)}.
       *
       * @param data     the byte array to write, do not modify during output, null ignored
       * @param output   the <code>Writer</code> to write to
       * @param encoding the encoding to use, null means platform default
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.3
       */
      public static void write(final byte[] data, final Writer output, final Charset encoding) throws IOException {
          if (data != null) {
              output.write(new String(data, Charsets.toCharset(encoding)));
          }
      }
  
      /**
       * Writes bytes from a <code>byte[]</code> to chars on a <code>Writer</code> using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       * <p>
       * This method uses {@link String#String(byte[], String)}.
       *
       * @param data     the byte array to write, do not modify during output, null ignored
       * @param output   the <code>Writer</code> to write to
       * @param encoding the encoding to use, null means platform default
       * @throws NullPointerException                         if output is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 1.1
       */
      public static void write(final byte[] data, final Writer output, final String encoding) throws IOException {
          write(data, output, Charsets.toCharset(encoding));
      }
  
      // write char[]
      //-----------------------------------------------------------------------
  
      /**
       * Writes chars from a <code>char[]</code> to a <code>Writer</code>
       *
       * @param data   the char array to write, do not modify during output, null ignored
       * @param output the <code>Writer</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       */
      public static void write(final char[] data, final Writer output) throws IOException {
          if (data != null) {
              output.write(data);
          }
      }
  
      /**
       * Writes chars from a <code>char[]</code> to a <code>Writer</code> using chunked writes. This is intended for writing very large byte
       * arrays which might otherwise cause excessive memory usage if the native code has to allocate a copy.
       *
       * @param data   the char array to write, do not modify during output, null ignored
       * @param output the <code>Writer</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.5
       */
      public static void writeChunked(final char[] data, final Writer output) throws IOException {
          if (data != null) {
              int bytes = data.length;
              int offset = 0;
              while (bytes > 0) {
                  int chunk = Math.min(bytes, DEFAULT_BUFFER_SIZE);
                  output.write(data, offset, chunk);
                  bytes -= chunk;
                  offset += chunk;
              }
          }
      }
  
      /**
       * Writes chars from a <code>char[]</code> to bytes on an
       * <code>OutputStream</code>.
       * <p>
       * This method uses {@link String#String(char[])} and {@link String#getBytes()}.
       *
       * @param data   the char array to write, do not modify during output, null ignored
       * @param output the <code>OutputStream</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       * @deprecated 2.5 use {@link #write(char[], OutputStream, Charset)} instead
       */
      @Deprecated
      public static void write(final char[] data, final OutputStream output)
              throws IOException {
          write(data, output, Charset.defaultCharset());
      }
  
      /**
       * Writes chars from a <code>char[]</code> to bytes on an
       * <code>OutputStream</code> using the specified character encoding.
       * <p>
       * This method uses {@link String#String(char[])} and {@link String#getBytes(String)}.
       *
       * @param data     the char array to write, do not modify during output, null ignored
       * @param output   the <code>OutputStream</code> to write to
       * @param encoding the encoding to use, null means platform default
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.3
       */
      public static void write(final char[] data, final OutputStream output, final Charset encoding) throws IOException {
          if (data != null) {
              output.write(new String(data).getBytes(Charsets.toCharset(encoding)));
          }
      }
  
      /**
       * Writes chars from a <code>char[]</code> to bytes on an
       * <code>OutputStream</code> using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       * <p>
       * This method uses {@link String#String(char[])} and {@link String#getBytes(String)}.
       *
       * @param data     the char array to write, do not modify during output, null ignored
       * @param output   the <code>OutputStream</code> to write to
       * @param encoding the encoding to use, null means platform default
       * @throws NullPointerException                         if output is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 1.1
       */
      public static void write(final char[] data, final OutputStream output, final String encoding)
              throws IOException {
          write(data, output, Charsets.toCharset(encoding));
      }
  
      // write CharSequence
      //-----------------------------------------------------------------------
  
      /**
       * Writes chars from a <code>CharSequence</code> to a <code>Writer</code>.
       *
       * @param data   the <code>CharSequence</code> to write, null ignored
       * @param output the <code>Writer</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.0
       */
      public static void write(final CharSequence data, final Writer output) throws IOException {
          if (data != null) {
              write(data.toString(), output);
          }
      }
  
      /**
       * Writes chars from a <code>CharSequence</code> to bytes on an
       * <code>OutputStream</code> using the default character encoding of the
       * platform.
       * <p>
       * This method uses {@link String#getBytes()}.
       *
       * @param data   the <code>CharSequence</code> to write, null ignored
       * @param output the <code>OutputStream</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.0
       * @deprecated 2.5 use {@link #write(CharSequence, OutputStream, Charset)} instead
       */
      @Deprecated
      public static void write(final CharSequence data, final OutputStream output)
              throws IOException {
          write(data, output, Charset.defaultCharset());
      }
  
      /**
       * Writes chars from a <code>CharSequence</code> to bytes on an
       * <code>OutputStream</code> using the specified character encoding.
       * <p>
       * This method uses {@link String#getBytes(String)}.
       *
       * @param data     the <code>CharSequence</code> to write, null ignored
       * @param output   the <code>OutputStream</code> to write to
       * @param encoding the encoding to use, null means platform default
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.3
       */
      public static void write(final CharSequence data, final OutputStream output, final Charset encoding)
              throws IOException {
          if (data != null) {
              write(data.toString(), output, encoding);
          }
      }
  
      /**
       * Writes chars from a <code>CharSequence</code> to bytes on an
       * <code>OutputStream</code> using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       * <p>
       * This method uses {@link String#getBytes(String)}.
       *
       * @param data     the <code>CharSequence</code> to write, null ignored
       * @param output   the <code>OutputStream</code> to write to
       * @param encoding the encoding to use, null means platform default
       * @throws NullPointerException                         if output is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 2.0
       */
      public static void write(final CharSequence data, final OutputStream output, final String encoding)
              throws IOException {
          write(data, output, Charsets.toCharset(encoding));
      }
  
      // write String
      //-----------------------------------------------------------------------
  
      /**
       * Writes chars from a <code>String</code> to a <code>Writer</code>.
       *
       * @param data   the <code>String</code> to write, null ignored
       * @param output the <code>Writer</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       */
      public static void write(final String data, final Writer output) throws IOException {
          if (data != null) {
              output.write(data);
          }
      }
  
      /**
       * Writes chars from a <code>String</code> to bytes on an
       * <code>OutputStream</code> using the default character encoding of the
       * platform.
       * <p>
       * This method uses {@link String#getBytes()}.
       *
       * @param data   the <code>String</code> to write, null ignored
       * @param output the <code>OutputStream</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       * @deprecated 2.5 use {@link #write(String, OutputStream, Charset)} instead
       */
      @Deprecated
      public static void write(final String data, final OutputStream output)
              throws IOException {
          write(data, output, Charset.defaultCharset());
      }
  
      /**
       * Writes chars from a <code>String</code> to bytes on an
       * <code>OutputStream</code> using the specified character encoding.
       * <p>
       * This method uses {@link String#getBytes(String)}.
       *
       * @param data     the <code>String</code> to write, null ignored
       * @param output   the <code>OutputStream</code> to write to
       * @param encoding the encoding to use, null means platform default
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.3
       */
      public static void write(final String data, final OutputStream output, final Charset encoding) throws IOException {
          if (data != null) {
              output.write(data.getBytes(Charsets.toCharset(encoding)));
          }
      }
  
      /**
       * Writes chars from a <code>String</code> to bytes on an
       * <code>OutputStream</code> using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       * <p>
       * This method uses {@link String#getBytes(String)}.
       *
       * @param data     the <code>String</code> to write, null ignored
       * @param output   the <code>OutputStream</code> to write to
       * @param encoding the encoding to use, null means platform default
       * @throws NullPointerException                         if output is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 1.1
       */
      public static void write(final String data, final OutputStream output, final String encoding)
              throws IOException {
          write(data, output, Charsets.toCharset(encoding));
      }
  
      // write StringBuffer
      //-----------------------------------------------------------------------
  
      /**
       * Writes chars from a <code>StringBuffer</code> to a <code>Writer</code>.
       *
       * @param data   the <code>StringBuffer</code> to write, null ignored
       * @param output the <code>Writer</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       * @deprecated replaced by write(CharSequence, Writer)
       */
      @Deprecated
      public static void write(final StringBuffer data, final Writer output)
              throws IOException {
          if (data != null) {
              output.write(data.toString());
          }
      }
  
      /**
       * Writes chars from a <code>StringBuffer</code> to bytes on an
       * <code>OutputStream</code> using the default character encoding of the
       * platform.
       * <p>
       * This method uses {@link String#getBytes()}.
       *
       * @param data   the <code>StringBuffer</code> to write, null ignored
       * @param output the <code>OutputStream</code> to write to
       * @throws NullPointerException if output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       * @deprecated replaced by write(CharSequence, OutputStream)
       */
      @Deprecated
      public static void write(final StringBuffer data, final OutputStream output)
              throws IOException {
          write(data, output, (String) null);
      }
  
      /**
       * Writes chars from a <code>StringBuffer</code> to bytes on an
       * <code>OutputStream</code> using the specified character encoding.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       * <p>
       * This method uses {@link String#getBytes(String)}.
       *
       * @param data     the <code>StringBuffer</code> to write, null ignored
       * @param output   the <code>OutputStream</code> to write to
       * @param encoding the encoding to use, null means platform default
       * @throws NullPointerException                         if output is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 1.1
       * @deprecated replaced by write(CharSequence, OutputStream, String)
       */
      @Deprecated
      public static void write(final StringBuffer data, final OutputStream output, final String encoding)
              throws IOException {
          if (data != null) {
              output.write(data.toString().getBytes(Charsets.toCharset(encoding)));
          }
      }
  
      // writeLines
      //-----------------------------------------------------------------------
  
      /**
       * Writes the <code>toString()</code> value of each item in a collection to an <code>OutputStream</code> line by line, using the default
       * character encoding of the platform and the specified line ending.
       *
       * @param lines      the lines to write, null entries produce blank lines
       * @param lineEnding the line separator to use, null is system default
       * @param output     the <code>OutputStream</code> to write to, not null, not closed
       * @throws NullPointerException if the output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       * @deprecated 2.5 use {@link #writeLines(Collection, String, OutputStream, Charset)} instead
       */
      @Deprecated
      public static void writeLines(final Collection<?> lines, final String lineEnding,
                                    final OutputStream output) throws IOException {
          writeLines(lines, lineEnding, output, Charset.defaultCharset());
      }
  
      /**
       * Writes the <code>toString()</code> value of each item in a collection to an <code>OutputStream</code> line by line, using the
       * specified character encoding and the specified line ending.
       *
       * @param lines      the lines to write, null entries produce blank lines
       * @param lineEnding the line separator to use, null is system default
       * @param output     the <code>OutputStream</code> to write to, not null, not closed
       * @param encoding   the encoding to use, null means platform default
       * @throws NullPointerException if the output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.3
       */
      public static void writeLines(final Collection<?> lines, String lineEnding, final OutputStream output,
                                    final Charset encoding) throws IOException {
          if (lines == null) {
              return;
          }
          if (lineEnding == null) {
              lineEnding = LINE_SEPARATOR;
          }
          final Charset cs = Charsets.toCharset(encoding);
          for (final Object line : lines) {
              if (line != null) {
                  output.write(line.toString().getBytes(cs));
              }
              output.write(lineEnding.getBytes(cs));
          }
      }
  
      /**
       * Writes the <code>toString()</code> value of each item in a collection to an <code>OutputStream</code> line by line, using the
       * specified character encoding and the specified line ending.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       *
       * @param lines      the lines to write, null entries produce blank lines
       * @param lineEnding the line separator to use, null is system default
       * @param output     the <code>OutputStream</code> to write to, not null, not closed
       * @param encoding   the encoding to use, null means platform default
       * @throws NullPointerException                         if the output is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 1.1
       */
      public static void writeLines(final Collection<?> lines, final String lineEnding,
                                    final OutputStream output, final String encoding) throws IOException {
          writeLines(lines, lineEnding, output, Charsets.toCharset(encoding));
      }
  
      /**
       * Writes the <code>toString()</code> value of each item in a collection to a <code>Writer</code> line by line, using the specified line
       * ending.
       *
       * @param lines      the lines to write, null entries produce blank lines
       * @param lineEnding the line separator to use, null is system default
       * @param writer     the <code>Writer</code> to write to, not null, not closed
       * @throws NullPointerException if the input is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       */
      public static void writeLines(final Collection<?> lines, String lineEnding,
                                    final Writer writer) throws IOException {
          if (lines == null) {
              return;
          }
          if (lineEnding == null) {
              lineEnding = LINE_SEPARATOR;
          }
          for (final Object line : lines) {
              if (line != null) {
                  writer.write(line.toString());
              }
              writer.write(lineEnding);
          }
      }
  
      // copy from InputStream
      //-----------------------------------------------------------------------
  
      /**
       * Copies bytes from an <code>InputStream</code> to an
       * <code>OutputStream</code>.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       * <p>
       * Large streams (over 2GB) will return a bytes copied value of
       * <code>-1</code> after the copy has completed since the correct
       * number of bytes cannot be returned as an int. For large streams use the <code>copyLarge(InputStream, OutputStream)</code> method.
       *
       * @param input  the <code>InputStream</code> to read from
       * @param output the <code>OutputStream</code> to write to
       * @return the number of bytes copied, or -1 if &gt; Integer.MAX_VALUE
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       */
      public static int copy(final InputStream input, final OutputStream output) throws IOException {
          final long count = copyLarge(input, output);
          if (count > Integer.MAX_VALUE) {
              return -1;
          }
          return (int) count;
      }
  
      /**
       * Copies bytes from an <code>InputStream</code> to an <code>OutputStream</code> using an internal buffer of the given size.
       * <p>
       * This method buffers the input internally, so there is no need to use a <code>BufferedInputStream</code>.
       * <p>
       *
       * @param input      the <code>InputStream</code> to read from
       * @param output     the <code>OutputStream</code> to write to
       * @param bufferSize the bufferSize used to copy from the input to the output
       * @return the number of bytes copied
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.5
       */
      public static long copy(final InputStream input, final OutputStream output, final int bufferSize)
              throws IOException {
          return copyLarge(input, output, new byte[bufferSize]);
      }
  
      /**
       * Copies bytes from a large (over 2GB) <code>InputStream</code> to an
       * <code>OutputStream</code>.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       * <p>
       * The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
       *
       * @param input  the <code>InputStream</code> to read from
       * @param output the <code>OutputStream</code> to write to
       * @return the number of bytes copied
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.3
       */
      public static long copyLarge(final InputStream input, final OutputStream output)
              throws IOException {
          return copy(input, output, DEFAULT_BUFFER_SIZE);
      }
  
      /**
       * Copies bytes from a large (over 2GB) <code>InputStream</code> to an
       * <code>OutputStream</code>.
       * <p>
       * This method uses the provided buffer, so there is no need to use a
       * <code>BufferedInputStream</code>.
       * <p>
       *
       * @param input  the <code>InputStream</code> to read from
       * @param output the <code>OutputStream</code> to write to
       * @param buffer the buffer to use for the copy
       * @return the number of bytes copied
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.2
       */
      public static long copyLarge(final InputStream input, final OutputStream output, final byte[] buffer)
              throws IOException {
          long count = 0;
          int n;
          while (EOF != (n = input.read(buffer))) {
              output.write(buffer, 0, n);
              count += n;
          }
          return count;
      }
  
      /**
       * Copies some or all bytes from a large (over 2GB) <code>InputStream</code> to an
       * <code>OutputStream</code>, optionally skipping input bytes.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       * </p>
       * <p>
       * Note that the implementation uses {@link #skip(InputStream, long)}. This means that the method may be considerably less efficient
       * than using the actual skip implementation, this is done to guarantee that the correct number of characters are skipped.
       * </p>
       * The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
       *
       * @param input       the <code>InputStream</code> to read from
       * @param output      the <code>OutputStream</code> to write to
       * @param inputOffset : number of bytes to skip from input before copying -ve values are ignored
       * @param length      : number of bytes to copy. -ve means all
       * @return the number of bytes copied
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.2
       */
      public static long copyLarge(final InputStream input, final OutputStream output, final long inputOffset,
                                   final long length) throws IOException {
          return copyLarge(input, output, inputOffset, length, new byte[DEFAULT_BUFFER_SIZE]);
      }
  
      /**
       * Copies some or all bytes from a large (over 2GB) <code>InputStream</code> to an
       * <code>OutputStream</code>, optionally skipping input bytes.
       * <p>
       * This method uses the provided buffer, so there is no need to use a
       * <code>BufferedInputStream</code>.
       * </p>
       * <p>
       * Note that the implementation uses {@link #skip(InputStream, long)}. This means that the method may be considerably less efficient
       * than using the actual skip implementation, this is done to guarantee that the correct number of characters are skipped.
       * </p>
       *
       * @param input       the <code>InputStream</code> to read from
       * @param output      the <code>OutputStream</code> to write to
       * @param inputOffset : number of bytes to skip from input before copying -ve values are ignored
       * @param length      : number of bytes to copy. -ve means all
       * @param buffer      the buffer to use for the copy
       * @return the number of bytes copied
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.2
       */
      public static long copyLarge(final InputStream input, final OutputStream output,
                                   final long inputOffset, final long length, final byte[] buffer) throws IOException {
          if (inputOffset > 0) {
              skipFully(input, inputOffset);
          }
          if (length == 0) {
              return 0;
          }
          final int bufferLength = buffer.length;
          int bytesToRead = bufferLength;
          if (length > 0 && length < bufferLength) {
              bytesToRead = (int) length;
          }
          int read;
          long totalRead = 0;
          while (bytesToRead > 0 && EOF != (read = input.read(buffer, 0, bytesToRead))) {
              output.write(buffer, 0, read);
              totalRead += read;
              if (length > 0) { // only adjust length if not reading to the end
                  // Note the cast must work because buffer.length is an integer
                  bytesToRead = (int) Math.min(length - totalRead, bufferLength);
              }
          }
          return totalRead;
      }
  
      /**
       * Copies bytes from an <code>InputStream</code> to chars on a
       * <code>Writer</code> using the default character encoding of the platform.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       * <p>
       * This method uses {@link InputStreamReader}.
       *
       * @param input  the <code>InputStream</code> to read from
       * @param output the <code>Writer</code> to write to
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       * @deprecated 2.5 use {@link #copy(InputStream, Writer, Charset)} instead
       */
      @Deprecated
      public static void copy(final InputStream input, final Writer output)
              throws IOException {
          copy(input, output, Charset.defaultCharset());
      }
  
      /**
       * Copies bytes from an <code>InputStream</code> to chars on a
       * <code>Writer</code> using the specified character encoding.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       * <p>
       * This method uses {@link InputStreamReader}.
       *
       * @param input         the <code>InputStream</code> to read from
       * @param output        the <code>Writer</code> to write to
       * @param inputEncoding the encoding to use for the input stream, null means platform default
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.3
       */
      public static void copy(final InputStream input, final Writer output, final Charset inputEncoding)
              throws IOException {
          final InputStreamReader in = new InputStreamReader(input, Charsets.toCharset(inputEncoding));
          copy(in, output);
      }
  
      /**
       * Copies bytes from an <code>InputStream</code> to chars on a
       * <code>Writer</code> using the specified character encoding.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedInputStream</code>.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       * <p>
       * This method uses {@link InputStreamReader}.
       *
       * @param input         the <code>InputStream</code> to read from
       * @param output        the <code>Writer</code> to write to
       * @param inputEncoding the encoding to use for the InputStream, null means platform default
       * @throws NullPointerException                         if the input or output is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 1.1
       */
      public static void copy(final InputStream input, final Writer output, final String inputEncoding)
              throws IOException {
          copy(input, output, Charsets.toCharset(inputEncoding));
      }
  
      // copy from Reader
      //-----------------------------------------------------------------------
  
      /**
       * Copies chars from a <code>Reader</code> to a <code>Writer</code>.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       * <p>
       * Large streams (over 2GB) will return a chars copied value of
       * <code>-1</code> after the copy has completed since the correct
       * number of chars cannot be returned as an int. For large streams use the <code>copyLarge(Reader, Writer)</code> method.
       *
       * @param input  the <code>Reader</code> to read from
       * @param output the <code>Writer</code> to write to
       * @return the number of characters copied, or -1 if &gt; Integer.MAX_VALUE
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       */
      public static int copy(final Reader input, final Writer output) throws IOException {
          final long count = copyLarge(input, output);
          if (count > Integer.MAX_VALUE) {
              return -1;
          }
          return (int) count;
      }
  
      /**
       * Copies chars from a large (over 2GB) <code>Reader</code> to a <code>Writer</code>.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       * <p>
       * The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
       *
       * @param input  the <code>Reader</code> to read from
       * @param output the <code>Writer</code> to write to
       * @return the number of characters copied
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.3
       */
      public static long copyLarge(final Reader input, final Writer output) throws IOException {
          return copyLarge(input, output, new char[DEFAULT_BUFFER_SIZE]);
      }
  
      /**
       * Copies chars from a large (over 2GB) <code>Reader</code> to a <code>Writer</code>.
       * <p>
       * This method uses the provided buffer, so there is no need to use a
       * <code>BufferedReader</code>.
       * <p>
       *
       * @param input  the <code>Reader</code> to read from
       * @param output the <code>Writer</code> to write to
       * @param buffer the buffer to be used for the copy
       * @return the number of characters copied
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.2
       */
      public static long copyLarge(final Reader input, final Writer output, final char[] buffer) throws IOException {
          long count = 0;
          int n;
          while (EOF != (n = input.read(buffer))) {
              output.write(buffer, 0, n);
              count += n;
          }
          return count;
      }
  
      /**
       * Copies some or all chars from a large (over 2GB) <code>InputStream</code> to an
       * <code>OutputStream</code>, optionally skipping input chars.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       * <p>
       * The buffer size is given by {@link #DEFAULT_BUFFER_SIZE}.
       *
       * @param input       the <code>Reader</code> to read from
       * @param output      the <code>Writer</code> to write to
       * @param inputOffset : number of chars to skip from input before copying -ve values are ignored
       * @param length      : number of chars to copy. -ve means all
       * @return the number of chars copied
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.2
       */
      public static long copyLarge(final Reader input, final Writer output, final long inputOffset, final long length)
              throws IOException {
          return copyLarge(input, output, inputOffset, length, new char[DEFAULT_BUFFER_SIZE]);
      }
  
      /**
       * Copies some or all chars from a large (over 2GB) <code>InputStream</code> to an
       * <code>OutputStream</code>, optionally skipping input chars.
       * <p>
       * This method uses the provided buffer, so there is no need to use a
       * <code>BufferedReader</code>.
       * <p>
       *
       * @param input       the <code>Reader</code> to read from
       * @param output      the <code>Writer</code> to write to
       * @param inputOffset : number of chars to skip from input before copying -ve values are ignored
       * @param length      : number of chars to copy. -ve means all
       * @param buffer      the buffer to be used for the copy
       * @return the number of chars copied
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.2
       */
      public static long copyLarge(final Reader input, final Writer output, final long inputOffset, final long length,
                                   final char[] buffer)
              throws IOException {
          if (inputOffset > 0) {
              skipFully(input, inputOffset);
          }
          if (length == 0) {
              return 0;
          }
          int bytesToRead = buffer.length;
          if (length > 0 && length < buffer.length) {
              bytesToRead = (int) length;
          }
          int read;
          long totalRead = 0;
          while (bytesToRead > 0 && EOF != (read = input.read(buffer, 0, bytesToRead))) {
              output.write(buffer, 0, read);
              totalRead += read;
              if (length > 0) { // only adjust length if not reading to the end
                  // Note the cast must work because buffer.length is an integer
                  bytesToRead = (int) Math.min(length - totalRead, buffer.length);
              }
          }
          return totalRead;
      }
  
      /**
       * Copies chars from a <code>Reader</code> to bytes on an
       * <code>OutputStream</code> using the default character encoding of the
       * platform, and calling flush.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       * <p>
       * Due to the implementation of OutputStreamWriter, this method performs a flush.
       * <p>
       * This method uses {@link OutputStreamWriter}.
       *
       * @param input  the <code>Reader</code> to read from
       * @param output the <code>OutputStream</code> to write to
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       * @deprecated 2.5 use {@link #copy(Reader, OutputStream, Charset)} instead
       */
      @Deprecated
      public static void copy(final Reader input, final OutputStream output)
              throws IOException {
          copy(input, output, Charset.defaultCharset());
      }
  
      /**
       * Copies chars from a <code>Reader</code> to bytes on an
       * <code>OutputStream</code> using the specified character encoding, and
       * calling flush.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       * </p>
       * <p>
       * Due to the implementation of OutputStreamWriter, this method performs a flush.
       * </p>
       * <p>
       * This method uses {@link OutputStreamWriter}.
       * </p>
       *
       * @param input          the <code>Reader</code> to read from
       * @param output         the <code>OutputStream</code> to write to
       * @param outputEncoding the encoding to use for the OutputStream, null means platform default
       * @throws NullPointerException if the input or output is null
       * @throws IOException          if an I/O error occurs
       * @since 2.3
       */
      public static void copy(final Reader input, final OutputStream output, final Charset outputEncoding)
              throws IOException {
          final OutputStreamWriter out = new OutputStreamWriter(output, Charsets.toCharset(outputEncoding));
          copy(input, out);
          // XXX Unless anyone is planning on rewriting OutputStreamWriter,
          // we have to flush here.
          out.flush();
      }
  
      /**
       * Copies chars from a <code>Reader</code> to bytes on an
       * <code>OutputStream</code> using the specified character encoding, and
       * calling flush.
       * <p>
       * This method buffers the input internally, so there is no need to use a
       * <code>BufferedReader</code>.
       * <p>
       * Character encoding names can be found at
       * <a href="http://www.iana.org/assignments/character-sets">IANA</a>.
       * <p>
       * Due to the implementation of OutputStreamWriter, this method performs a flush.
       * <p>
       * This method uses {@link OutputStreamWriter}.
       *
       * @param input          the <code>Reader</code> to read from
       * @param output         the <code>OutputStream</code> to write to
       * @param outputEncoding the encoding to use for the OutputStream, null means platform default
       * @throws NullPointerException                         if the input or output is null
       * @throws IOException                                  if an I/O error occurs
       * @throws java.nio.charset.UnsupportedCharsetException thrown instead of {@link java.io .UnsupportedEncodingException} in version 2.2
       *                                                      if the encoding is not supported.
       * @since 1.1
       */
      public static void copy(final Reader input, final OutputStream output, final String outputEncoding)
              throws IOException {
          copy(input, output, Charsets.toCharset(outputEncoding));
      }
  
      // content equals
      //-----------------------------------------------------------------------
  
      /**
       * Compares the contents of two Streams to determine if they are equal or not.
       * <p>
       * This method buffers the input internally using
       * <code>BufferedInputStream</code> if they are not already buffered.
       *
       * @param input1 the first stream
       * @param input2 the second stream
       * @return true if the content of the streams are equal or they both don't exist, false otherwise
       * @throws NullPointerException if either input is null
       * @throws IOException          if an I/O error occurs
       */
      public static boolean contentEquals(InputStream input1, InputStream input2)
              throws IOException {
          if (input1 == input2) {
              return true;
          }
          if (!(input1 instanceof BufferedInputStream)) {
              input1 = new BufferedInputStream(input1);
          }
          if (!(input2 instanceof BufferedInputStream)) {
              input2 = new BufferedInputStream(input2);
          }
  
          int ch = input1.read();
          while (EOF != ch) {
              final int ch2 = input2.read();
              if (ch != ch2) {
                  return false;
              }
              ch = input1.read();
          }
  
          final int ch2 = input2.read();
          return ch2 == EOF;
      }
  
      /**
       * Compares the contents of two Readers to determine if they are equal or not.
       * <p>
       * This method buffers the input internally using
       * <code>BufferedReader</code> if they are not already buffered.
       *
       * @param input1 the first reader
       * @param input2 the second reader
       * @return true if the content of the readers are equal or they both don't exist, false otherwise
       * @throws NullPointerException if either input is null
       * @throws IOException          if an I/O error occurs
       * @since 1.1
       */
      public static boolean contentEquals(Reader input1, Reader input2)
              throws IOException {
          if (input1 == input2) {
              return true;
          }
  
          input1 = toBufferedReader(input1);
          input2 = toBufferedReader(input2);
  
          int ch = input1.read();
          while (EOF != ch) {
              final int ch2 = input2.read();
              if (ch != ch2) {
                  return false;
              }
              ch = input1.read();
          }
  
          final int ch2 = input2.read();
          return ch2 == EOF;
      }
  
      /**
       * Compares the contents of two Readers to determine if they are equal or not, ignoring EOL characters.
       * <p>
       * This method buffers the input internally using
       * <code>BufferedReader</code> if they are not already buffered.
       *
       * @param input1 the first reader
       * @param input2 the second reader
       * @return true if the content of the readers are equal (ignoring EOL differences),  false otherwise
       * @throws NullPointerException if either input is null
       * @throws IOException          if an I/O error occurs
       * @since 2.2
       */
      public static boolean contentEqualsIgnoreEOL(final Reader input1, final Reader input2)
              throws IOException {
          if (input1 == input2) {
              return true;
          }
          final BufferedReader br1 = toBufferedReader(input1);
          final BufferedReader br2 = toBufferedReader(input2);
  
          String line1 = br1.readLine();
          String line2 = br2.readLine();
          while (line1 != null && line2 != null && line1.equals(line2)) {
              line1 = br1.readLine();
              line2 = br2.readLine();
          }
          return line1 == null ? line2 == null ? true : false : line1.equals(line2);
      }
  
      /**
       * Skips bytes from an input byte stream. This implementation guarantees that it will read as many bytes as possible before giving up;
       * this may not always be the case for skip() implementations in subclasses of {@link InputStream}.
       * <p>
       * Note that the implementation uses {@link InputStream#read(byte[], int, int)} rather than delegating to {@link
       * InputStream#skip(long)}. This means that the method may be considerably less efficient than using the actual skip implementation,
       * this is done to guarantee that the correct number of bytes are skipped.
       * </p>
       *
       * @param input  byte stream to skip
       * @param toSkip number of bytes to skip.
       * @return number of bytes actually skipped.
       * @throws IOException              if there is a problem reading the file
       * @throws IllegalArgumentException if toSkip is negative
       * @see InputStream#skip(long)
       * @see <a href="https://issues.apache.org/jira/browse/IO-203">IO-203 - Add skipFully() method for InputStreams</a>
       * @since 2.0
       */
      public static long skip(final InputStream input, final long toSkip) throws IOException {
          if (toSkip < 0) {
              throw new IllegalArgumentException("Skip count must be non-negative, actual: " + toSkip);
          }
          /*
           * N.B. no need to synchronize this because: - we don't care if the buffer is created multiple times (the data
           * is ignored) - we always use the same size buffer, so if it it is recreated it will still be OK (if the buffer
           * size were variable, we would need to synch. to ensure some other thread did not create a smaller one)
           */
          if (SKIP_BYTE_BUFFER == null) {
              SKIP_BYTE_BUFFER = new byte[SKIP_BUFFER_SIZE];
          }
          long remain = toSkip;
          while (remain > 0) {
              // See https://issues.apache.org/jira/browse/IO-203 for why we use read() rather than delegating to skip()
              final long n = input.read(SKIP_BYTE_BUFFER, 0, (int) Math.min(remain, SKIP_BUFFER_SIZE));
              if (n < 0) { // EOF
                  break;
              }
              remain -= n;
          }
          return toSkip - remain;
      }
  
      /**
       * Skips bytes from a ReadableByteChannel. This implementation guarantees that it will read as many bytes as possible before giving up.
       *
       * @param input  ReadableByteChannel to skip
       * @param toSkip number of bytes to skip.
       * @return number of bytes actually skipped.
       * @throws IOException              if there is a problem reading the ReadableByteChannel
       * @throws IllegalArgumentException if toSkip is negative
       * @since 2.5
       */
      public static long skip(final ReadableByteChannel input, final long toSkip) throws IOException {
          if (toSkip < 0) {
              throw new IllegalArgumentException("Skip count must be non-negative, actual: " + toSkip);
          }
          final ByteBuffer skipByteBuffer = ByteBuffer.allocate((int) Math.min(toSkip, SKIP_BUFFER_SIZE));
          long remain = toSkip;
          while (remain > 0) {
              skipByteBuffer.position(0);
              skipByteBuffer.limit((int) Math.min(remain, SKIP_BUFFER_SIZE));
              final int n = input.read(skipByteBuffer);
              if (n == EOF) {
                  break;
              }
              remain -= n;
          }
          return toSkip - remain;
      }
  
      /**
       * Skips characters from an input character stream. This implementation guarantees that it will read as many characters as possible
       * before giving up; this may not always be the case for skip() implementations in subclasses of {@link Reader}.
       * <p>
       * Note that the implementation uses {@link Reader#read(char[], int, int)} rather than delegating to {@link Reader#skip(long)}. This
       * means that the method may be considerably less efficient than using the actual skip implementation, this is done to guarantee that
       * the correct number of characters are skipped.
       * </p>
       *
       * @param input  character stream to skip
       * @param toSkip number of characters to skip.
       * @return number of characters actually skipped.
       * @throws IOException              if there is a problem reading the file
       * @throws IllegalArgumentException if toSkip is negative
       * @see Reader#skip(long)
       * @see <a href="https://issues.apache.org/jira/browse/IO-203">IO-203 - Add skipFully() method for InputStreams</a>
       * @since 2.0
       */
      public static long skip(final Reader input, final long toSkip) throws IOException {
          if (toSkip < 0) {
              throw new IllegalArgumentException("Skip count must be non-negative, actual: " + toSkip);
          }
          /*
           * N.B. no need to synchronize this because: - we don't care if the buffer is created multiple times (the data
           * is ignored) - we always use the same size buffer, so if it it is recreated it will still be OK (if the buffer
           * size were variable, we would need to synch. to ensure some other thread did not create a smaller one)
           */
          if (SKIP_CHAR_BUFFER == null) {
              SKIP_CHAR_BUFFER = new char[SKIP_BUFFER_SIZE];
          }
          long remain = toSkip;
          while (remain > 0) {
              // See https://issues.apache.org/jira/browse/IO-203 for why we use read() rather than delegating to skip()
              final long n = input.read(SKIP_CHAR_BUFFER, 0, (int) Math.min(remain, SKIP_BUFFER_SIZE));
              if (n < 0) { // EOF
                  break;
              }
              remain -= n;
          }
          return toSkip - remain;
      }
  
      /**
       * Skips the requested number of bytes or fail if there are not enough left.
       * <p>
       * This allows for the possibility that {@link InputStream#skip(long)} may not skip as many bytes as requested (most likely because of
       * reaching EOF).
       * <p>
       * Note that the implementation uses {@link #skip(InputStream, long)}. This means that the method may be considerably less efficient
       * than using the actual skip implementation, this is done to guarantee that the correct number of characters are skipped.
       * </p>
       *
       * @param input  stream to skip
       * @param toSkip the number of bytes to skip
       * @throws IOException              if there is a problem reading the file
       * @throws IllegalArgumentException if toSkip is negative
       * @throws EOFException             if the number of bytes skipped was incorrect
       * @see InputStream#skip(long)
       * @since 2.0
       */
      public static void skipFully(final InputStream input, final long toSkip) throws IOException {
          if (toSkip < 0) {
              throw new IllegalArgumentException("Bytes to skip must not be negative: " + toSkip);
          }
          final long skipped = skip(input, toSkip);
          if (skipped != toSkip) {
              throw new EOFException("Bytes to skip: " + toSkip + " actual: " + skipped);
          }
      }
  
      /**
       * Skips the requested number of bytes or fail if there are not enough left.
       *
       * @param input  ReadableByteChannel to skip
       * @param toSkip the number of bytes to skip
       * @throws IOException              if there is a problem reading the ReadableByteChannel
       * @throws IllegalArgumentException if toSkip is negative
       * @throws EOFException             if the number of bytes skipped was incorrect
       * @since 2.5
       */
      public static void skipFully(final ReadableByteChannel input, final long toSkip) throws IOException {
          if (toSkip < 0) {
              throw new IllegalArgumentException("Bytes to skip must not be negative: " + toSkip);
          }
          final long skipped = skip(input, toSkip);
          if (skipped != toSkip) {
              throw new EOFException("Bytes to skip: " + toSkip + " actual: " + skipped);
          }
      }
  
      /**
       * Skips the requested number of characters or fail if there are not enough left.
       * <p>
       * This allows for the possibility that {@link Reader#skip(long)} may not skip as many characters as requested (most likely because of
       * reaching EOF).
       * <p>
       * Note that the implementation uses {@link #skip(Reader, long)}. This means that the method may be considerably less efficient than
       * using the actual skip implementation, this is done to guarantee that the correct number of characters are skipped.
       * </p>
       *
       * @param input  stream to skip
       * @param toSkip the number of characters to skip
       * @throws IOException              if there is a problem reading the file
       * @throws IllegalArgumentException if toSkip is negative
       * @throws EOFException             if the number of characters skipped was incorrect
       * @see Reader#skip(long)
       * @since 2.0
       */
      public static void skipFully(final Reader input, final long toSkip) throws IOException {
          final long skipped = skip(input, toSkip);
          if (skipped != toSkip) {
              throw new EOFException("Chars to skip: " + toSkip + " actual: " + skipped);
          }
      }
  
      /**
       * Reads characters from an input character stream. This implementation guarantees that it will read as many characters as possible
       * before giving up; this may not always be the case for subclasses of {@link Reader}.
       *
       * @param input  where to read input from
       * @param buffer destination
       * @param offset initial offset into buffer
       * @param length length to read, must be &gt;= 0
       * @return actual length read; may be less than requested if EOF was reached
       * @throws IOException if a read error occurs
       * @since 2.2
       */
      public static int read(final Reader input, final char[] buffer, final int offset, final int length)
              throws IOException {
          if (length < 0) {
              throw new IllegalArgumentException("Length must not be negative: " + length);
          }
          int remaining = length;
          while (remaining > 0) {
              final int location = length - remaining;
              final int count = input.read(buffer, offset + location, remaining);
              if (EOF == count) { // EOF
                  break;
              }
              remaining -= count;
          }
          return length - remaining;
      }
  
      /**
       * Reads characters from an input character stream. This implementation guarantees that it will read as many characters as possible
       * before giving up; this may not always be the case for subclasses of {@link Reader}.
       *
       * @param input  where to read input from
       * @param buffer destination
       * @return actual length read; may be less than requested if EOF was reached
       * @throws IOException if a read error occurs
       * @since 2.2
       */
      public static int read(final Reader input, final char[] buffer) throws IOException {
          return read(input, buffer, 0, buffer.length);
      }
  
      /**
       * Reads bytes from an input stream. This implementation guarantees that it will read as many bytes as possible before giving up; this
       * may not always be the case for subclasses of {@link InputStream}.
       *
       * @param input  where to read input from
       * @param buffer destination
       * @param offset initial offset into buffer
       * @param length length to read, must be &gt;= 0
       * @return actual length read; may be less than requested if EOF was reached
       * @throws IOException if a read error occurs
       * @since 2.2
       */
      public static int read(final InputStream input, final byte[] buffer, final int offset, final int length)
              throws IOException {
          if (length < 0) {
              throw new IllegalArgumentException("Length must not be negative: " + length);
          }
          int remaining = length;
          while (remaining > 0) {
              final int location = length - remaining;
              final int count = input.read(buffer, offset + location, remaining);
              if (EOF == count) { // EOF
                  break;
              }
              remaining -= count;
          }
          return length - remaining;
      }
  
      /**
       * Reads bytes from an input stream. This implementation guarantees that it will read as many bytes as possible before giving up; this
       * may not always be the case for subclasses of {@link InputStream}.
       *
       * @param input  where to read input from
       * @param buffer destination
       * @return actual length read; may be less than requested if EOF was reached
       * @throws IOException if a read error occurs
       * @since 2.2
       */
      public static int read(final InputStream input, final byte[] buffer) throws IOException {
          return read(input, buffer, 0, buffer.length);
      }
  
      /**
       * Reads bytes from a ReadableByteChannel.
       * <p>
       * This implementation guarantees that it will read as many bytes as possible before giving up; this may not always be the case for
       * subclasses of {@link ReadableByteChannel}.
       *
       * @param input  the byte channel to read
       * @param buffer byte buffer destination
       * @return the actual length read; may be less than requested if EOF was reached
       * @throws IOException if a read error occurs
       * @since 2.5
       */
      public static int read(final ReadableByteChannel input, final ByteBuffer buffer) throws IOException {
          final int length = buffer.remaining();
          while (buffer.remaining() > 0) {
              final int count = input.read(buffer);
              if (EOF == count) { // EOF
                  break;
              }
          }
          return length - buffer.remaining();
      }
  
      /**
       * Reads the requested number of characters or fail if there are not enough left.
       * <p>
       * This allows for the possibility that {@link Reader#read(char[], int, int)} may not read as many characters as requested (most likely
       * because of reaching EOF).
       *
       * @param input  where to read input from
       * @param buffer destination
       * @param offset initial offset into buffer
       * @param length length to read, must be &gt;= 0
       * @throws IOException              if there is a problem reading the file
       * @throws IllegalArgumentException if length is negative
       * @throws EOFException             if the number of characters read was incorrect
       * @since 2.2
       */
      public static void readFully(final Reader input, final char[] buffer, final int offset, final int length)
              throws IOException {
          final int actual = read(input, buffer, offset, length);
          if (actual != length) {
              throw new EOFException("Length to read: " + length + " actual: " + actual);
          }
      }
  
      /**
       * Reads the requested number of characters or fail if there are not enough left.
       * <p>
       * This allows for the possibility that {@link Reader#read(char[], int, int)} may not read as many characters as requested (most likely
       * because of reaching EOF).
       *
       * @param input  where to read input from
       * @param buffer destination
       * @throws IOException              if there is a problem reading the file
       * @throws IllegalArgumentException if length is negative
       * @throws EOFException             if the number of characters read was incorrect
       * @since 2.2
       */
      public static void readFully(final Reader input, final char[] buffer) throws IOException {
          readFully(input, buffer, 0, buffer.length);
      }
  
      /**
       * Reads the requested number of bytes or fail if there are not enough left.
       * <p>
       * This allows for the possibility that {@link InputStream#read(byte[], int, int)} may not read as many bytes as requested (most likely
       * because of reaching EOF).
       *
       * @param input  where to read input from
       * @param buffer destination
       * @param offset initial offset into buffer
       * @param length length to read, must be &gt;= 0
       * @throws IOException              if there is a problem reading the file
       * @throws IllegalArgumentException if length is negative
       * @throws EOFException             if the number of bytes read was incorrect
       * @since 2.2
       */
      public static void readFully(final InputStream input, final byte[] buffer, final int offset, final int length)
              throws IOException {
          final int actual = read(input, buffer, offset, length);
          if (actual != length) {
              throw new EOFException("Length to read: " + length + " actual: " + actual);
          }
      }
  
      /**
       * Reads the requested number of bytes or fail if there are not enough left.
       * <p>
       * This allows for the possibility that {@link InputStream#read(byte[], int, int)} may not read as many bytes as requested (most likely
       * because of reaching EOF).
       *
       * @param input  where to read input from
       * @param buffer destination
       * @throws IOException              if there is a problem reading the file
       * @throws IllegalArgumentException if length is negative
       * @throws EOFException             if the number of bytes read was incorrect
       * @since 2.2
       */
      public static void readFully(final InputStream input, final byte[] buffer) throws IOException {
          readFully(input, buffer, 0, buffer.length);
      }
  
      /**
       * Reads the requested number of bytes or fail if there are not enough left.
       * <p>
       * This allows for the possibility that {@link InputStream#read(byte[], int, int)} may not read as many bytes as requested (most likely
       * because of reaching EOF).
       *
       * @param input  where to read input from
       * @param length length to read, must be &gt;= 0
       * @return the bytes read from input
       * @throws IOException              if there is a problem reading the file
       * @throws IllegalArgumentException if length is negative
       * @throws EOFException             if the number of bytes read was incorrect
       * @since 2.5
       */
      public static byte[] readFully(final InputStream input, final int length) throws IOException {
          final byte[] buffer = new byte[length];
          readFully(input, buffer, 0, buffer.length);
          return buffer;
      }
  
      /**
       * Reads the requested number of bytes or fail if there are not enough left.
       * <p>
       * This allows for the possibility that {@link ReadableByteChannel#read(ByteBuffer)} may not read as many bytes as requested (most
       * likely because of reaching EOF).
       *
       * @param input  the byte channel to read
       * @param buffer byte buffer destination
       * @throws IOException  if there is a problem reading the file
       * @throws EOFException if the number of bytes read was incorrect
       * @since 2.5
       */
      public static void readFully(final ReadableByteChannel input, final ByteBuffer buffer) throws IOException {
          final int expected = buffer.remaining();
          final int actual = read(input, buffer);
          if (actual != expected) {
              throw new EOFException("Length to read: " + expected + " actual: " + actual);
          }
      }
  
  }
  