content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   * 
   *      http://www.apache.org/licenses/LICENSE-2.0
   * 
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package org.apache.commons.codec.binary;
  
  import java.io.UnsupportedEncodingException;
  
  import org.apache.commons.codec.CharEncoding;
  
  /**
   * Converts String to and from bytes using the encodings required by the Java specification. These encodings are specified in <a
   * href="http://java.sun.com/j2se/1.4.2/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
   * 
   * @see CharEncoding
   * @see <a href="http://java.sun.com/j2se/1.4.2/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
   * @author <a href="mailto:ggregory@seagullsw.com">Gary Gregory</a>
   * @version $Id: StringUtils.java 950460 2010-06-02 09:43:02Z sebb $
   * @since 1.4
   */
  public class StringUtils {
  
      /**
       * Encodes the given string into a sequence of bytes using the ISO-8859-1 charset, storing the result into a new
       * byte array.
       * 
       * @param string
       *            the String to encode, may be <code>null</code>
       * @return encoded bytes, or <code>null</code> if the input string was <code>null</code>
       * @throws IllegalStateException
       *             Thrown when the charset is missing, which should be never according the the Java specification.
       * @see <a href="http://java.sun.com/j2se/1.4.2/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
       * @see #getBytesUnchecked(String, String)
       */
      public static byte[] getBytesIso8859_1(String string) {
          return StringUtils.getBytesUnchecked(string, CharEncoding.ISO_8859_1);
      }
  
      /**
       * Encodes the given string into a sequence of bytes using the US-ASCII charset, storing the result into a new byte
       * array.
       * 
       * @param string
       *            the String to encode, may be <code>null</code>
       * @return encoded bytes, or <code>null</code> if the input string was <code>null</code>
       * @throws IllegalStateException
       *             Thrown when the charset is missing, which should be never according the the Java specification.
       * @see <a href="http://java.sun.com/j2se/1.4.2/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
       * @see #getBytesUnchecked(String, String)
       */
      public static byte[] getBytesUsAscii(String string) {
          return StringUtils.getBytesUnchecked(string, CharEncoding.US_ASCII);
      }
  
      /**
       * Encodes the given string into a sequence of bytes using the UTF-16 charset, storing the result into a new byte
       * array.
       * 
       * @param string
       *            the String to encode, may be <code>null</code>
       * @return encoded bytes, or <code>null</code> if the input string was <code>null</code>
       * @throws IllegalStateException
       *             Thrown when the charset is missing, which should be never according the the Java specification.
       * @see <a href="http://java.sun.com/j2se/1.4.2/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
       * @see #getBytesUnchecked(String, String)
       */
      public static byte[] getBytesUtf16(String string) {
          return StringUtils.getBytesUnchecked(string, CharEncoding.UTF_16);
      }
  
      /**
       * Encodes the given string into a sequence of bytes using the UTF-16BE charset, storing the result into a new byte
       * array.
       * 
       * @param string
       *            the String to encode, may be <code>null</code>
       * @return encoded bytes, or <code>null</code> if the input string was <code>null</code>
       * @throws IllegalStateException
       *             Thrown when the charset is missing, which should be never according the the Java specification.
       * @see <a href="http://java.sun.com/j2se/1.4.2/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
       * @see #getBytesUnchecked(String, String)
       */
      public static byte[] getBytesUtf16Be(String string) {
          return StringUtils.getBytesUnchecked(string, CharEncoding.UTF_16BE);
      }
  
      /**
       * Encodes the given string into a sequence of bytes using the UTF-16LE charset, storing the result into a new byte
       * array.
       * 
       * @param string
       *            the String to encode, may be <code>null</code>
       * @return encoded bytes, or <code>null</code> if the input string was <code>null</code>
       * @throws IllegalStateException
       *             Thrown when the charset is missing, which should be never according the the Java specification.
       * @see <a href="http://java.sun.com/j2se/1.4.2/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
       * @see #getBytesUnchecked(String, String)
       */
      public static byte[] getBytesUtf16Le(String string) {
          return StringUtils.getBytesUnchecked(string, CharEncoding.UTF_16LE);
      }
  
      /**
       * Encodes the given string into a sequence of bytes using the UTF-8 charset, storing the result into a new byte
       * array.
       * 
       * @param string
       *            the String to encode, may be <code>null</code>
       * @return encoded bytes, or <code>null</code> if the input string was <code>null</code>
       * @throws IllegalStateException
       *             Thrown when the charset is missing, which should be never according the the Java specification.
       * @see <a href="http://java.sun.com/j2se/1.4.2/docs/api/java/nio/charset/Charset.html">Standard charsets</a>
       * @see #getBytesUnchecked(String, String)
       */
      public static byte[] getBytesUtf8(String string) {
          return StringUtils.getBytesUnchecked(string, CharEncoding.UTF_8);
      }
  
      /**
       * Encodes the given string into a sequence of bytes using the named charset, storing the result into a new byte
       * array.
       * <p>
       * This method catches {@link UnsupportedEncodingException} and rethrows it as {@link IllegalStateException}, which
       * should never happen for a required charset name. Use this method when the encoding is required to be in the JRE.
       * </p>
       * 
       * @param string
       *            the String to encode, may be <code>null</code>
       * @param charsetName
       *            The name of a required {@link java.nio.charset.Charset}
       * @return encoded bytes, or <code>null</code> if the input string was <code>null</code>
       * @throws IllegalStateException
       *             Thrown when a {@link UnsupportedEncodingException} is caught, which should never happen for a
       *             required charset name.
       * @see CharEncoding
       * @see String#getBytes(String)
       */
      public static byte[] getBytesUnchecked(String string, String charsetName) {
          if (string == null) {
              return null;
          }
          try {
              return string.getBytes(charsetName);
          } catch (UnsupportedEncodingException e) {
              throw StringUtils.newIllegalStateException(charsetName, e);
          }
      }
  
      private static IllegalStateException newIllegalStateException(String charsetName, UnsupportedEncodingException e) {
          return new IllegalStateException(charsetName + ": " + e);
      }
  
      /**
       * Constructs a new <code>String</code> by decoding the specified array of bytes using the given charset.
       * <p>
       * This method catches {@link UnsupportedEncodingException} and re-throws it as {@link IllegalStateException}, which
       * should never happen for a required charset name. Use this method when the encoding is required to be in the JRE.
       * </p>
       * 
       * @param bytes
       *            The bytes to be decoded into characters, may be <code>null</code>
       * @param charsetName
       *            The name of a required {@link java.nio.charset.Charset}
       * @return A new <code>String</code> decoded from the specified array of bytes using the given charset,
       *         or <code>null</code> if the input byte arrray was <code>null</code>.
       * @throws IllegalStateException
       *             Thrown when a {@link UnsupportedEncodingException} is caught, which should never happen for a
       *             required charset name.
       * @see CharEncoding
       * @see String#String(byte[], String)
       */
      public static String newString(byte[] bytes, String charsetName) {
          if (bytes == null) {
              return null;
          }
          try {
              return new String(bytes, charsetName);
          } catch (UnsupportedEncodingException e) {
              throw StringUtils.newIllegalStateException(charsetName, e);
          }
      }
  
      /**
       * Constructs a new <code>String</code> by decoding the specified array of bytes using the ISO-8859-1 charset.
       * 
       * @param bytes
       *            The bytes to be decoded into characters, may be <code>null</code>
       * @return A new <code>String</code> decoded from the specified array of bytes using the ISO-8859-1 charset,
       *         or <code>null</code> if the input byte array was <code>null</code>.
       * @throws IllegalStateException
       *             Thrown when a {@link UnsupportedEncodingException} is caught, which should never happen since the
       *             charset is required.
       */
      public static String newStringIso8859_1(byte[] bytes) {
          return StringUtils.newString(bytes, CharEncoding.ISO_8859_1);
      }
  
      /**
       * Constructs a new <code>String</code> by decoding the specified array of bytes using the US-ASCII charset.
       * 
       * @param bytes
       *            The bytes to be decoded into characters
       * @return A new <code>String</code> decoded from the specified array of bytes using the US-ASCII charset,
       *         or <code>null</code> if the input byte array was <code>null</code>.
       * @throws IllegalStateException
       *             Thrown when a {@link UnsupportedEncodingException} is caught, which should never happen since the
       *             charset is required.
       */
      public static String newStringUsAscii(byte[] bytes) {
          return StringUtils.newString(bytes, CharEncoding.US_ASCII);
      }
  
      /**
       * Constructs a new <code>String</code> by decoding the specified array of bytes using the UTF-16 charset.
       * 
       * @param bytes
       *            The bytes to be decoded into characters
       * @return A new <code>String</code> decoded from the specified array of bytes using the UTF-16 charset
       *         or <code>null</code> if the input byte array was <code>null</code>.
       * @throws IllegalStateException
       *             Thrown when a {@link UnsupportedEncodingException} is caught, which should never happen since the
       *             charset is required.
       */
      public static String newStringUtf16(byte[] bytes) {
          return StringUtils.newString(bytes, CharEncoding.UTF_16);
      }
  
      /**
       * Constructs a new <code>String</code> by decoding the specified array of bytes using the UTF-16BE charset.
       * 
       * @param bytes
       *            The bytes to be decoded into characters
       * @return A new <code>String</code> decoded from the specified array of bytes using the UTF-16BE charset,
       *         or <code>null</code> if the input byte array was <code>null</code>.
       * @throws IllegalStateException
       *             Thrown when a {@link UnsupportedEncodingException} is caught, which should never happen since the
       *             charset is required.
       */
      public static String newStringUtf16Be(byte[] bytes) {
          return StringUtils.newString(bytes, CharEncoding.UTF_16BE);
      }
  
      /**
       * Constructs a new <code>String</code> by decoding the specified array of bytes using the UTF-16LE charset.
       * 
       * @param bytes
       *            The bytes to be decoded into characters
       * @return A new <code>String</code> decoded from the specified array of bytes using the UTF-16LE charset,
       *         or <code>null</code> if the input byte array was <code>null</code>.
       * @throws IllegalStateException
       *             Thrown when a {@link UnsupportedEncodingException} is caught, which should never happen since the
       *             charset is required.
       */
      public static String newStringUtf16Le(byte[] bytes) {
          return StringUtils.newString(bytes, CharEncoding.UTF_16LE);
      }
  
      /**
       * Constructs a new <code>String</code> by decoding the specified array of bytes using the UTF-8 charset.
       * 
       * @param bytes
       *            The bytes to be decoded into characters
       * @return A new <code>String</code> decoded from the specified array of bytes using the UTF-8 charset,
       *         or <code>null</code> if the input byte array was <code>null</code>.
       * @throws IllegalStateException
       *             Thrown when a {@link UnsupportedEncodingException} is caught, which should never happen since the
       *             charset is required.
       */
      public static String newStringUtf8(byte[] bytes) {
          return StringUtils.newString(bytes, CharEncoding.UTF_8);
      }
  
  }
  