content: package org.android.share.utils;
  
  //EPL, Eclipse Public License, V1.0 or later, http://www.eclipse.org/legal
  //LGPL, GNU Lesser General Public License, V2.1 or later, http://www.gnu.org/licenses/lgpl.html
  //GPL, GNU General Public License, V2 or later, http://www.gnu.org/licenses/gpl.html
  //AL, Apache License, V2.0 or later, http://www.apache.org/licenses
  //BSD, BSD License, http://www.opensource.org/licenses/bsd-license.php
  /**
   * A Base64 encoder/decoder.
   *
   * <p>
   * This class is used to encode and decode data in Base64 format as described in RFC 1521.
   *
   * <p>
   * Project home page: <a href="http://www.source-code.biz/base64coder/java/">www.source-code.biz/base64coder/java</a><br>
   * Author: Christian d'Heureuse, Inventec Informatik AG, Zurich, Switzerland<br>
   * Multi-licensed: EPL / LGPL / GPL / AL / BSD.
   *
   *
   * @author XiaoMa
   * @Title: Base64Coder.java
   * @Package com.xiaoma.piccut.demo
   * @Description: TODO
   */
  
  public class Base64Coder {
  
      //The line separator string of the operating system.
      private static final String systemLineSeparator = System.getProperty("line.separator");
  
      //Mapping table from 6-bit nibbles to Base64 characters.
      private static char[] map1 = new char[64];
  
      static {
          int i = 0;
          for (char c = 'A'; c <= 'Z'; c++) {
              map1[i++] = c;
          }
          for (char c = 'a'; c <= 'z'; c++) {
              map1[i++] = c;
          }
          for (char c = '0'; c <= '9'; c++) {
              map1[i++] = c;
          }
          map1[i++] = '+';
          map1[i++] = '/';
      }
  
      //Mapping table from Base64 characters to 6-bit nibbles.
      private static byte[] map2 = new byte[128];
  
      static {
          for (int i = 0; i < map2.length; i++) {
              map2[i] = -1;
          }
          for (int i = 0; i < 64; i++) {
              map2[map1[i]] = (byte) i;
          }
      }
  
      /**
       * Encodes a string into Base64 format.
       * No blanks or line breaks are inserted.
       *
       * @param s A String to be encoded.
       * @return A String containing the Base64 encoded data.
       */
      public static String encodeString(String s) {
          return new String(encode(s.getBytes()));
      }
  
      /**
       * Encodes a byte array into Base 64 format and breaks the output into lines of 76 characters.
       * This method is compatible with <code>sun.misc.BASE64Encoder.encodeBuffer(byte[])</code>.
       *
       * @param in An array containing the data bytes to be encoded.
       * @return A String containing the Base64 encoded data, broken into lines.
       */
      public static String encodeLines(byte[] in) {
          return encodeLines(in, 0, in.length, 76, systemLineSeparator);
      }
  
      /**
       * Encodes a byte array into Base 64 format and breaks the output into lines.
       *
       * @param in            An array containing the data bytes to be encoded.
       * @param iOff          Offset of the first byte in <code>in</code> to be processed.
       * @param iLen          Number of bytes to be processed in <code>in</code>, starting at <code>iOff</code>.
       * @param lineLen       Line length for the output data. Should be a multiple of 4.
       * @param lineSeparator The line separator to be used to separate the output lines.
       * @return A String containing the Base64 encoded data, broken into lines.
       */
      public static String encodeLines(byte[] in, int iOff, int iLen, int lineLen, String lineSeparator) {
          int blockLen = (lineLen * 3) / 4;
          if (blockLen <= 0) {
              throw new IllegalArgumentException();
          }
          int lines = (iLen + blockLen - 1) / blockLen;
          int bufLen = ((iLen + 2) / 3) * 4 + lines * lineSeparator.length();
          StringBuilder buf = new StringBuilder(bufLen);
          int ip = 0;
          while (ip < iLen) {
              int l = Math.min(iLen - ip, blockLen);
              buf.append(encode(in, iOff + ip, l));
              buf.append(lineSeparator);
              ip += l;
          }
          return buf.toString();
      }
  
      /**
       * Encodes a byte array into Base64 format.
       * No blanks or line breaks are inserted in the output.
       *
       * @param in An array containing the data bytes to be encoded.
       * @return A character array containing the Base64 encoded data.
       */
      public static char[] encode(byte[] in) {
          return encode(in, 0, in.length);
      }
  
      /**
       * Encodes a byte array into Base64 format.
       * No blanks or line breaks are inserted in the output.
       *
       * @param in   An array containing the data bytes to be encoded.
       * @param iLen Number of bytes to process in <code>in</code>.
       * @return A character array containing the Base64 encoded data.
       */
      public static char[] encode(byte[] in, int iLen) {
          return encode(in, 0, iLen);
      }
  
      /**
       * Encodes a byte array into Base64 format.
       * No blanks or line breaks are inserted in the output.
       *
       * @param in   An array containing the data bytes to be encoded.
       * @param iOff Offset of the first byte in <code>in</code> to be processed.
       * @param iLen Number of bytes to process in <code>in</code>, starting at <code>iOff</code>.
       * @return A character array containing the Base64 encoded data.
       */
      public static char[] encode(byte[] in, int iOff, int iLen) {
          int oDataLen = (iLen * 4 + 2) / 3;       // output length without padding
          int oLen = ((iLen + 2) / 3) * 4;         // output length including padding
          char[] out = new char[oLen];
          int ip = iOff;
          int iEnd = iOff + iLen;
          int op = 0;
          while (ip < iEnd) {
              int i0 = in[ip++] & 0xff;
              int i1 = ip < iEnd ? in[ip++] & 0xff : 0;
              int i2 = ip < iEnd ? in[ip++] & 0xff : 0;
              int o0 = i0 >>> 2;
              int o1 = ((i0 & 3) << 4) | (i1 >>> 4);
              int o2 = ((i1 & 0xf) << 2) | (i2 >>> 6);
              int o3 = i2 & 0x3F;
              out[op++] = map1[o0];
              out[op++] = map1[o1];
              out[op] = op < oDataLen ? map1[o2] : '=';
              op++;
              out[op] = op < oDataLen ? map1[o3] : '=';
              op++;
          }
          return out;
      }
  
      /**
       * Decodes a string from Base64 format.
       * No blanks or line breaks are allowed within the Base64 encoded input data.
       *
       * @param s A Base64 String to be decoded.
       * @return A String containing the decoded data.
       * @throws IllegalArgumentException If the input is not valid Base64 encoded data.
       */
      public static String decodeString(String s) {
          return new String(decode(s));
      }
  
      /**
       * Decodes a byte array from Base64 format and ignores line separators, tabs and blanks.
       * CR, LF, Tab and Space characters are ignored in the input data.
       * This method is compatible with <code>sun.misc.BASE64Decoder.decodeBuffer(String)</code>.
       *
       * @param s A Base64 String to be decoded.
       * @return An array containing the decoded data bytes.
       * @throws IllegalArgumentException If the input is not valid Base64 encoded data.
       */
      public static byte[] decodeLines(String s) {
          char[] buf = new char[s.length() + 3];
          int p = 0;
          for (int ip = 0; ip < s.length(); ip++) {
              char c = s.charAt(ip);
              if (c != ' ' && c != '\r' && c != '\n' && c != '\t') {
                  buf[p++] = c;
              }
          }
          while ((p % 4) != 0) {
              buf[p++] = '0';
          }
  
          return decode(buf, 0, p);
      }
  
      /**
       * Decodes a byte array from Base64 format.
       * No blanks or line breaks are allowed within the Base64 encoded input data.
       *
       * @param s A Base64 String to be decoded.
       * @return An array containing the decoded data bytes.
       * @throws IllegalArgumentException If the input is not valid Base64 encoded data.
       */
      public static byte[] decode(String s) {
          return decode(s.toCharArray());
      }
  
      /**
       * Decodes a byte array from Base64 format.
       * No blanks or line breaks are allowed within the Base64 encoded input data.
       *
       * @param in A character array containing the Base64 encoded data.
       * @return An array containing the decoded data bytes.
       * @throws IllegalArgumentException If the input is not valid Base64 encoded data.
       */
      public static byte[] decode(char[] in) {
          return decode(in, 0, in.length);
      }
  
      /**
       * Decodes a byte array from Base64 format.
       * No blanks or line breaks are allowed within the Base64 encoded input data.
       *
       * @param in   A character array containing the Base64 encoded data.
       * @param iOff Offset of the first character in <code>in</code> to be processed.
       * @param iLen Number of characters to process in <code>in</code>, starting at <code>iOff</code>.
       * @return An array containing the decoded data bytes.
       * @throws IllegalArgumentException If the input is not valid Base64 encoded data.
       */
      public static byte[] decode(char[] in, int iOff, int iLen) {
          if (iLen % 4 != 0) {
              throw new IllegalArgumentException("Length of Base64 encoded input string is not a multiple of 4.");
          }
          while (iLen > 0 && in[iOff + iLen - 1] == '=') {
              iLen--;
          }
          int oLen = (iLen * 3) / 4;
          byte[] out = new byte[oLen];
          int ip = iOff;
          int iEnd = iOff + iLen;
          int op = 0;
          while (ip < iEnd) {
              int i0 = in[ip++];
              int i1 = in[ip++];
              int i2 = ip < iEnd ? in[ip++] : 'A';
              int i3 = ip < iEnd ? in[ip++] : 'A';
              if (i0 > 127 || i1 > 127 || i2 > 127 || i3 > 127) {
                  throw new IllegalArgumentException("Illegal character in Base64 encoded data.");
              }
              int b0 = map2[i0];
              int b1 = map2[i1];
              int b2 = map2[i2];
              int b3 = map2[i3];
              if (b0 < 0 || b1 < 0 || b2 < 0 || b3 < 0) {
                  throw new IllegalArgumentException("Illegal character in Base64 encoded data.");
              }
              int o0 = (b0 << 2) | (b1 >>> 4);
              int o1 = ((b1 & 0xf) << 4) | (b2 >>> 2);
              int o2 = ((b2 & 3) << 6) | b3;
              out[op++] = (byte) o0;
              if (op < oLen) {
                  out[op++] = (byte) o1;
              }
              if (op < oLen) {
                  out[op++] = (byte) o2;
              }
          }
          return out;
      }
  
      //Dummy constructor.
      private Base64Coder() {
      }
  
  } // end class 