base64.java.svn-base

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                        | ((DECODABET[source[srcOffset + 3]] & 0xFF));


                destination[destOffset] = (byte)(outBuff >> 16);
                destination[destOffset + 1] = (byte)(outBuff >> 8);
                destination[destOffset + 2] = (byte)(outBuff);

                return 3;
            }
            catch (Exception e) {
                System.out.println("" + source[srcOffset] + ": " + (DECODABET[source[srcOffset]]));
                System.out.println("" + source[srcOffset + 1] + ": " + (DECODABET[source[srcOffset + 1]]));
                System.out.println("" + source[srcOffset + 2] + ": " + (DECODABET[source[srcOffset + 2]]));
                System.out.println("" + source[srcOffset + 3] + ": " + (DECODABET[source[srcOffset + 3]]));
                return -1;
            }   //e nd catch
        }
    }   // end decodeToBytes


    /**
     * Very low-level access to decoding ASCII characters in
     * the form of a byte array. Does not support automatically
     * gunzipping or any other "fancy" features.
     *
     * @param source The Base64 encoded data
     * @param off    The offset of where to begin decoding
     * @param len    The length of characters to decode
     * @return decoded data
     * @since 1.3
     */
    public static byte[] decode(byte[] source, int off, int len) {
        int len34 = len * 3 / 4;
        byte[] outBuff = new byte[len34]; // Upper limit on size of output
        int outBuffPosn = 0;

        byte[] b4 = new byte[4];
        int b4Posn = 0;
        int i = 0;
        byte sbiCrop = 0;
        byte sbiDecode = 0;
        for (i = off; i < off + len; i++) {
            sbiCrop = (byte)(source[i] & 0x7f); // Only the low seven bits
            sbiDecode = DECODABET[sbiCrop];

            if (sbiDecode >= WHITE_SPACE_ENC) // White space, Equals sign or better
            {
                if (sbiDecode >= EQUALS_SIGN_ENC) {
                    b4[b4Posn++] = sbiCrop;
                    if (b4Posn > 3) {
                        outBuffPosn += decode4to3(b4, 0, outBuff, outBuffPosn);
                        b4Posn = 0;

                        // If that was the equals sign, break out of 'for' loop
                        if (sbiCrop == EQUALS_SIGN)
                            break;
                    }   // end if: quartet built

                }   // end if: equals sign or better

            }   // end if: white space, equals sign or better
            else {
                System.err.println("Bad Base64 input character at " + i + ": " + source[i] + "(decimal)");
                return null;
            }   // end else:
        }   // each input character

        byte[] out = new byte[outBuffPosn];
        System.arraycopy(outBuff, 0, out, 0, outBuffPosn);
        return out;
    }   // end decode


    /**
     * Decodes data from Base64 notation, automatically
     * detecting gzip-compressed data and decompressing it.
     *
     * @param s the string to decode
     * @return the decoded data
     * @since 1.4
     */
    public static byte[] decode(String s) {
        byte[] bytes;
        try {
            bytes = s.getBytes(PREFERRED_ENCODING);
        }   // end try
        catch (java.io.UnsupportedEncodingException uee) {
            bytes = s.getBytes();
        }   // end catch
        //</change>

        // Decode
        bytes = decode(bytes, 0, bytes.length);

        // Check to see if it's gzip-compressed
        // GZIP Magic Two-Byte Number: 0x8b1f (35615)
        if (bytes.length >= 2) {

            int head = ((int)bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00);
            if (
                    bytes != null && // In case decoding returned null
                            bytes.length >= 4 && // Don't want to get ArrayIndexOutOfBounds exception
                            java.util.zip.GZIPInputStream.GZIP_MAGIC == head) {
                java.io.ByteArrayInputStream bais = null;
                java.util.zip.GZIPInputStream gzis = null;
                java.io.ByteArrayOutputStream baos = null;
                byte[] buffer = new byte[2048];
                int length = 0;

                try {
                    baos = new java.io.ByteArrayOutputStream();
                    bais = new java.io.ByteArrayInputStream(bytes);
                    gzis = new java.util.zip.GZIPInputStream(bais);

                    while ((length = gzis.read(buffer)) >= 0) {
                        baos.write(buffer, 0, length);
                    }   // end while: reading input

                    // No error? Get new bytes.
                    bytes = baos.toByteArray();

                }   // end try
                catch (java.io.IOException e) {
                    // Just return originally-decoded bytes
                }   // end catch
                finally {
                    try {
                        baos.close();
                    }
                    catch (Exception e) {
                    }
                    try {
                        gzis.close();
                    }
                    catch (Exception e) {
                    }
                    try {
                        bais.close();
                    }
                    catch (Exception e) {
                    }
                }   // end finally

            }   // end if: gzipped
        }   // end if: bytes.length >= 2

        return bytes;
    }   // end decode


    /**
     * Attempts to decode Base64 data and deserialize a Java
     * Object within. Returns <tt>null</tt> if there was an error.
     *
     * @param encodedObject The Base64 data to decode
     * @return The decoded and deserialized object
     * @since 1.5
     */
    public static Object decodeToObject(String encodedObject) {
        // Decode and gunzip if necessary
        byte[] objBytes = decode(encodedObject);

        java.io.ByteArrayInputStream bais = null;
        java.io.ObjectInputStream ois = null;
        Object obj = null;

        try {
            bais = new java.io.ByteArrayInputStream(objBytes);
            ois = new java.io.ObjectInputStream(bais);

            obj = ois.readObject();
        }   // end try
        catch (java.io.IOException e) {
            Log.error(e);
            obj = null;
        }   // end catch
        catch (java.lang.ClassNotFoundException e) {
            Log.error(e);
            obj = null;
        }   // end catch
        finally {
            try {
                bais.close();
            }
            catch (Exception e) {
            }
            try {
                ois.close();
            }
            catch (Exception e) {
            }
        }   // end finally

        return obj;
    }   // end decodeObject

    /* ********  I N N E R   C L A S S   I N P U T S T R E A M  ******** */


    /**
     * A InputStream will read data from another
     * {@link java.io.InputStream}, given in the constructor,
     * and encode/decode to/from Base64 notation on the fly.
     *
     * @see Base64
     * @see java.io.FilterInputStream
     * @since 1.3
     */
    public static class InputStream extends java.io.FilterInputStream {
        private int options;        // Options specified
        private boolean encode;         // Encoding or decoding
        private int position;       // Current position in the buffer
        private byte[] buffer;         // Small buffer holding converted data
        private int bufferLength;   // Length of buffer (3 or 4)
        private int numSigBytes;    // Number of meaningful bytes in the buffer
        private int lineLength;
        private boolean breakLines;     // Break lines at less than 80 characters


        /**
         * Constructs a InputStream in DECODE mode.
         *
         * @param in the {@link java.io.InputStream} from which to read data.
         * @since 1.3
         */
        public InputStream(java.io.InputStream in) {
            this(in, DECODE);
        }   // end constructor


        /**
         * Constructs a InputStream in
         * either ENCODE or DECODE mode.
         * <p/>
         * Valid options:<pre>
         *   ENCODE or DECODE: Encode or Decode as data is read.
         *   DONT_BREAK_LINES: don't break lines at 76 characters
         *     (only meaningful when encoding)
         *     <i>Note: Technically, this makes your encoding non-compliant.</i>
         * </pre>
         * <p/>
         * Example: <code>new Base64.InputStream( in, Base64.DECODE )</code>
         *
         * @param in      the {@link java.io.InputStream} from which to read data.
         * @param options Specified options
         * @see Base64#ENCODE
         * @see Base64#DECODE
         * @see Base64#DONT_BREAK_LINES
         * @since 2.0
         */
        public InputStream(java.io.InputStream in, int options) {
            super(in);
            this.options = options;
            this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES;
            this.encode = (options & ENCODE) == ENCODE;
            this.breakLines = breakLines;
            this.encode = encode;
            this.bufferLength = encode ? 4 : 3;
            this.buffer = new byte[bufferLength];
            this.position = -1;
            this.lineLength = 0;
        }   // end constructor

        /**
         * Reads enough of the input stream to convert
         * to/from Base64 and returns the next byte.
         *
         * @return next byte
         * @since 1.3
         */
        public int read() throws java.io.IOException {
            // Do we need to get data?
            if (position < 0) {
                if (encode) {
                    byte[] b3 = new byte[3];
                    int numBinaryBytes = 0;
                    for (int i = 0; i < 3; i++) {
                        try {
                            int b = in.read();

                            // If end of stream, b is -1.
                            if (b >= 0) {
                                b3[i] = (byte)b;
                                numBinaryBytes++;
                            }   // end if: not end of stream

                        }   // end try: read
                        catch (java.io.IOException e) {
                            // Only a problem if we got no data at all.
                            if (i == 0)
                                throw e;

                        }   // end catch
                    }   // end for: each needed input byte

                    if (numBinaryBytes > 0) {
                        encode3to4(b3, 0, numBinaryBytes, buffer, 0);
                        position = 0;
                        numSigBytes = 4;
                    }   // end if: got data
                    else {
                        return -1;
                    }   // end else
                }   // end if: encoding

                // Else decoding
                else {
                    byte[] b4 = new byte[4];
                    int i = 0;
                    for (i = 0; i < 4; i++) {