/**
* Encodes and decodes to and from Base64 notation.
*
* <p>
* Change Log:
* </p>
* <ul>
* <li>v2.0 - I got rid of methods that used booleans to set options.
* Now everything is more consolidated and cleaner. The code now detects
* when data that's being decoded is gzip-compressed and will decompress it
* automatically. Generally things are cleaner. You'll probably have to
* change some method calls that you were making to support the new
* options format (<tt>int</tt>s that you "OR" together).</li>
* <li>v1.5.1 - Fixed bug when decompressing and decoding to a
* byte[] using <tt>decode( String s, boolean gzipCompressed )</tt>.
* Added the ability to "suspend" encoding in the Output Stream so
* you can turn on and off the encoding if you need to embed base64
* data in an otherwise "normal" stream (like an XML file).</li>
* <li>v1.5 - Output stream pases on flush() command but doesn't do anything itself.
* This helps when using GZIP streams.
* Added the ability to GZip-compress objects before encoding them.</li>
* <li>v1.4 - Added helper methods to read/write files.</li>
* <li>v1.3.6 - Fixed OutputStream.flush() so that 'position' is reset.</li>
* <li>v1.3.5 - Added flag to turn on and off line breaks. Fixed bug in input stream
* where last buffer being read, if not completely full, was not returned.</li>
* <li>v1.3.4 - Fixed when "improperly padded stream" error was thrown at the wrong time.</li>
* <li>v1.3.3 - Fixed I/O streams which were totally messed up.</li>
* </ul>
*
* <p>
* I am placing this code in the Public Domain. Do with it as you will.
* This software comes with no guarantees or warranties but with
* plenty of well-wishing instead!
* Please visit <a href="http://iharder.net/xmlizable">http://iharder.net/base64</a>
* periodically to check for updates or to contribute improvements.
* </p>
*
* @author Robert Harder
* @author rob@iharder.net
* @version 2.0
*/
package net.sourceforge.pain.util;
public class Base64 {
/* ******** P U B L I C F I E L D S ******** */
/** No options specified. Value is zero. */
public final static int NO_OPTIONS = 0;
/** Specify encoding. */
public final static int ENCODE = 1;
/** Specify decoding. */
public final static int DECODE = 0;
/** Specify that data should be gzip-compressed. */
public final static int GZIP = 2;
/** Don't break lines when encoding (violates strict Base64 specification) */
public final static int DONT_BREAK_LINES = 8;
/* ******** P R I V A T E F I E L D S ******** */
/** Maximum line length (76) of Base64 output. */
private final static int MAX_LINE_LENGTH = 76;
/** The equals sign (=) as a byte. */
private final static byte EQUALS_SIGN = (byte) '=';
/** The new line character (\n) as a byte. */
private final static byte NEW_LINE = (byte) '\n';
/** The 64 valid Base64 values. */
private final static byte[] ALPHABET =
{
(byte) 'A', (byte) 'B', (byte) 'C', (byte) 'D', (byte) 'E', (byte) 'F', (byte) 'G',
(byte) 'H', (byte) 'I', (byte) 'J', (byte) 'K', (byte) 'L', (byte) 'M', (byte) 'N',
(byte) 'O', (byte) 'P', (byte) 'Q', (byte) 'R', (byte) 'S', (byte) 'T', (byte) 'U',
(byte) 'V', (byte) 'W', (byte) 'X', (byte) 'Y', (byte) 'Z',
(byte) 'a', (byte) 'b', (byte) 'c', (byte) 'd', (byte) 'e', (byte) 'f', (byte) 'g',
(byte) 'h', (byte) 'i', (byte) 'j', (byte) 'k', (byte) 'l', (byte) 'm', (byte) 'n',
(byte) 'o', (byte) 'p', (byte) 'q', (byte) 'r', (byte) 's', (byte) 't', (byte) 'u',
(byte) 'v', (byte) 'w', (byte) 'x', (byte) 'y', (byte) 'z',
(byte) '0', (byte) '1', (byte) '2', (byte) '3', (byte) '4', (byte) '5',
(byte) '6', (byte) '7', (byte) '8', (byte) '9', (byte) '+', (byte) '/'
};
/**
* Translates a Base64 value to either its 6-bit reconstruction value
* or a negative number indicating some other meaning.
**/
private final static byte[] DECODABET =
{
-9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 0 - 8
-5, -5, // Whitespace: Tab and Linefeed
-9, -9, // Decimal 11 - 12
-5, // Whitespace: Carriage Return
-9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 14 - 26
-9, -9, -9, -9, -9, // Decimal 27 - 31
-5, // Whitespace: Space
-9, -9, -9, -9, -9, -9, -9, -9, -9, -9, // Decimal 33 - 42
62, // Plus sign at decimal 43
-9, -9, -9, // Decimal 44 - 46
63, // Slash at decimal 47
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, // Numbers zero through nine
-9, -9, -9, // Decimal 58 - 60
-1, // Equals sign at decimal 61
-9, -9, -9, // Decimal 62 - 64
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, // Letters 'A' through 'N'
14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // Letters 'O' through 'Z'
-9, -9, -9, -9, -9, -9, // Decimal 91 - 96
26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, // Letters 'a' through 'm'
39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, // Letters 'n' through 'z'
-9, -9, -9, -9 // Decimal 123 - 126
/*,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 127 - 139
-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 140 - 152
-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 153 - 165
-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 166 - 178
-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 179 - 191
-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 192 - 204
-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 205 - 217
-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 218 - 230
-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9, // Decimal 231 - 243
-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9,-9 // Decimal 244 - 255 */
};
// private final static byte BAD_ENCODING = -9; // Indicates error in encoding
private final static byte WHITE_SPACE_ENC = -5; // Indicates white space in encoding
private final static byte EQUALS_SIGN_ENC = -1; // Indicates equals sign in encoding
/** Defeats instantiation. */
private Base64() {
}
/* ******** E N C O D I N G M E T H O D S ******** */
/**
* Encodes the first three bytes of array <var>threeBytes</var>
* and returns a four-byte array in Base64 notation.
*
* @param threeBytes the array to convert
* @return four byte array in Base64 notation.
* @since 1.3
*/
// private static byte[] encode3to4(byte[] threeBytes) {
// return encode3to4(threeBytes, 3);
// } // end encodeToBytes
/**
* Encodes up to the first three bytes of array <var>threeBytes</var>
* and returns a four-byte array in Base64 notation.
* The actual number of significant bytes in your array is
* given by <var>numSigBytes</var>.
* The array <var>threeBytes</var> needs only be as big as
* <var>numSigBytes</var>.
*
* @param threeBytes the array to convert
* @param numSigBytes the number of significant bytes in your array
* @return four byte array in Base64 notation.
* @since 1.3
*/
// private static byte[] encode3to4(byte[] threeBytes, int numSigBytes) {
// byte[] dest = new byte[4];
// encode3to4(threeBytes, 0, numSigBytes, dest, 0);
// return dest;
// }
/**
* Encodes up to the first three bytes of array <var>threeBytes</var>
* and returns a four-byte array in Base64 notation.
* The actual number of significant bytes in your array is
* given by <var>numSigBytes</var>.
* The array <var>threeBytes</var> needs only be as big as
* <var>numSigBytes</var>.
* Code can reuse a byte array by passing a four-byte array as <var>b4</var>.
*
* @param b4 A reusable byte array to reduce array instantiation
* @param threeBytes the array to convert
* @param numSigBytes the number of significant bytes in your array
* @return four byte array in Base64 notation.
* @since 1.5.1
*/
private static byte[] encode3to4(byte[] b4, byte[] threeBytes, int numSigBytes) {
encode3to4(threeBytes, 0, numSigBytes, b4, 0);
return b4;
} // end encode3to4
/**
* Encodes up to three bytes of the array <var>source</var>
* and writes the resulting four Base64 bytes to <var>destination</var>.
* The source and destination arrays can be manipulated
* anywhere along their length by specifying
* <var>srcOffset</var> and <var>destOffset</var>.
* This method does not check to make sure your arrays
* are large enough to accomodate <var>srcOffset</var> + 3 for
* the <var>source</var> array or <var>destOffset</var> + 4 for
* the <var>destination</var> array.
* The actual number of significant bytes in your array is
* given by <var>numSigBytes</var>.
*
* @param source the array to convert
* @param srcOffset the index where conversion begins
* @param numSigBytes the number of significant bytes in your array
* @param destination the array to hold the conversion
* @param destOffset the index where output will be put
* @return the <var>destination</var> array
* @since 1.3
*/
private static byte[] encode3to4(
byte[] source, int srcOffset, int numSigBytes,
byte[] destination, int destOffset) {
// 1 2 3
// 01234567890123456789012345678901 Bit position
// --------000000001111111122222222 Array position from threeBytes
// --------| || || || | Six bit groups to index ALPHABET
// >>18 >>12 >> 6 >> 0 Right shift necessary
// 0x3f 0x3f 0x3f Additional AND
// Create buffer with zero-padding if there are only one or two
// significant bytes passed in the array.
// We have to shift left 24 in order to flush out the 1's that appear
// when Java treats a value as negative that is cast from a byte to an int.
int inBuff = (numSigBytes > 0 ? ((source[srcOffset] << 24) >>> 8) : 0)
| (numSigBytes > 1 ? ((source[srcOffset + 1] << 24) >>> 16) : 0)
| (numSigBytes > 2 ? ((source[srcOffset + 2] << 24) >>> 24) : 0);
switch (numSigBytes) {
case 3:
destination[destOffset] = ALPHABET[(inBuff >>> 18)];
destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
destination[destOffset + 3] = ALPHABET[(inBuff) & 0x3f];
return destination;
case 2:
destination[destOffset] = ALPHABET[(inBuff >>> 18)];
destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
destination[destOffset + 2] = ALPHABET[(inBuff >>> 6) & 0x3f];
destination[destOffset + 3] = EQUALS_SIGN;
return destination;
case 1:
destination[destOffset] = ALPHABET[(inBuff >>> 18)];
destination[destOffset + 1] = ALPHABET[(inBuff >>> 12) & 0x3f];
destination[destOffset + 2] = EQUALS_SIGN;
destination[destOffset + 3] = EQUALS_SIGN;
return destination;
default:
return destination;
} // end switch
} // end encode3to4
/**
* Serializes an object and returns the Base64-encoded
* version of that serialized object. If the object
* cannot be serialized or there is another error,
* the method will return <tt>null</tt>.
* The object is not GZip-compressed before being encoded.
*
* @param serializableObject The object to encode
* @return The Base64-encoded object
* @since 1.4
*/
public static String encodeObject(java.io.Serializable serializableObject) {
return encodeObject(serializableObject, NO_OPTIONS);
} // end encodeObject
/**
* Serializes an object and returns the Base64-encoded
* version of that serialized object. If the object
* cannot be serialized or there is another error,
* the method will return <tt>null</tt>.
* <p>
* Valid options:<pre>
* GZIP: gzip-compresses object before encoding it.
* DONT_BREAK_LINES: don't break lines at 76 characters
* <i>Note: Technically, this makes your encoding non-compliant.</i>
* </pre>
* <p>
* Example: <code>encodeObject( myObj, Base64.GZIP )</code> or
* <p>
* Example: <code>encodeObject( myObj, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
*
* @param serializableObject The object to encode
* @param options Specified options
* @return The Base64-encoded object
* @see Base64#GZIP
* @see Base64#DONT_BREAK_LINES
* @since 2.0
*/
public static String encodeObject(java.io.Serializable serializableObject, int options) {
// Streams
java.io.ByteArrayOutputStream baos = null;
java.io.OutputStream b64os = null;
java.io.ObjectOutputStream oos = null;
java.util.zip.GZIPOutputStream gzos = null;
// Isolate options
int gzip = (options & GZIP);
int dontBreakLines = (options & DONT_BREAK_LINES);
try {
// ObjectOutputStream -> (GZIP) -> Base64 -> ByteArrayOutputStream
baos = new java.io.ByteArrayOutputStream();
b64os = new Base64.OutputStream(baos, ENCODE | dontBreakLines);
// GZip?
if (gzip == GZIP) {
gzos = new java.util.zip.GZIPOutputStream(b64os);
oos = new java.io.ObjectOutputStream(gzos);
} // end if: gzip
else
oos = new java.io.ObjectOutputStream(b64os);
oos.writeObject(serializableObject);
return new String(baos.toByteArray());
} // end try
catch (java.io.IOException e) {
e.printStackTrace();
return null;
} // end catch
finally {
try {
if (oos != null) {
oos.close();
}
} catch (Exception e) {
}
try {
if (gzos != null) {
gzos.close();
}
} catch (Exception e) {
}
try {
b64os.close();
} catch (Exception e) {
}
try {
baos.close();
} catch (Exception e) {
}
} // end finally
} // end encode
/**
* Encodes a byte array into Base64 notation.
* Does not GZip-compress data.
*
* @param source The data to convert
* @since 1.4
*/
public static String encodeBytes(byte[] source) {
return encodeBytes(source, 0, source.length, NO_OPTIONS);
} // end encodeBytes
/**
* Encodes a byte array into Base64 notation.
* <p>
* Valid options:<pre>
* GZIP: gzip-compresses object before encoding it.
* DONT_BREAK_LINES: don't break lines at 76 characters
* <i>Note: Technically, this makes your encoding non-compliant.</i>
* </pre>
* <p>
* Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
* <p>
* Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
*
*
* @param source The data to convert
* @param options Specified options
* @see Base64#GZIP
* @see Base64#DONT_BREAK_LINES
* @since 2.0
*/
public static String encodeBytes(byte[] source, int options) {
return encodeBytes(source, 0, source.length, options);
} // end encodeBytes
/**
* Encodes a byte array into Base64 notation.
* Does not GZip-compress data.
*
* @param source The data to convert
* @param off Offset in array where conversion should begin
* @param len Length of data to convert
* @since 1.4
*/
public static String encodeBytes(byte[] source, int off, int len) {
return encodeBytes(source, off, len, NO_OPTIONS);
} // end encodeBytes
/**
* Encodes a byte array into Base64 notation.
* <p>
* Valid options:<pre>
* GZIP: gzip-compresses object before encoding it.
* DONT_BREAK_LINES: don't break lines at 76 characters
* <i>Note: Technically, this makes your encoding non-compliant.</i>
* </pre>
* <p>
* Example: <code>encodeBytes( myData, Base64.GZIP )</code> or
* <p>
* Example: <code>encodeBytes( myData, Base64.GZIP | Base64.DONT_BREAK_LINES )</code>
*
*
* @param source The data to convert
* @param off Offset in array where conversion should begin
* @param len Length of data to convert
* @param options Specified options
* @see Base64#GZIP
* @see Base64#DONT_BREAK_LINES
* @since 2.0
*/
public static String encodeBytes(byte[] source, int off, int len, int options) {
// Isolate options
int dontBreakLines = (options & DONT_BREAK_LINES);
int gzip = (options & GZIP);
// Compress?
if (gzip == GZIP) {
java.io.ByteArrayOutputStream baos = null;
java.util.zip.GZIPOutputStream gzos = null;
Base64.OutputStream b64os = null;
try {
// GZip -> Base64 -> ByteArray
baos = new java.io.ByteArrayOutputStream();
b64os = new Base64.OutputStream(baos, ENCODE | dontBreakLines);
gzos = new java.util.zip.GZIPOutputStream(b64os);
gzos.write(source, off, len);
gzos.close();
} // end try
catch (java.io.IOException e) {
e.printStackTrace();
return null;
} // end catch
finally {
try {
gzos.close();
} catch (Exception e) {
}
try {
b64os.close();
} catch (Exception e) {
}
try {
baos.close();
} catch (Exception e) {
}
} // end finally
return new String(baos.toByteArray());
} // end if: compress
// Else, don't compress. Better not to use streams at all then.
else {
// Convert option to boolean in way that code likes it.
boolean breakLines = dontBreakLines == 0;
int len43 = len * 4 / 3;
byte[] outBuff = new byte[(len43) // Main 4:3
+ ((len % 3) > 0 ? 4 : 0) // Account for padding
+ (breakLines ? (len43 / MAX_LINE_LENGTH) : 0)]; // New lines
int d = 0;
int e = 0;
int len2 = len - 2;
int lineLength = 0;
for (; d < len2; d += 3, e += 4) {
encode3to4(source, d + off, 3, outBuff, e);
lineLength += 4;
if (breakLines && lineLength == MAX_LINE_LENGTH) {
outBuff[e + 4] = NEW_LINE;
e++;
lineLength = 0;
} // end if: end of line
} // en dfor: each piece of array
if (d < len) {
encode3to4(source, d + off, len - d, outBuff, e);
e += 4;
} // end if: some padding needed
return new String(outBuff, 0, e);
} // end else: don't compress
} // end encodeBytes
/* ******** D E C O D I N G M E T H O D S ******** */
/**
* Decodes the first four bytes of array <var>fourBytes</var>
* and returns an array up to three bytes long with the
* decoded values.
*
* @param fourBytes the array with Base64 content
* @return array with decoded values
* @since 1.3
*/
// private static byte[] decode4to3(byte[] fourBytes) {
// byte[] outBuff1 = new byte[3];
// int count = decode4to3(fourBytes, 0, outBuff1, 0);
// byte[] outBuff2 = new byte[count];
//
// for (int i = 0; i < count; i++) {
// outBuff2[i] = outBuff1[i];
// }
//
// return outBuff2;
// }
/**
* Decodes four bytes from array <var>source</var>
* and writes the resulting bytes (up to three of them)
* to <var>destination</var>.
* The source and destination arrays can be manipulated
* anywhere along their length by specifying
* <var>srcOffset</var> and <var>destOffset</var>.
* This method does not check to make sure your arrays
* are large enough to accomodate <var>srcOffset</var> + 4 for
* the <var>source</var> array or <var>destOffset</var> + 3 for
* the <var>destination</var> array.
* This method returns the actual number of bytes that
* were converted from the Base64 encoding.
*
*
* @param source the array to convert
* @param srcOffset the index where conversion begins
* @param destination the array to hold the conversion
* @param destOffset the index where output will be put
* @return the number of decoded bytes converted
* @since 1.3
*/
private static int decode4to3(byte[] source, int srcOffset, byte[] destination, int destOffset) {
// Example: Dk==
if (source[srcOffset + 2] == EQUALS_SIGN) {
// Two ways to do the same thing. Don't know which way I like best.
//int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
// | ( ( DECODABET[ source[ srcOffset + 1] ] << 24 ) >>> 12 );
int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
| ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12);
destination[destOffset] = (byte) (outBuff >>> 16);
return 1;
}
// Example: DkL=
else if (source[srcOffset + 3] == EQUALS_SIGN) {
// Two ways to do the same thing. Don't know which way I like best.
//int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
// | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
// | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 );
int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
| ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
| ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6);
destination[destOffset] = (byte) (outBuff >>> 16);
destination[destOffset + 1] = (byte) (outBuff >>> 8);
return 2;
}
// Example: DkLE
else {
try {
// Two ways to do the same thing. Don't know which way I like best.
//int outBuff = ( ( DECODABET[ source[ srcOffset ] ] << 24 ) >>> 6 )
// | ( ( DECODABET[ source[ srcOffset + 1 ] ] << 24 ) >>> 12 )
// | ( ( DECODABET[ source[ srcOffset + 2 ] ] << 24 ) >>> 18 )
// | ( ( DECODABET[ source[ srcOffset + 3 ] ] << 24 ) >>> 24 );
int outBuff = ((DECODABET[source[srcOffset]] & 0xFF) << 18)
| ((DECODABET[source[srcOffset + 1]] & 0xFF) << 12)
| ((DECODABET[source[srcOffset + 2]] & 0xFF) << 6)
| ((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;
byte sbiCrop;
byte sbiDecode;
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 = s.getBytes();
bytes = decode(bytes, 0, bytes.length);
// Check to see if it's gzip-compressed
// GZIP Magic Two-Byte Number: 0x8b1f (35615)
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;
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
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) {
e.printStackTrace();
obj = null;
} // end catch
catch (java.lang.ClassNotFoundException e) {
e.printStackTrace();
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 {@link Base64.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 {@link Base64.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 {@link Base64.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;
for (i = 0; i < 4; i++) {
// Read four "meaningful" bytes:
int b;
do {
b = in.read();
} while (b >= 0 && DECODABET[b & 0x7f] <= WHITE_SPACE_ENC);
if (b < 0)
break; // Reads a -1 if end of stream
b4[i] = (byte) b;
} // end for: each needed input byte
if (i == 4) {
numSigBytes = decode4to3(b4, 0, buffer, 0);
position = 0;
} // end if: got four characters
else if (i == 0) {
return -1;
} // end else if: also padded correctly
else {
// Must have broken out from above.
throw new java.io.IOException("Improperly padded Base64 input.");
} // end
} // end else: decode
} // end else: get data
// Got data?
if (position >= 0) {
// End of relevant data?
if (/*!encode &&*/ position >= numSigBytes) {
return -1;
}
if (encode && breakLines && lineLength >= MAX_LINE_LENGTH) {
lineLength = 0;
return '\n';
} // end if
else {
lineLength++; // This isn't important when decoding
// but throwing an extra "if" seems
// just as wasteful.
int b = buffer[position++];
if (position >= bufferLength) {
position = -1;
}
return b & 0xFF; // This is how you "cast" a byte that's
// intended to be unsigned.
} // end else
} // end if: position >= 0
// Else error
else {
// When JDK1.4 is more accepted, use an assertion here.
throw new java.io.IOException("Error in Base64 code reading stream.");
} // end else
} // end read
/**
* Calls {@link #read} repeatedly until the end of stream
* is reached or <var>len</var> bytes are read.
* Returns number of bytes read into array or -1 if
* end of stream is encountered.
*
* @param dest array to hold values
* @param off offset for array
* @param len max number of bytes to read into array
* @return bytes read into array or -1 if end of stream is encountered.
* @since 1.3
*/
public int read(byte[] dest, int off, int len) throws java.io.IOException {
int i;
int b;
for (i = 0; i < len; i++) {
b = read();
//if( b < 0 && i == 0 )
// return -1;
if (b >= 0) {
dest[off + i] = (byte) b;
} else if (i == 0) {
return -1;
} else
break; // Out of 'for' loop
} // end for: each byte read
return i;
} // end read
} // end inner class InputStream
/* ******** I N N E R C L A S S O U T P U T S T R E A M ******** */
/**
* A {@link Base64.OutputStream} will write data to another
* {@link java.io.OutputStream}, given in the constructor,
* and encode/decode to/from Base64 notation on the fly.
*
* @see Base64
* @see java.io.FilterOutputStream
* @since 1.3
*/
public static class OutputStream extends java.io.FilterOutputStream {
private int options;
private boolean encode;
private int position;
private byte[] buffer;
private int bufferLength;
private int lineLength;
private boolean breakLines;
private byte[] b4; // Scratch used in a few places
private boolean suspendEncoding;
/**
* Constructs a {@link Base64.OutputStream} in ENCODE mode.
*
* @param out the {@link java.io.OutputStream} to which data will be written.
* @since 1.3
*/
public OutputStream(java.io.OutputStream out) {
this(out, ENCODE);
} // end constructor
/**
* Constructs a {@link Base64.OutputStream} 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.OutputStream( out, Base64.ENCODE )</code>
*
* @param out the {@link java.io.OutputStream} to which data will be written.
* @param options Specified options.
* @see Base64#ENCODE
* @see Base64#DECODE
* @see Base64#DONT_BREAK_LINES
* @since 1.3
*/
public OutputStream(java.io.OutputStream out, int options) {
super(out);
this.options = options;
this.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES;
this.encode = (options & ENCODE) == ENCODE;
this.bufferLength = encode ? 3 : 4;
this.buffer = new byte[bufferLength];
this.position = 0;
this.lineLength = 0;
this.suspendEncoding = false;
this.b4 = new byte[4];
} // end constructor
/**
* Writes the byte to the output stream after
* converting to/from Base64 notation.
* When encoding, bytes are buffered three
* at a time before the output stream actually
* gets a write() call.
* When decoding, bytes are buffered four
* at a time.
*
* @param theByte the byte to write
* @since 1.3
*/
public void write(int theByte) throws java.io.IOException {
// Encoding suspended?
if (suspendEncoding) {
super.out.write(theByte);
return;
} // end if: supsended
// Encode?
if (encode) {
buffer[position++] = (byte) theByte;
if (position >= bufferLength) // Enough to encode.
{
out.write(encode3to4(b4, buffer, bufferLength));
lineLength += 4;
if (breakLines && lineLength >= MAX_LINE_LENGTH) {
out.write(NEW_LINE);
lineLength = 0;
} // end if: end of line
position = 0;
} // end if: enough to output
} // end if: encoding
// Else, Decoding
else {
// Meaningful Base64 character?
if (DECODABET[theByte & 0x7f] > WHITE_SPACE_ENC) {
buffer[position++] = (byte) theByte;
if (position >= bufferLength) // Enough to output.
{
int len = Base64.decode4to3(buffer, 0, b4, 0);
out.write(b4, 0, len);
//out.write( Base64.decode4to3( buffer ) );
position = 0;
} // end if: enough to output
} // end if: meaningful base64 character
else if (DECODABET[theByte & 0x7f] != WHITE_SPACE_ENC) {
throw new java.io.IOException("Invalid character in Base64 data.");
} // end else: not white space either
} // end else: decoding
} // end write
/**
* Calls {@link #write} repeatedly until <var>len</var>
* bytes are written.
*
* @param theBytes array from which to read bytes
* @param off offset for array
* @param len max number of bytes to read into array
* @since 1.3
*/
public void write(byte[] theBytes, int off, int len) throws java.io.IOException {
// Encoding suspended?
if (suspendEncoding) {
super.out.write(theBytes, off, len);
return;
} // end if: supsended
for (int i = 0; i < len; i++) {
write(theBytes[off + i]);
} // end for: each byte written
} // end write
/**
* Method added by PHIL. [Thanks, PHIL. -Rob]
* This pads the buffer without closing the stream.
*/
public void flushBase64() throws java.io.IOException {
if (position > 0) {
if (encode) {
out.write(encode3to4(b4, buffer, position));
position = 0;
} // end if: encoding
else {
throw new java.io.IOException("Base64 input not properly padded.");
} // end else: decoding
} // end if: buffer partially full
} // end flush
/**
* Flushes and closes (I think, in the superclass) the stream.
*
* @since 1.3
*/
public void close() throws java.io.IOException {
// 1. Ensure that pending characters are written
flushBase64();
// 2. Actually close the stream
// Base class both flushes and closes.
super.close();
buffer = null;
out = null;
} // end close
/**
* Suspends encoding of the stream.
* May be helpful if you need to embed a piece of
* base640-encoded data in a stream.
*
* @since 1.5.1
*/
public void suspendEncoding() throws java.io.IOException {
flushBase64();
this.suspendEncoding = true;
} // end suspendEncoding
/**
* Resumes encoding of the stream.
* May be helpful if you need to embed a piece of
* base640-encoded data in a stream.
*
* @since 1.5.1
*/
public void resumeEncoding() {
this.suspendEncoding = false;
} // end resumeEncoding
} // end inner class OutputStream
} // end class Base64
