📄 base64.java
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* @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 != null && bytes.length >= 4 ) { int head = ((int)bytes[0] & 0xff) | ((bytes[1] << 8) & 0xff00); if( 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 ) { 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 /** * Convenience method for encoding data to a file. * * @param dataToEncode byte array of data to encode in base64 form * @param filename Filename for saving encoded data * @return <tt>true</tt> if successful, <tt>false</tt> otherwise * * @since 2.1 */ public static boolean encodeToFile( byte[] dataToEncode, String filename ) { boolean success = false; Base64.OutputStream bos = null; try { bos = new Base64.OutputStream( new java.io.FileOutputStream( filename ), Base64.ENCODE ); bos.write( dataToEncode ); success = true; } // end try catch( java.io.IOException e ) { success = false; } // end catch: IOException finally { try{ bos.close(); } catch( Exception e ){} } // end finally return success; } // end encodeToFile /** * Convenience method for decoding data to a file. * * @param dataToDecode Base64-encoded data as a string * @param filename Filename for saving decoded data * @return <tt>true</tt> if successful, <tt>false</tt> otherwise * * @since 2.1 */ public static boolean decodeToFile( String dataToDecode, String filename ) { boolean success = false; Base64.OutputStream bos = null; try { bos = new Base64.OutputStream( new java.io.FileOutputStream( filename ), Base64.DECODE ); bos.write( dataToDecode.getBytes( PREFERRED_ENCODING ) ); success = true; } // end try catch( java.io.IOException e ) { success = false; } // end catch: IOException finally { try{ bos.close(); } catch( Exception e ){} } // end finally return success; } // end decodeToFile /** * Convenience method for reading a base64-encoded * file and decoding it. * * @param filename Filename for reading encoded data * @return decoded byte array or null if unsuccessful * * @since 2.1 */ public static byte[] decodeFromFile( String filename ) { byte[] decodedData = null; Base64.InputStream bis = null; try { // Set up some useful variables java.io.File file = new java.io.File( filename ); byte[] buffer = null; int length = 0; int numBytes = 0; // Check for size of file if( file.length() > Integer.MAX_VALUE ) { System.err.println( "File is too big for this convenience method (" + file.length() + " bytes)." ); return null; } // end if: file too big for int index buffer = new byte[ (int)file.length() ]; // Open a stream bis = new Base64.InputStream( new java.io.BufferedInputStream( new java.io.FileInputStream( file ) ), Base64.DECODE ); // Read until done while( ( numBytes = bis.read( buffer, length, 4096 ) ) >= 0 ) length += numBytes; // Save in a variable to return decodedData = new byte[ length ]; System.arraycopy( buffer, 0, decodedData, 0, length ); } // end try catch( java.io.IOException e ) { System.err.println( "Error decoding from file " + filename ); } // end catch: IOException finally { try{ bis.close(); } catch( Exception e) {} } // end finally return decodedData; } // end decodeFromFile /** * Convenience method for reading a binary file * and base64-encoding it. * * @param filename Filename for reading binary data * @return base64-encoded string or null if unsuccessful * * @since 2.1 */ public static String encodeFromFile( String filename ) { String encodedData = null; Base64.InputStream bis = null; try { // Set up some useful variables java.io.File file = new java.io.File( filename ); byte[] buffer = new byte[ (int)(file.length() * 1.4) ]; int length = 0; int numBytes = 0; // Open a stream bis = new Base64.InputStream( new java.io.BufferedInputStream( new java.io.FileInputStream( file ) ), Base64.ENCODE ); // Read until done while( ( numBytes = bis.read( buffer, length, 4096 ) ) >= 0 ) length += numBytes; // Save in a variable to return encodedData = new String( buffer, 0, length, Base64.PREFERRED_ENCODING ); } // end try catch( java.io.IOException e ) { System.err.println( "Error encoding from file " + filename ); } // end catch: IOException finally { try{ bis.close(); } catch( Exception e) {} } // end finally return encodedData; } // end encodeFromFile /* ******** 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 * <tt>java.io.InputStream</tt>, given in the constructor, * and encode/decode to/from Base64 notation on the fly. * * @see Base64 * @since 1.3 */ public static class InputStream extends java.io.FilterInputStream { 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 <tt>java.io.InputStream</tt> 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 <tt>java.io.InputStream</tt> 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.breakLines = (options & DONT_BREAK_LINES) != DONT_BREAK_LINES; this.encode = (options & 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;
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