com.metamatrix.core.util
Class Base64

java.lang.Object
  com.metamatrix.core.util.Base64

public class Base64
extends java.lang.Object

Encodes and decodes to and from Base64 notation.

Homepage: http://iharder.net/base64.

The options parameter, which appears in a few places, is used to pass several pieces of information to the encoder. In the "higher level" methods such as encodeBytes( bytes, options ) the options parameter can be used to indicate such things as first gzipping the bytes before encoding them, not inserting linefeeds (though that breaks strict Base64 compatibility), and encoding using the URL-safe and Ordered dialects.

The constants defined in Base64 can be OR-ed together to combine options, so you might make a call like this:

String encoded = Base64.encodeBytes( mybytes, Base64.GZIP | Base64.DONT_BREAK_LINES );

to compress the data before encoding it and then making the output have no newline characters.

Change Log:

• v2.2.2 - Fixed encodeFileToFile and decodeFileToFile to use the Base64.InputStream class to encode and decode on the fly which uses less memory than encoding/decoding an entire file into memory before writing.
• v2.2.1 - Fixed bug using URL_SAFE and ORDERED encodings. Fixed bug when using very small files (~< 40 bytes).
• v2.2 - Added some helper methods for encoding/decoding directly from one file to the next. Also added a main() method to support command line encoding/decoding from one file to the next. Also added these Base64 dialects:
  1. The default is RFC3548 format.
  2. Calling Base64.setFormat(Base64.BASE64_FORMAT.URLSAFE_FORMAT) generates URL and file name friendly format as described in Section 4 of RFC3548. http://www.faqs.org/rfcs/rfc3548.html
  3. Calling Base64.setFormat(Base64.BASE64_FORMAT.ORDERED_FORMAT) generates URL and file name friendly format that preserves lexical ordering as described in http://www.faqs.org/qa/rfcc-1940.html
  Special thanks to Jim Kellerman at http://www.powerset.com/ for contributing the new Base64 dialects.
• v2.1 - Cleaned up javadoc comments and unused variables and methods. Added some convenience methods for reading and writing to and from files.
• v2.0.2 - Now specifies UTF-8 encoding in places where the code fails on systems with other encodings (like EBCDIC).
• v2.0.1 - Fixed an error when decoding a single byte, that is, when the encoded data was a single byte.
• 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 (ints that you "OR" together).
• v1.5.1 - Fixed bug when decompressing and decoding to a byte[] using decode( String s, boolean gzipCompressed ). 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).
• 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.
• v1.4 - Added helper methods to read/write files.
• v1.3.6 - Fixed OutputStream.flush() so that 'position' is reset.
• 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.
• v1.3.4 - Fixed when "improperly padded stream" error was thrown at the wrong time.
• v1.3.3 - Fixed I/O streams which were totally messed up.

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 http://iharder.net/base64 periodically to check for updates or to contribute improvements.

Version:

2.2.2

Author:

Robert Harder, rob@iharder.net

Method Summary

static byte[]	decode(java.lang.String s) Decodes data from Base64 notation.
static java.lang.String	encodeBytes(byte[] source) Encodes a byte array into Base64 notation.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

encodeBytes

public static java.lang.String encodeBytes(byte[] source)

Encodes a byte array into Base64 notation. Does not GZip-compress data.

Parameters:

source - The data to convert

Since:

1.4

decode

public static byte[] decode(java.lang.String s)

Decodes data from Base64 notation.

Parameters:

s - the string to decode

Returns:

the decoded data

Since:

1.4