eve.util

Class Base64

java.lang.Object

eve.util.Base64

public class Base64
extends Object

A fast Java class to encode and decode to and from BASE64 in full accordance with RFC 2045.
On Windows XP sp1 with 1.4.2_04 and later ;), this encoder and decoder is about 10 to 30 times faster on small arrays (100 - 1000 bytes) and 2-3 times as fast on larger arrays (100000 - 1000000 bytes).
The encoder produces the same output as the Sun one except that the Sun's encoder appends a trailing line separator if the last character isn't a pad. Unclear why, but it only adds to the length and is probably a side effect. Both are in conformance with RFC 2045 though.

Code used for validation:

                Random rand = new Random();
                // All separators, including the system one.
                String sysSep = System.getProperty("line.separator");
                String[] seps = {null, "", "\r\n", "\n", "\r", sysSep};
                sun.misc.BASE64Encoder sunEnc = new sun.misc.BASE64Encoder();

                for (int i = 0; i < 100000; i++) {
                        byte[] ba1 = new byte[(int) rand.nextInt(100000)];
                        rand.nextBytes(ba1);

                        String sep = seps[rand.nextInt(seps.length)]; // Pick a random separator

                        String s = Base64.encode(ba1, sep);
                        byte[] ba2 = Base64.decode(s);

                        if (Arrays.equals(ba1, ba2) == false) {
                                System.out.println("Integrity Failure!!");
                                System.exit(0);
                        }

                        String sunS = sunEnc.encode(ba1);

                        if (sep != null && sep.equals(sysSep)) {
                                // trim since we aren't handling last separator exactly the same and number of white spaces doesn't matter anyway.
                                if (sunS.trim().equals(s.trim()) == false) {
                                        System.out.println("Sun conformance Failure!!\n\"" + s + "\"\n\n    != \n\n\"" + sunS + "\"");
                                        System.exit(0);
                                }
                        }
                }

                System.out.println("Success!!");
                System.exit(0);
 

Licence: Free to use for any legal purpose, though sending an email to base64 @ miginfocom . com to tell me you're using it will ut a smile on my face! :)
Reprint/republish for public consumption is allowed as long as this licence is included.

Author:

Mikael Grev Date: 2004-aug-02 Time: 11:31:11

Constructor Summary

Constructors

Constructor and Description
Base64()

Method Summary

Modifier and Type	Method and Description
static byte[]	decode(String s) Decodes a BASE64 encoded string.
static String	encode(byte[] bArr, String lineSep) Encodes a raw byte array into a BASE64 string representation i accordance with RFC 2045.

Methods inherited from class java.lang.Object

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

Constructor Detail

Base64

public Base64()

Method Detail

encode

public static final String encode(byte[] bArr,
                                  String lineSep)

Encodes a raw byte array into a BASE64 string representation i accordance with RFC 2045.

Parameters:

bArr - The bytes to convert. If null or length 0, "" will be returned.

lineSep - Optional line separator after 76 characters, unless end of file. Max 2 chars length. If null or length 0 no line breaks will be inserted.
No line separator will be in breach of RFC 2045 which specifies max 76 per line but will be a little faster.

Returns:

A BASE64 encoded string. Never null.

decode

public static final byte[] decode(String s)

Decodes a BASE64 encoded string. All illegal characters will be igored and can handle both strings with and without line separators.

Parameters:

s - The string. null or "" will return an empty array.

Returns:

The decoded array of bytes. Never null but may be of length 0.