public class Base64
extends java.lang.Object
This code is a stripped down version of Robert Harder's Public Domain Base64 implementation. GZIP support, InputStream and OutputStream stuff and some unneeded encode/decode methods have been removed.
-- Original comments follow --
Encodes and decodes to and from Base64 notation.
Change Log:
int
s
that you "OR" together).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).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.
Modifier and Type | Field and Description |
---|---|
private static byte[] |
_NATIVE_ALPHABET |
private static byte[] |
ALPHABET
The 64 valid Base64 values.
|
private static byte[] |
DECODABET
Translates a Base64 value to either its 6-bit reconstruction value or a negative number
indicating some other meaning.
|
static int |
DECODE
Specify decoding.
|
static int |
DONT_BREAK_LINES
Don't break lines when encoding (violates strict Base64 specification).
|
static int |
ENCODE
Specify encoding.
|
private static byte |
EQUALS_SIGN
The equals sign (=) as a byte.
|
private static byte |
EQUALS_SIGN_ENC |
private static int |
MAX_LINE_LENGTH
Maximum line length (76) of Base64 output.
|
private static byte |
NEW_LINE
The new line character (\n) as a byte.
|
static int |
NO_OPTIONS
No options specified.
|
private static java.lang.String |
PREFERRED_ENCODING
Preferred encoding.
|
private static byte |
WHITE_SPACE_ENC |
Modifier | Constructor and Description |
---|---|
private |
Base64()
Defeats instantiation.
|
Modifier and Type | Method and Description |
---|---|
static byte[] |
decode(byte[] source,
int off,
int len)
Very low-level access to decoding ASCII characters in the form of a byte array.
|
static byte[] |
decode(java.lang.String s)
Decodes data from Base64 notation, automatically detecting gzip-compressed data and
decompressing it.
|
private static int |
decode4to3(byte[] source,
int srcOffset,
byte[] destination,
int destOffset)
Decodes four bytes from array source and writes the resulting bytes (up to three of
them) to destination.
|
private static byte[] |
encode3to4(byte[] source,
int srcOffset,
int numSigBytes,
byte[] destination,
int destOffset)
Encodes up to three bytes of the array source and writes the resulting four Base64
bytes to destination.
|
static java.lang.String |
encodeBytes(byte[] source)
Encodes a byte array into Base64 notation.
|
static java.lang.String |
encodeBytes(byte[] source,
int options)
Encodes a byte array into Base64 notation.
|
static java.lang.String |
encodeBytes(byte[] source,
int off,
int len)
Encodes a byte array into Base64 notation.
|
static java.lang.String |
encodeBytes(byte[] source,
int off,
int len,
int options)
Encodes a byte array into Base64 notation.
|
public static final int NO_OPTIONS
public static final int ENCODE
public static final int DECODE
public static final int DONT_BREAK_LINES
private static final int MAX_LINE_LENGTH
private static final byte EQUALS_SIGN
private static final byte NEW_LINE
private static final java.lang.String PREFERRED_ENCODING
private static final byte[] ALPHABET
private static final byte[] _NATIVE_ALPHABET
private static final byte[] DECODABET
private static final byte WHITE_SPACE_ENC
private static final byte EQUALS_SIGN_ENC
private static byte[] encode3to4(byte[] source, int srcOffset, int numSigBytes, byte[] destination, int destOffset)
source
- the array to convertsrcOffset
- the index where conversion beginsnumSigBytes
- the number of significant bytes in your arraydestination
- the array to hold the conversiondestOffset
- the index where output will be putpublic static java.lang.String encodeBytes(byte[] source)
source
- The data to convertpublic static java.lang.String encodeBytes(byte[] source, int options)
Encodes a byte array into Base64 notation.
Valid options:
GZIP: gzip-compresses object before encoding it. DONT_BREAK_LINES: don't break lines at 76 characters Note: Technically, this makes your encoding non-compliant.
Example: encodeBytes( myData, Base64.GZIP )
or
Example: encodeBytes(
myData, Base64.GZIP | Base64.DONT_BREAK_LINES )
source
- The data to convertoptions
- Specified optionsDONT_BREAK_LINES
public static java.lang.String encodeBytes(byte[] source, int off, int len)
source
- The data to convertoff
- Offset in array where conversion should beginlen
- Length of data to convertpublic static java.lang.String encodeBytes(byte[] source, int off, int len, int options)
Encodes a byte array into Base64 notation.
Valid options:
GZIP: gzip-compresses object before encoding it. DONT_BREAK_LINES: don't break lines at 76 characters Note: Technically, this makes your encoding non-compliant.
Example: encodeBytes( myData, Base64.GZIP )
or
Example: encodeBytes(
myData, Base64.GZIP | Base64.DONT_BREAK_LINES )
source
- The data to convertoff
- Offset in array where conversion should beginlen
- Length of data to convertoptions
- Specified optionsDONT_BREAK_LINES
private static int decode4to3(byte[] source, int srcOffset, byte[] destination, int destOffset)
source
- the array to convertsrcOffset
- the index where conversion beginsdestination
- the array to hold the conversiondestOffset
- the index where output will be putpublic static byte[] decode(byte[] source, int off, int len)
source
- The Base64 encoded dataoff
- The offset of where to begin decodinglen
- The length of characters to decodepublic static byte[] decode(java.lang.String s)
s
- the string to decode