public class Base64 extends Object
Encodes and decodes to and from Base64 notation.
Homepage: http://iharder.net/base64.
Change Log:
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 | Class and Description |
---|---|
static class |
Base64.InputStream
A
Base64.InputStream will read data from another
java.io.InputStream, given in the constructor,
and encode/decode to/from Base64 notation on the fly. |
static class |
Base64.OutputStream
A
Base64.OutputStream will write data to another
java.io.OutputStream, given in the constructor,
and encode/decode to/from Base64 notation on the fly. |
Modifier and Type | Field and Description |
---|---|
private static byte[] |
_ORDERED_ALPHABET
I don't get the point of this technique, but it is described here:
http://www.faqs.org/qa/rfcc-1940.html.
|
private static byte[] |
_ORDERED_DECODABET
Used in decoding the "ordered" dialect of Base64.
|
private static byte[] |
_STANDARD_ALPHABET
The 64 valid Base64 values.
|
private static byte[] |
_STANDARD_DECODABET
Translates a Base64 value to either its 6-bit reconstruction value
or a negative number indicating some other meaning.
|
private static byte[] |
_URL_SAFE_ALPHABET
Used in the URL- and Filename-safe dialect described in Section 4 of RFC3548:
http://www.faqs.org/rfcs/rfc3548.html.
|
private static byte[] |
_URL_SAFE_DECODABET
Used in decoding URL- and Filename-safe dialects of Base64.
|
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 |
static int |
GZIP
Specify that data should be gzip-compressed.
|
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.
|
static int |
ORDERED
Encode using the special "ordered" dialect of Base64 described here:
http://www.faqs.org/qa/rfcc-1940.html.
|
private static String |
PREFERRED_ENCODING
Preferred encoding.
|
static int |
URL_SAFE
Encode using Base64-like encoding that is URL- and Filename-safe as described
in Section 4 of RFC3548:
http://www.faqs.org/rfcs/rfc3548.html.
|
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,
int options)
Very low-level access to decoding ASCII characters in
the form of a byte array.
|
static byte[] |
decode(String s)
Decodes data from Base64 notation, automatically
detecting gzip-compressed data and decompressing it.
|
static byte[] |
decode(String s,
int options)
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,
int options)
Decodes four bytes from array source
and writes the resulting bytes (up to three of them)
to destination.
|
static void |
decodeFileToFile(String infile,
String outfile)
Reads infile and decodes it to outfile.
|
static byte[] |
decodeFromFile(String filename)
Convenience method for reading a base64-encoded
file and decoding it.
|
static boolean |
decodeToFile(String dataToDecode,
String filename)
Convenience method for decoding data to a file.
|
static Object |
decodeToObject(String encodedObject)
Attempts to decode Base64 data and deserialize a Java
Object within.
|
private static byte[] |
encode3to4(byte[] b4,
byte[] threeBytes,
int numSigBytes,
int options)
Encodes up to the first three bytes of array threeBytes
and returns a four-byte array in Base64 notation.
|
private static byte[] |
encode3to4(byte[] source,
int srcOffset,
int numSigBytes,
byte[] destination,
int destOffset,
int options)
Encodes up to three bytes of the array source
and writes the resulting four Base64 bytes to destination.
|
static String |
encodeBytes(byte[] source)
Encodes a byte array into Base64 notation.
|
static String |
encodeBytes(byte[] source,
int options)
Encodes a byte array into Base64 notation.
|
static String |
encodeBytes(byte[] source,
int off,
int len)
Encodes a byte array into Base64 notation.
|
static String |
encodeBytes(byte[] source,
int off,
int len,
int options)
Encodes a byte array into Base64 notation.
|
static void |
encodeFileToFile(String infile,
String outfile)
Reads infile and encodes it to outfile.
|
static String |
encodeFromFile(String filename)
Convenience method for reading a binary file
and base64-encoding it.
|
static String |
encodeObject(Serializable serializableObject)
Serializes an object and returns the Base64-encoded
version of that serialized object.
|
static String |
encodeObject(Serializable serializableObject,
int options)
Serializes an object and returns the Base64-encoded
version of that serialized object.
|
static boolean |
encodeToFile(byte[] dataToEncode,
String filename)
Convenience method for encoding data to a file.
|
private static byte[] |
getAlphabet(int options)
Returns one of the _SOMETHING_ALPHABET byte arrays depending on
the options specified.
|
private static byte[] |
getDecodabet(int options)
Returns one of the _SOMETHING_DECODABET byte arrays depending on
the options specified.
|
private static void |
usage(String msg)
Prints command line usage.
|
public static final int NO_OPTIONS
public static final int ENCODE
public static final int DECODE
public static final int GZIP
public static final int DONT_BREAK_LINES
public static final int URL_SAFE
public static final int ORDERED
private static final int MAX_LINE_LENGTH
private static final byte EQUALS_SIGN
private static final byte NEW_LINE
private static final String PREFERRED_ENCODING
private static final byte WHITE_SPACE_ENC
private static final byte EQUALS_SIGN_ENC
private static final byte[] _STANDARD_ALPHABET
private static final byte[] _STANDARD_DECODABET
private static final byte[] _URL_SAFE_ALPHABET
private static final byte[] _URL_SAFE_DECODABET
private static final byte[] _ORDERED_ALPHABET
private static final byte[] _ORDERED_DECODABET
private Base64()
private static final byte[] getAlphabet(int options)
private static final byte[] getDecodabet(int options)
private static final void usage(String msg)
msg
- A message to include with usage info.private static byte[] encode3to4(byte[] b4, byte[] threeBytes, int numSigBytes, int options)
b4
- A reusable byte array to reduce array instantiationthreeBytes
- the array to convertnumSigBytes
- the number of significant bytes in your arrayprivate static byte[] encode3to4(byte[] source, int srcOffset, int numSigBytes, byte[] destination, int destOffset, int options)
Encodes up to three bytes of the array source and writes the resulting four Base64 bytes to destination. The source and destination arrays can be manipulated anywhere along their length by specifying srcOffset and destOffset. This method does not check to make sure your arrays are large enough to accomodate srcOffset + 3 for the source array or destOffset + 4 for the destination array. The actual number of significant bytes in your array is given by numSigBytes.
This is the lowest level of the encoding methods with all possible parameters.
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 String encodeObject(Serializable serializableObject)
serializableObject
- The object to encodepublic static String encodeObject(Serializable serializableObject, int options)
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: encodeObject( myObj, Base64.GZIP )
or
Example: encodeObject( myObj, Base64.GZIP | Base64.DONT_BREAK_LINES )
serializableObject
- The object to encodeoptions
- Specified optionsGZIP
,
DONT_BREAK_LINES
public static String encodeBytes(byte[] source)
source
- The data to convertpublic static String encodeBytes(byte[] source, int options)
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 optionsGZIP
,
DONT_BREAK_LINES
public static 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 String encodeBytes(byte[] source, int off, int len, int options)
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 options
alphabet type is pulled from this (standard, url-safe, ordered)GZIP
,
DONT_BREAK_LINES
private static int decode4to3(byte[] source, int srcOffset, byte[] destination, int destOffset, int options)
This is the lowest level of the decoding methods with all possible parameters.
source
- the array to convertsrcOffset
- the index where conversion beginsdestination
- the array to hold the conversiondestOffset
- the index where output will be putoptions
- alphabet type is pulled from this (standard, url-safe, ordered)public static byte[] decode(byte[] source, int off, int len, int options)
source
- The Base64 encoded dataoff
- The offset of where to begin decodinglen
- The length of characters to decodepublic static byte[] decode(String s)
s
- the string to decodepublic static byte[] decode(String s, int options)
s
- the string to decodeoptions
- encode options such as URL_SAFEpublic static Object decodeToObject(String encodedObject)
encodedObject
- The Base64 data to decodepublic static boolean encodeToFile(byte[] dataToEncode, String filename)
dataToEncode
- byte array of data to encode in base64 formfilename
- Filename for saving encoded datapublic static boolean decodeToFile(String dataToDecode, String filename)
dataToDecode
- Base64-encoded data as a stringfilename
- Filename for saving decoded datapublic static byte[] decodeFromFile(String filename)
filename
- Filename for reading encoded datapublic static String encodeFromFile(String filename)
filename
- Filename for reading binary datapublic static void encodeFileToFile(String infile, String outfile)
infile
- Input fileoutfile
- Output filepublic static void decodeFileToFile(String infile, String outfile)
infile
- Input fileoutfile
- Output fileWebARTS Library Licensed Under the GNU - General Public License. Other Libraries licensed under their respective Open Source Licenses