Class Base64
Example:
String encoded = Base64.encode(myByteArray); byte[] myByteArray = Base64.decode(encoded);
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(byte[], int)
the options parameter can be used to indicate such things as
first gzipping the bytes before encoding them, not inserting linefeeds, and encoding using the
URL-safe and Ordered dialects.
Note, according to RFC3548, Section 2.1, implementations should not add line feeds unless explicitly told to do so. I've got Base64 set to this behavior now, although earlier versions broke lines by default.
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.DO_BREAK_LINES);
to compress the data before encoding it and then making the output have newline characters.
- Version:
- 2.3.7
-
Nested Class Summary
Nested ClassesModifier and TypeClassDescriptionstatic class
ABase64.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
ABase64.OutputStream
will write data to another java.io.OutputStream, given in the constructor, and encode/decode to/from Base64 notation on the fly. -
Field Summary
FieldsModifier and TypeFieldDescriptionstatic final int
Specify decoding in first bit.static final int
Do break lines when encoding.static final int
Specify that gzipped data should not be automatically gunzipped.static final int
Specify encoding in first bit.static final int
Specify that data should be gzip-compressed in second bit.static final int
No options specified.static final int
Encode using the special "ordered" dialect of Base64 described here: http://www.faqs.org/qa/rfcc-1940.html.static final int
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. -
Method Summary
Modifier and TypeMethodDescriptionstatic byte[]
decode
(byte[] source) Low-level access to decoding ASCII characters in the form of a byte array.static byte[]
decode
(byte[] source, int off, int len, int options) Low-level access to decoding ASCII characters in the form of a byte array.static byte[]
Decodes data from Base64 notation, automatically detecting gzip-compressed data and decompressing it.static byte[]
Decodes data from Base64 notation, automatically detecting gzip-compressed data and decompressing it.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 void
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.static Object
decodeToObject
(String encodedObject, int options, ClassLoader loader) Attempts to decode Base64 data and deserialize a Java Object within.static void
encode
(ByteBuffer raw, ByteBuffer encoded) Performs Base64 encoding on theraw
ByteBuffer, writing it to theencoded
ByteBuffer.static void
encode
(ByteBuffer raw, CharBuffer encoded) Performs Base64 encoding on theraw
ByteBuffer, writing it to theencoded
CharBuffer.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 byte[]
encodeBytesToBytes
(byte[] source) Similar toencodeBytes(byte[])
but returns a byte array instead of instantiating a String.static byte[]
encodeBytesToBytes
(byte[] source, int off, int len, int options) Similar toencodeBytes(byte[], int, int, int)
but returns a byte array instead of instantiating a String.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 void
encodeToFile
(byte[] dataToEncode, String filename) Convenience method for encoding data to a file.
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Field Details
-
NO_OPTIONS
public static final int NO_OPTIONSNo options specified. Value is zero.- See Also:
-
ENCODE
public static final int ENCODESpecify encoding in first bit. Value is one.- See Also:
-
DECODE
public static final int DECODESpecify decoding in first bit. Value is zero.- See Also:
-
GZIP
public static final int GZIPSpecify that data should be gzip-compressed in second bit. Value is two.- See Also:
-
DONT_GUNZIP
public static final int DONT_GUNZIPSpecify that gzipped data should not be automatically gunzipped.- See Also:
-
DO_BREAK_LINES
public static final int DO_BREAK_LINESDo break lines when encoding. Value is 8.- See Also:
-
URL_SAFE
public static final int URL_SAFEEncode using Base64-like encoding that is URL- and Filename-safe as described in Section 4 of RFC3548: http://www.faqs.org/rfcs/rfc3548.html. It is important to note that data encoded this way is not officially valid Base64, or at the very least should not be called Base64 without also specifying that is was encoded using the URL- and Filename-safe dialect.- See Also:
-
ORDERED
public static final int ORDEREDEncode using the special "ordered" dialect of Base64 described here: http://www.faqs.org/qa/rfcc-1940.html.- See Also:
-
-
Method Details
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encode
Performs Base64 encoding on theraw
ByteBuffer, writing it to theencoded
ByteBuffer. This is an experimental feature. Currently it does not pass along any options (such asDO_BREAK_LINES
orGZIP
.- Parameters:
raw
- input bufferencoded
- output buffer- Since:
- 2.3
-
encode
Performs Base64 encoding on theraw
ByteBuffer, writing it to theencoded
CharBuffer. This is an experimental feature. Currently it does not pass along any options (such asDO_BREAK_LINES
orGZIP
.- Parameters:
raw
- input bufferencoded
- output buffer- Since:
- 2.3
-
encodeObject
Serializes an object and returns the Base64-encoded version of that serialized object.As of v 2.3, if the object cannot be serialized or there is another error, the method will throw an java.io.IOException. This is new to v2.3! In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
The object is not GZip-compressed before being encoded.- Parameters:
serializableObject
- The object to encode- Returns:
- The Base64-encoded object
- Throws:
IOException
- if there is an errorNullPointerException
- if serializedObject is null- Since:
- 1.4
-
encodeObject
Serializes an object and returns the Base64-encoded version of that serialized object.As of v 2.3, if the object cannot be serialized or there is another error, the method will throw an java.io.IOException. This is new to v2.3! In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
The object is not GZip-compressed before being encoded.Example options:
GZIP: gzip-compresses object before encoding it. DO_BREAK_LINES: break lines at 76 characters
Example:
encodeObject( myObj, Base64.GZIP )
orExample:
encodeObject( myObj, Base64.GZIP | Base64.DO_BREAK_LINES )
- Parameters:
serializableObject
- The object to encodeoptions
- Specified options- Returns:
- The Base64-encoded object
- Throws:
IOException
- if there is an error- Since:
- 2.0
- See Also:
-
encodeBytes
Encodes a byte array into Base64 notation. Does not GZip-compress data.- Parameters:
source
- The data to convert- Returns:
- The data in Base64-encoded form
- Throws:
NullPointerException
- if source array is null- Since:
- 1.4
-
encodeBytes
Encodes a byte array into Base64 notation.Example options:
GZIP: gzip-compresses object before encoding it. DO_BREAK_LINES: break lines at 76 characters Note: Technically, this makes your encoding non-compliant.
Example:
encodeBytes( myData, Base64.GZIP )
orExample:
encodeBytes( myData, Base64.GZIP | Base64.DO_BREAK_LINES )
As of v 2.3, if there is an error with the GZIP stream, the method will throw an java.io.IOException. This is new to v2.3! In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
- Parameters:
source
- The data to convertoptions
- Specified options- Returns:
- The Base64-encoded data as a String
- Throws:
IOException
- if there is an errorNullPointerException
- if source array is null- Since:
- 2.0
- See Also:
-
encodeBytes
Encodes a byte array into Base64 notation. Does not GZip-compress data.As of v 2.3, if there is an error, the method will throw an java.io.IOException. This is new to v2.3! In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
- Parameters:
source
- The data to convertoff
- Offset in array where conversion should beginlen
- Length of data to convert- Returns:
- The Base64-encoded data as a String
- Throws:
NullPointerException
- if source array is nullIllegalArgumentException
- if source array, offset, or length are invalid- Since:
- 1.4
-
encodeBytes
Encodes a byte array into Base64 notation.Example options:
GZIP: gzip-compresses object before encoding it. DO_BREAK_LINES: break lines at 76 characters Note: Technically, this makes your encoding non-compliant.
Example:
encodeBytes( myData, Base64.GZIP )
orExample:
encodeBytes( myData, Base64.GZIP | Base64.DO_BREAK_LINES )
As of v 2.3, if there is an error with the GZIP stream, the method will throw an java.io.IOException. This is new to v2.3! In earlier versions, it just returned a null value, but in retrospect that's a pretty poor way to handle it.
- Parameters:
source
- The data to convertoff
- Offset in array where conversion should beginlen
- Length of data to convertoptions
- Specified options- Returns:
- The Base64-encoded data as a String
- Throws:
IOException
- if there is an errorNullPointerException
- if source array is nullIllegalArgumentException
- if source array, offset, or length are invalid- Since:
- 2.0
- See Also:
-
encodeBytesToBytes
public static byte[] encodeBytesToBytes(byte[] source) Similar toencodeBytes(byte[])
but returns a byte array instead of instantiating a String. This is more efficient if you're working with I/O streams and have large data sets to encode.- Parameters:
source
- The data to convert- Returns:
- The Base64-encoded data as a byte[] (of ASCII characters)
- Throws:
NullPointerException
- if source array is null- Since:
- 2.3.1
-
encodeBytesToBytes
public static byte[] encodeBytesToBytes(byte[] source, int off, int len, int options) throws IOException Similar toencodeBytes(byte[], int, int, int)
but returns a byte array instead of instantiating a String. This is more efficient if you're working with I/O streams and have large data sets to encode.- Parameters:
source
- The data to convertoff
- Offset in array where conversion should beginlen
- Length of data to convertoptions
- Specified options- Returns:
- The Base64-encoded data as a String
- Throws:
IOException
- if there is an errorNullPointerException
- if source array is nullIllegalArgumentException
- if source array, offset, or length are invalid- Since:
- 2.3.1
- See Also:
-
decode
Low-level access to decoding ASCII characters in the form of a byte array. Ignores GUNZIP option, if it's set. This is not generally a recommended method, although it is used internally as part of the decoding process. Special case: if len = 0, an empty array is returned. Still, if you need more speed and reduced memory footprint (and aren't gzipping), consider this method.- Parameters:
source
- The Base64 encoded data- Returns:
- decoded data
- Throws:
IOException
- Since:
- 2.3.1
-
decode
Low-level access to decoding ASCII characters in the form of a byte array. Ignores GUNZIP option, if it's set. This is not generally a recommended method, although it is used internally as part of the decoding process. Special case: if len = 0, an empty array is returned. Still, if you need more speed and reduced memory footprint (and aren't gzipping), consider this method.- Parameters:
source
- The Base64 encoded dataoff
- The offset of where to begin decodinglen
- The length of characters to decodeoptions
- Can specify options such as alphabet type to use- Returns:
- decoded data
- Throws:
IOException
- If bogus characters exist in source data- Since:
- 1.3
-
decode
Decodes data from Base64 notation, automatically detecting gzip-compressed data and decompressing it.- Parameters:
s
- the string to decode- Returns:
- the decoded data
- Throws:
IOException
- If there is a problem- Since:
- 1.4
-
decode
Decodes data from Base64 notation, automatically detecting gzip-compressed data and decompressing it.- Parameters:
s
- the string to decodeoptions
- encode options such as URL_SAFE- Returns:
- the decoded data
- Throws:
IOException
- if there is an errorNullPointerException
- if s is null- Since:
- 1.4
-
decodeToObject
public static Object decodeToObject(String encodedObject) throws IOException, ClassNotFoundException Attempts to decode Base64 data and deserialize a Java Object within. Returns null if there was an error.- Parameters:
encodedObject
- The Base64 data to decode- Returns:
- The decoded and deserialized object
- Throws:
NullPointerException
- if encodedObject is nullIOException
- if there is a general errorClassNotFoundException
- if the decoded object is of a class that cannot be found by the JVM- Since:
- 1.5
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decodeToObject
public static Object decodeToObject(String encodedObject, int options, ClassLoader loader) throws IOException, ClassNotFoundException Attempts to decode Base64 data and deserialize a Java Object within. Returns null if there was an error. If loader is not null, it will be the class loader used when deserializing.- Parameters:
encodedObject
- The Base64 data to decodeoptions
- Various parameters related to decodingloader
- Optional class loader to use in deserializing classes.- Returns:
- The decoded and deserialized object
- Throws:
NullPointerException
- if encodedObject is nullIOException
- if there is a general errorClassNotFoundException
- if the decoded object is of a class that cannot be found by the JVM- Since:
- 2.3.4
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encodeToFile
Convenience method for encoding data to a file.As of v 2.3, if there is a error, the method will throw an java.io.IOException. This is new to v2.3! In earlier versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
- Parameters:
dataToEncode
- byte array of data to encode in base64 formfilename
- Filename for saving encoded data- Throws:
IOException
- if there is an errorNullPointerException
- if dataToEncode is null- Since:
- 2.1
-
decodeToFile
Convenience method for decoding data to a file.As of v 2.3, if there is a error, the method will throw an java.io.IOException. This is new to v2.3! In earlier versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
- Parameters:
dataToDecode
- Base64-encoded data as a stringfilename
- Filename for saving decoded data- Throws:
IOException
- if there is an error- Since:
- 2.1
-
decodeFromFile
Convenience method for reading a base64-encoded file and decoding it.As of v 2.3, if there is a error, the method will throw an java.io.IOException. This is new to v2.3! In earlier versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
- Parameters:
filename
- Filename for reading encoded data- Returns:
- decoded byte array
- Throws:
IOException
- if there is an error- Since:
- 2.1
-
encodeFromFile
Convenience method for reading a binary file and base64-encoding it.As of v 2.3, if there is a error, the method will throw an java.io.IOException. This is new to v2.3! In earlier versions, it just returned false, but in retrospect that's a pretty poor way to handle it.
- Parameters:
filename
- Filename for reading binary data- Returns:
- base64-encoded string
- Throws:
IOException
- if there is an error- Since:
- 2.1
-
encodeFileToFile
Reads infile and encodes it to outfile.- Parameters:
infile
- Input fileoutfile
- Output file- Throws:
IOException
- if there is an error- Since:
- 2.2
-
decodeFileToFile
Reads infile and decodes it to outfile.- Parameters:
infile
- Input fileoutfile
- Output file- Throws:
IOException
- if there is an error- Since:
- 2.2
-