Class Base64
This class implements section 6.8. Base64 Content-Transfer-Encoding from RFC 2045 Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies by Freed and Borenstein.
The class can be parameterized in the following manner with various constructors:
- URL-safe mode: Default off.
- Line length: Default 76. Line length that aren't multiples of 4 will still essentially end up being multiples of 4 in the encoded data.
- Line separator: Default is CRLF ("\r\n")
Since this class operates directly on byte streams, and not character streams, it is hard-coded to only encode/decode character encodings which are compatible with the lower 127 ASCII chart (ISO-8859-1, Windows-1252, UTF-8, etc).
- Since:
- 1.0
- Version:
- $Id: Base64.java 801706 2009-08-06 16:27:06Z niallp $
- Author:
- Apache Software Foundation
- See Also:
-
Constructor Summary
ConstructorDescriptionBase64()
Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.Base64
(boolean urlSafe) Creates a Base64 codec used for decoding (all modes) and encoding in the given URL-safe mode.Base64
(int lineLength) Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.Base64
(int lineLength, byte[] lineSeparator) Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.Base64
(int lineLength, byte[] lineSeparator, boolean urlSafe) Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode. -
Method Summary
Modifier and TypeMethodDescriptionbyte[]
decode
(byte[] pArray) Decodes a byte[] containing containing characters in the Base64 alphabet.Decodes an Object using the base64 algorithm.byte[]
Decodes a String containing containing characters in the Base64 alphabet.static byte[]
decodeBase64
(byte[] base64Data) Decodes Base64 data into octetsstatic byte[]
decodeBase64
(String base64String) Decodes a Base64 String into octetsstatic BigInteger
decodeInteger
(byte[] pArray) Decodes a byte64-encoded integer according to crypto standards such as W3C's XML-Signaturebyte[]
encode
(byte[] pArray) Encodes a byte[] containing binary data, into a byte[] containing characters in the Base64 alphabet.Encodes an Object using the base64 algorithm.static byte[]
encodeBase64
(byte[] binaryData) Encodes binary data using the base64 algorithm but does not chunk the output.static byte[]
encodeBase64
(byte[] binaryData, boolean isChunked) Encodes binary data using the base64 algorithm, optionally chunking the output into 76 character blocks.static byte[]
encodeBase64
(byte[] binaryData, boolean isChunked, boolean urlSafe) Encodes binary data using the base64 algorithm, optionally chunking the output into 76 character blocks.static byte[]
encodeBase64
(byte[] binaryData, boolean isChunked, boolean urlSafe, int maxResultSize) Encodes binary data using the base64 algorithm, optionally chunking the output into 76 character blocks.static byte[]
encodeBase64Chunked
(byte[] binaryData) Encodes binary data using the base64 algorithm and chunks the encoded output into 76 character blocksstatic String
encodeBase64String
(byte[] binaryData) Encodes binary data using the base64 algorithm into 76 character blocks separated by CRLF.static byte[]
encodeBase64URLSafe
(byte[] binaryData) Encodes binary data using a URL-safe variation of the base64 algorithm but does not chunk the output.static String
encodeBase64URLSafeString
(byte[] binaryData) Encodes binary data using a URL-safe variation of the base64 algorithm but does not chunk the output.static byte[]
encodeInteger
(BigInteger bigInt) Encodes to a byte64-encoded integer according to crypto standards such as W3C's XML-SignatureencodeToString
(byte[] pArray) Encodes a byte[] containing binary data, into a String containing characters in the Base64 alphabet.static boolean
isArrayByteBase64
(byte[] arrayOctet) Tests a given byte array to see if it contains only valid characters within the Base64 alphabet.static boolean
isBase64
(byte octet) Returns whether or not theoctet
is in the base 64 alphabet.boolean
Returns our current encode mode.
-
Constructor Details
-
Base64
public Base64()Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.When encoding the line length is 76, the line separator is CRLF, and the encoding table is STANDARD_ENCODE_TABLE.
When decoding all variants are supported.
-
Base64
public Base64(boolean urlSafe) Creates a Base64 codec used for decoding (all modes) and encoding in the given URL-safe mode.When encoding the line length is 76, the line separator is CRLF, and the encoding table is STANDARD_ENCODE_TABLE.
When decoding all variants are supported.
- Parameters:
urlSafe
- iftrue
, URL-safe encoding is used. In most cases this should be set tofalse
.- Since:
- 1.4
-
Base64
public Base64(int lineLength) Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.When encoding the line length is given in the constructor, the line separator is CRLF, and the encoding table is STANDARD_ENCODE_TABLE.
Line lengths that aren't multiples of 4 will still essentially end up being multiples of 4 in the encoded data.
When decoding all variants are supported.
- Parameters:
lineLength
- Each line of encoded data will be at most of the given length (rounded down to nearest multiple of 4). If lineLength <= 0, then the output will not be divided into lines (chunks). Ignored when decoding.- Since:
- 1.4
-
Base64
public Base64(int lineLength, byte[] lineSeparator) Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.When encoding the line length and line separator are given in the constructor, and the encoding table is STANDARD_ENCODE_TABLE.
Line lengths that aren't multiples of 4 will still essentially end up being multiples of 4 in the encoded data.
When decoding all variants are supported.
- Parameters:
lineLength
- Each line of encoded data will be at most of the given length (rounded down to nearest multiple of 4). If lineLength <= 0, then the output will not be divided into lines (chunks). Ignored when decoding.lineSeparator
- Each line of encoded data will end with this sequence of bytes.- Throws:
IllegalArgumentException
- Thrown when the provided lineSeparator included some base64 characters.- Since:
- 1.4
-
Base64
public Base64(int lineLength, byte[] lineSeparator, boolean urlSafe) Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.When encoding the line length and line separator are given in the constructor, and the encoding table is STANDARD_ENCODE_TABLE.
Line lengths that aren't multiples of 4 will still essentially end up being multiples of 4 in the encoded data.
When decoding all variants are supported.
- Parameters:
lineLength
- Each line of encoded data will be at most of the given length (rounded down to nearest multiple of 4). If lineLength <= 0, then the output will not be divided into lines (chunks). Ignored when decoding.lineSeparator
- Each line of encoded data will end with this sequence of bytes.urlSafe
- Instead of emitting '+' and '/' we emit '-' and '_' respectively. urlSafe is only applied to encode operations. Decoding seamlessly handles both modes.- Throws:
IllegalArgumentException
- The provided lineSeparator included some base64 characters. That's not going to work!- Since:
- 1.4
-
-
Method Details
-
isUrlSafe
public boolean isUrlSafe()Returns our current encode mode. True if we're URL-SAFE, false otherwise.- Returns:
- true if we're in URL-SAFE mode, false otherwise.
- Since:
- 1.4
-
isBase64
public static boolean isBase64(byte octet) Returns whether or not theoctet
is in the base 64 alphabet.- Parameters:
octet
- The value to test- Returns:
true
if the value is defined in the the base 64 alphabet,false
otherwise.- Since:
- 1.4
-
isArrayByteBase64
public static boolean isArrayByteBase64(byte[] arrayOctet) Tests a given byte array to see if it contains only valid characters within the Base64 alphabet. Currently the method treats whitespace as valid.- Parameters:
arrayOctet
- byte array to test- Returns:
true
if all bytes are valid characters in the Base64 alphabet or if the byte array is empty; false, otherwise
-
encodeBase64
public static byte[] encodeBase64(byte[] binaryData) Encodes binary data using the base64 algorithm but does not chunk the output.- Parameters:
binaryData
- binary data to encode- Returns:
- byte[] containing Base64 characters in their UTF-8 representation.
-
encodeBase64String
Encodes binary data using the base64 algorithm into 76 character blocks separated by CRLF.- Parameters:
binaryData
- binary data to encode- Returns:
- String containing Base64 characters.
- Since:
- 1.4
-
encodeBase64URLSafe
public static byte[] encodeBase64URLSafe(byte[] binaryData) Encodes binary data using a URL-safe variation of the base64 algorithm but does not chunk the output. The url-safe variation emits - and _ instead of + and / characters.- Parameters:
binaryData
- binary data to encode- Returns:
- byte[] containing Base64 characters in their UTF-8 representation.
- Since:
- 1.4
-
encodeBase64URLSafeString
Encodes binary data using a URL-safe variation of the base64 algorithm but does not chunk the output. The url-safe variation emits - and _ instead of + and / characters.- Parameters:
binaryData
- binary data to encode- Returns:
- String containing Base64 characters
- Since:
- 1.4
-
encodeBase64Chunked
public static byte[] encodeBase64Chunked(byte[] binaryData) Encodes binary data using the base64 algorithm and chunks the encoded output into 76 character blocks- Parameters:
binaryData
- binary data to encode- Returns:
- Base64 characters chunked in 76 character blocks
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decode
Decodes an Object using the base64 algorithm. This method is provided in order to satisfy the requirements of the Decoder interface, and will throw a DecoderException if the supplied object is not of type byte[] or String.- Parameters:
pObject
- Object to decode- Returns:
- An object (of type byte[]) containing the binary data which corresponds to the byte[] or String supplied.
- Throws:
DecoderException
- if the parameter supplied is not of type byte[]
-
decode
Decodes a String containing containing characters in the Base64 alphabet.- Parameters:
pArray
- A String containing Base64 character data- Returns:
- a byte array containing binary data
- Since:
- 1.4
-
decode
public byte[] decode(byte[] pArray) Decodes a byte[] containing containing characters in the Base64 alphabet.- Parameters:
pArray
- A byte array containing Base64 character data- Returns:
- a byte array containing binary data
-
encodeBase64
public static byte[] encodeBase64(byte[] binaryData, boolean isChunked) Encodes binary data using the base64 algorithm, optionally chunking the output into 76 character blocks.- Parameters:
binaryData
- Array containing binary data to encode.isChunked
- iftrue
this encoder will chunk the base64 output into 76 character blocks- Returns:
- Base64-encoded data.
- Throws:
IllegalArgumentException
- Thrown when the input array needs an output array bigger thanInteger.MAX_VALUE
-
encodeBase64
public static byte[] encodeBase64(byte[] binaryData, boolean isChunked, boolean urlSafe) Encodes binary data using the base64 algorithm, optionally chunking the output into 76 character blocks.- Parameters:
binaryData
- Array containing binary data to encode.isChunked
- iftrue
this encoder will chunk the base64 output into 76 character blocksurlSafe
- iftrue
this encoder will emit - and _ instead of the usual + and / characters.- Returns:
- Base64-encoded data.
- Throws:
IllegalArgumentException
- Thrown when the input array needs an output array bigger thanInteger.MAX_VALUE
- Since:
- 1.4
-
encodeBase64
public static byte[] encodeBase64(byte[] binaryData, boolean isChunked, boolean urlSafe, int maxResultSize) Encodes binary data using the base64 algorithm, optionally chunking the output into 76 character blocks.- Parameters:
binaryData
- Array containing binary data to encode.isChunked
- iftrue
this encoder will chunk the base64 output into 76 character blocksurlSafe
- iftrue
this encoder will emit - and _ instead of the usual + and / characters.maxResultSize
- The maximum result size to accept.- Returns:
- Base64-encoded data.
- Throws:
IllegalArgumentException
- Thrown when the input array needs an output array bigger than maxResultSize- Since:
- 1.4
-
decodeBase64
Decodes a Base64 String into octets- Parameters:
base64String
- String containing Base64 data- Returns:
- Array containing decoded data.
- Since:
- 1.4
-
decodeBase64
public static byte[] decodeBase64(byte[] base64Data) Decodes Base64 data into octets- Parameters:
base64Data
- Byte array containing Base64 data- Returns:
- Array containing decoded data.
-
encode
Encodes an Object using the base64 algorithm. This method is provided in order to satisfy the requirements of the Encoder interface, and will throw an EncoderException if the supplied object is not of type byte[].- Parameters:
pObject
- Object to encode- Returns:
- An object (of type byte[]) containing the base64 encoded data which corresponds to the byte[] supplied.
- Throws:
EncoderException
- if the parameter supplied is not of type byte[]
-
encodeToString
Encodes a byte[] containing binary data, into a String containing characters in the Base64 alphabet.- Parameters:
pArray
- a byte array containing binary data- Returns:
- A String containing only Base64 character data
- Since:
- 1.4
-
encode
public byte[] encode(byte[] pArray) Encodes a byte[] containing binary data, into a byte[] containing characters in the Base64 alphabet.- Parameters:
pArray
- a byte array containing binary data- Returns:
- A byte array containing only Base64 character data
-
decodeInteger
Decodes a byte64-encoded integer according to crypto standards such as W3C's XML-Signature- Parameters:
pArray
- a byte array containing base64 character data- Returns:
- A BigInteger
- Since:
- 1.4
-
encodeInteger
Encodes to a byte64-encoded integer according to crypto standards such as W3C's XML-Signature- Parameters:
bigInt
- a BigInteger- Returns:
- A byte array containing base64 character data
- Throws:
NullPointerException
- if null is passed in- Since:
- 1.4
-