public class Base64 extends BaseNCodec
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:
The URL-safe parameter is only applied to encode operations. Decoding seamlessly handles both modes.
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).
This class is thread-safe.
lineLength, MASK_8BITS, MIME_CHUNK_SIZE, pad, PAD_DEFAULT, PEM_CHUNK_SIZE
Constructor and Description |
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Base64()
Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.
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Base64(boolean urlSafe)
Creates a Base64 codec used for decoding (all modes) and encoding in the given URL-safe mode.
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Base64(int lineLength)
Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.
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Base64(int lineLength,
byte[] lineSeparator)
Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.
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Base64(int lineLength,
byte[] lineSeparator,
boolean urlSafe)
Creates a Base64 codec used for decoding (all modes) and encoding in URL-unsafe mode.
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Modifier and Type | Method and Description |
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static byte[] |
decodeBase64(byte[] base64Data)
Decodes Base64 data into octets.
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static byte[] |
decodeBase64(String base64String)
Decodes a Base64 String into octets.
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static BigInteger |
decodeInteger(byte[] pArray)
Decodes a byte64-encoded integer according to crypto standards such as W3C's XML-Signature.
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static byte[] |
encodeBase64(byte[] binaryData)
Encodes binary data using the base64 algorithm but does not chunk the output.
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static byte[] |
encodeBase64(byte[] binaryData,
boolean isChunked)
Encodes binary data using the base64 algorithm, optionally chunking the output into 76 character blocks.
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static byte[] |
encodeBase64(byte[] binaryData,
boolean isChunked,
boolean urlSafe)
Encodes binary data using the base64 algorithm, optionally chunking the output into 76 character blocks.
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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.
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static byte[] |
encodeBase64Chunked(byte[] binaryData)
Encodes binary data using the base64 algorithm and chunks the encoded output into 76 character blocks
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static String |
encodeBase64String(byte[] binaryData)
Encodes binary data using the base64 algorithm but does not chunk the output.
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static byte[] |
encodeBase64URLSafe(byte[] binaryData)
Encodes binary data using a URL-safe variation of the base64 algorithm but does not chunk the output.
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static String |
encodeBase64URLSafeString(byte[] binaryData)
Encodes binary data using a URL-safe variation of the base64 algorithm but does not chunk the output.
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static byte[] |
encodeInteger(BigInteger bigInt)
Encodes to a byte64-encoded integer according to crypto standards such as W3C's XML-Signature.
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static boolean |
isBase64(byte octet)
Returns whether or not the
octet is in the base 64 alphabet. |
static boolean |
isBase64(byte[] arrayOctet)
Tests a given byte array to see if it contains only valid characters within the Base64 alphabet.
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static boolean |
isBase64(String base64)
Tests a given String to see if it contains only valid characters within the Base64 alphabet.
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protected boolean |
isInAlphabet(byte octet)
Returns whether or not the
octet is in the Base64 alphabet. |
boolean |
isUrlSafe()
Returns our current encode mode.
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containsAlphabetOrPad, decode, decode, decode, encode, encode, encode, encodeAsString, encodeToString, ensureBufferSize, getDefaultBufferSize, getEncodedLength, isInAlphabet, isInAlphabet, isWhiteSpace
public Base64()
When encoding the line length is 0 (no chunking), and the encoding table is STANDARD_ENCODE_TABLE.
When decoding all variants are supported.
public Base64(boolean urlSafe)
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.
urlSafe
- if true
, URL-safe encoding is used. In most cases this should be set to
false
.public Base64(int lineLength)
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.
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.public Base64(int lineLength, byte[] lineSeparator)
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.
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.IllegalArgumentException
- Thrown when the provided lineSeparator included some base64 characters.public Base64(int lineLength, byte[] lineSeparator, boolean urlSafe)
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.
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.
Note: no padding is added when using the URL-safe alphabet.IllegalArgumentException
- The provided lineSeparator included some base64 characters. That's not going to work!public static byte[] decodeBase64(byte[] base64Data)
Note: this method seamlessly handles data encoded in URL-safe or normal mode.
base64Data
- Byte array containing Base64 datapublic static byte[] decodeBase64(String base64String)
Note: this method seamlessly handles data encoded in URL-safe or normal mode.
base64String
- String containing Base64 datapublic static BigInteger decodeInteger(byte[] pArray)
pArray
- a byte array containing base64 character datapublic static byte[] encodeBase64(byte[] binaryData)
binaryData
- binary data to encodepublic static byte[] encodeBase64(byte[] binaryData, boolean isChunked)
binaryData
- Array containing binary data to encode.isChunked
- if true
this encoder will chunk the base64 output into 76 character blocksIllegalArgumentException
- Thrown when the input array needs an output array bigger than Integer.MAX_VALUE
public static byte[] encodeBase64(byte[] binaryData, boolean isChunked, boolean urlSafe)
binaryData
- Array containing binary data to encode.isChunked
- if true
this encoder will chunk the base64 output into 76 character blocksurlSafe
- if true
this encoder will emit - and _ instead of the usual + and / characters.
Note: no padding is added when encoding using the URL-safe alphabet.IllegalArgumentException
- Thrown when the input array needs an output array bigger than Integer.MAX_VALUE
public static byte[] encodeBase64(byte[] binaryData, boolean isChunked, boolean urlSafe, int maxResultSize)
binaryData
- Array containing binary data to encode.isChunked
- if true
this encoder will chunk the base64 output into 76 character blocksurlSafe
- if true
this encoder will emit - and _ instead of the usual + and / characters.
Note: no padding is added when encoding using the URL-safe alphabet.maxResultSize
- The maximum result size to accept.IllegalArgumentException
- Thrown when the input array needs an output array bigger than maxResultSizepublic static byte[] encodeBase64Chunked(byte[] binaryData)
binaryData
- binary data to encodepublic static String encodeBase64String(byte[] binaryData)
binaryData
- binary data to encodepublic static byte[] encodeBase64URLSafe(byte[] binaryData)
binaryData
- binary data to encodepublic static String encodeBase64URLSafeString(byte[] binaryData)
binaryData
- binary data to encodepublic static byte[] encodeInteger(BigInteger bigInt)
bigInt
- a BigIntegerNullPointerException
- if null is passed inpublic static boolean isBase64(byte octet)
octet
is in the base 64 alphabet.octet
- The value to testtrue
if the value is defined in the the base 64 alphabet, false
otherwise.public static boolean isBase64(byte[] arrayOctet)
arrayOctet
- byte array to testtrue
if all bytes are valid characters in the Base64 alphabet or if the byte array is empty;
false
, otherwisepublic static boolean isBase64(String base64)
base64
- String to testtrue
if all characters in the String are valid characters in the Base64 alphabet or if
the String is empty; false
, otherwiseprotected boolean isInAlphabet(byte octet)
octet
is in the Base64 alphabet.isInAlphabet
in class BaseNCodec
octet
- The value to testtrue
if the value is defined in the the Base64 alphabet false
otherwise.public boolean isUrlSafe()