Package org.apache.commons.codec.binary

Class Base32

java.lang.Object

org.apache.commons.codec.binary.BaseNCodec

org.apache.commons.codec.binary.Base32

All Implemented Interfaces:

BinaryDecoder, BinaryEncoder, Decoder, Encoder

public class Base32
extends BaseNCodec

Provides Base32 encoding and decoding as defined by RFC 4648.

The class can be parameterized in the following manner with various constructors:

• Whether to use the "base32hex" variant instead of the default "base32"
• Line length: Default 76. Line length that aren't multiples of 8 will still essentially end up being multiples of 8 in the encoded data.
• Line separator: Default is CRLF ("\r\n")

This class operates directly on byte streams, and not character streams.

This class is thread-safe.

Since:

1.5

See Also:

RFC 4648

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.commons.codec.binary.BaseNCodec

BaseNCodec.Context

Field Summary

Fields inherited from class org.apache.commons.codec.binary.BaseNCodec

CHUNK_SEPARATOR, DECODING_POLICY_DEFAULT, EOF, lineLength, MASK_8BITS, MIME_CHUNK_SIZE, pad, PAD, PAD_DEFAULT, PEM_CHUNK_SIZE

Constructor Summary

Constructors

Constructor	Description
Base32()	Creates a Base32 codec used for decoding and encoding.
Base32(boolean useHex)	Creates a Base32 codec used for decoding and encoding.
Base32(boolean useHex, byte padding)	Creates a Base32 codec used for decoding and encoding.
Base32(byte pad)	Creates a Base32 codec used for decoding and encoding.
Base32(int lineLength)	Creates a Base32 codec used for decoding and encoding.
Base32(int lineLength, byte[] lineSeparator)	Creates a Base32 codec used for decoding and encoding.
Base32(int lineLength, byte[] lineSeparator, boolean useHex)	Creates a Base32 / Base32 Hex codec used for decoding and encoding.
Base32(int lineLength, byte[] lineSeparator, boolean useHex, byte padding)	Creates a Base32 / Base32 Hex codec used for decoding and encoding.
Base32(int lineLength, byte[] lineSeparator, boolean useHex, byte padding, CodecPolicy decodingPolicy)	Creates a Base32 / Base32 Hex codec used for decoding and encoding.

Method Summary

Modifier and Type	Method	Description
(package private) void	decode(byte[] input, int inPos, int inAvail, BaseNCodec.Context context)	Decodes all of the provided data, starting at inPos, for inAvail bytes.
(package private) void	encode(byte[] input, int inPos, int inAvail, BaseNCodec.Context context)	Encodes all of the provided data, starting at inPos, for inAvail bytes.
boolean	isInAlphabet(byte octet)	Returns whether or not the octet is in the Base32 alphabet.

Methods inherited from class org.apache.commons.codec.binary.BaseNCodec

available, containsAlphabetOrPad, decode, decode, decode, encode, encode, encode, encodeAsString, encodeToString, ensureBufferSize, getChunkSeparator, getCodecPolicy, getDefaultBufferSize, getEncodedLength, hasData, isInAlphabet, isInAlphabet, isStrictDecoding, isWhiteSpace, readResults

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Base32

public Base32()

Creates a Base32 codec used for decoding and encoding.

When encoding the line length is 0 (no chunking).

Base32

public Base32(boolean useHex)

Creates a Base32 codec used for decoding and encoding.

When encoding the line length is 0 (no chunking).

Parameters:

useHex - if true then use Base32 Hex alphabet

Base32

public Base32(boolean useHex,
              byte padding)

Creates a Base32 codec used for decoding and encoding.

When encoding the line length is 0 (no chunking).

Parameters:

useHex - if true then use Base32 Hex alphabet

padding - byte used as padding byte.

Base32

public Base32(byte pad)

Creates a Base32 codec used for decoding and encoding.

When encoding the line length is 0 (no chunking).

Parameters:

pad - byte used as padding byte.

Base32

public Base32(int lineLength)

Creates a Base32 codec used for decoding and encoding.

When encoding the line length is given in the constructor, the line separator is CRLF.

Parameters:

lineLength - Each line of encoded data will be at most of the given length (rounded down to nearest multiple of 8). If lineLength <= 0, then the output will not be divided into lines (chunks). Ignored when decoding.

Base32

public Base32(int lineLength,
              byte[] lineSeparator)

Creates a Base32 codec used for decoding and encoding.

When encoding the line length and line separator are given in the constructor.

Line lengths that aren't multiples of 8 will still essentially end up being multiples of 8 in the encoded data.

Parameters:

lineLength - Each line of encoded data will be at most of the given length (rounded down to nearest multiple of 8). 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 lineSeparator contains Base32 characters.

Base32

public Base32(int lineLength,
              byte[] lineSeparator,
              boolean useHex)

Creates a Base32 / Base32 Hex codec used for decoding and encoding.

When encoding the line length and line separator are given in the constructor.

Line lengths that aren't multiples of 8 will still essentially end up being multiples of 8 in the encoded data.

Parameters:

lineLength - Each line of encoded data will be at most of the given length (rounded down to nearest multiple of 8). 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.

useHex - if true, then use Base32 Hex alphabet, otherwise use Base32 alphabet

Throws:

IllegalArgumentException - Thrown when the lineSeparator contains Base32 characters. Or the lineLength > 0 and lineSeparator is null.

Base32

public Base32(int lineLength,
              byte[] lineSeparator,
              boolean useHex,
              byte padding)

Creates a Base32 / Base32 Hex codec used for decoding and encoding.

When encoding the line length and line separator are given in the constructor.

Line lengths that aren't multiples of 8 will still essentially end up being multiples of 8 in the encoded data.

Parameters:

lineLength - Each line of encoded data will be at most of the given length (rounded down to nearest multiple of 8). 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.

useHex - if true, then use Base32 Hex alphabet, otherwise use Base32 alphabet

padding - byte used as padding byte.

Throws:

IllegalArgumentException - Thrown when the lineSeparator contains Base32 characters. Or the lineLength > 0 and lineSeparator is null.

Base32

public Base32(int lineLength,
              byte[] lineSeparator,
              boolean useHex,
              byte padding,
              CodecPolicy decodingPolicy)

Creates a Base32 / Base32 Hex codec used for decoding and encoding.

When encoding the line length and line separator are given in the constructor.

Line lengths that aren't multiples of 8 will still essentially end up being multiples of 8 in the encoded data.

Parameters:

lineLength - Each line of encoded data will be at most of the given length (rounded down to nearest multiple of 8). 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.

useHex - if true, then use Base32 Hex alphabet, otherwise use Base32 alphabet

padding - byte used as padding byte.

decodingPolicy - The decoding policy.

Throws:

IllegalArgumentException - Thrown when the lineSeparator contains Base32 characters. Or the lineLength > 0 and lineSeparator is null.

Since:

1.15

Method Detail

decode

void decode(byte[] input,
            int inPos,
            int inAvail,
            BaseNCodec.Context context)

Decodes all of the provided data, starting at inPos, for inAvail bytes. Should be called at least twice: once with the data to decode, and once with inAvail set to "-1" to alert decoder that EOF has been reached. The "-1" call is not necessary when decoding, but it doesn't hurt, either.

Ignores all non-Base32 characters. This is how chunked (e.g. 76 character) data is handled, since CR and LF are silently ignored, but has implications for other bytes, too. This method subscribes to the garbage-in, garbage-out philosophy: it will not check the provided data for validity.

Output is written to Context#buffer as 8-bit octets, using Context#pos as the buffer position

Specified by:

decode in class BaseNCodec

Parameters:

input - byte[] array of ascii data to Base32 decode.

inPos - Position to start reading data from.

inAvail - Amount of bytes available from input for decoding.

context - the context to be used

encode

void encode(byte[] input,
            int inPos,
            int inAvail,
            BaseNCodec.Context context)

Encodes all of the provided data, starting at inPos, for inAvail bytes. Must be called at least twice: once with the data to encode, and once with inAvail set to "-1" to alert encoder that EOF has been reached, so flush last remaining bytes (if not multiple of 5).

Specified by:

encode in class BaseNCodec

Parameters:

input - byte[] array of binary data to Base32 encode.

inPos - Position to start reading data from.

inAvail - Amount of bytes available from input for encoding.

context - the context to be used

isInAlphabet

public boolean isInAlphabet(byte octet)

Returns whether or not the octet is in the Base32 alphabet.

Specified by:

isInAlphabet in class BaseNCodec

Parameters:

octet - The value to test

Returns:

true if the value is defined in the the Base32 alphabet false otherwise.