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
Modifier and Type	Field	Description
`private static int`	`BITS_PER_ENCODED_BYTE`	BASE32 characters are 5 bits in length.
`private static int`	`BYTES_PER_ENCODED_BLOCK`
`private static int`	`BYTES_PER_UNENCODED_BLOCK`
`private static byte[]`	`CHUNK_SEPARATOR`	Chunk separator per RFC 2045 section 2.1.
`private static byte[]`	`DECODE_TABLE`	This array is a lookup table that translates Unicode characters drawn from the "Base32 Alphabet" (as specified in Table 3 of RFC 4648) into their 5-bit positive integer equivalents.
`private int`	`decodeSize`	Convenience variable to help us determine when our buffer is going to run out of room and needs resizing.
`private byte[]`	`decodeTable`	Decode table to use.
`private static byte[]`	`ENCODE_TABLE`	This array is a lookup table that translates 5-bit positive integer index values into their "Base32 Alphabet" equivalents as specified in Table 3 of RFC 4648.
`private int`	`encodeSize`	Convenience variable to help us determine when our buffer is going to run out of room and needs resizing.
`private byte[]`	`encodeTable`	Encode table to use.
`private static byte[]`	`HEX_DECODE_TABLE`	This array is a lookup table that translates Unicode characters drawn from the "Base32 Hex Alphabet" (as specified in Table 4 of RFC 4648) into their 5-bit positive integer equivalents.
`private static byte[]`	`HEX_ENCODE_TABLE`	This array is a lookup table that translates 5-bit positive integer index values into their "Base32 Hex Alphabet" equivalents as specified in Table 4 of RFC 4648.
`private byte[]`	`lineSeparator`	Line separator for encoding.
`private static int`	`MASK_5BITS`	Mask used to extract 5 bits, used when encoding Base32 bytes

Fields inherited from class org.apache.commons.codec.binary.BaseNCodec
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 pad)`	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 pad)`	Creates a Base32 / Base32 Hex codec used for decoding and encoding.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`(package private) void`	`decode(byte[] in, int inPos, int inAvail, BaseNCodec.Context context)`	Decodes all of the provided data, starting at inPos, for inAvail bytes.
`(package private) void`	`encode(byte[] in, 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.
`private void`	`validateCharacter(int numBits, BaseNCodec.Context context)`	Validates whether the character is possible in the context of the set of possible base 32 values.

Methods inherited from class org.apache.commons.codec.binary.BaseNCodec
available, containsAlphabetOrPad, decode, decode, decode, encode, encode, encode, encodeAsString, encodeToString, ensureBufferSize, getDefaultBufferSize, getEncodedLength, hasData, isInAlphabet, isInAlphabet, isWhiteSpace, readResults

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - BITS_PER_ENCODED_BYTE
```
private static final int BITS_PER_ENCODED_BYTE
```
    BASE32 characters are 5 bits in length. They are formed by taking a block of five octets to form a 40-bit string, which is converted into eight BASE32 characters.
    
    See Also:
    
    Constant Field Values
  - BYTES_PER_ENCODED_BLOCK
```
private static final int BYTES_PER_ENCODED_BLOCK
```
    See Also:
    
    Constant Field Values
  - BYTES_PER_UNENCODED_BLOCK
```
private static final int BYTES_PER_UNENCODED_BLOCK
```
    See Also:
    
    Constant Field Values
  - CHUNK_SEPARATOR
```
private static final byte[] CHUNK_SEPARATOR
```
    Chunk separator per RFC 2045 section 2.1.
    
    See Also:
    
    RFC 2045 section 2.1
  - DECODE_TABLE
```
private static final byte[] DECODE_TABLE
```
    This array is a lookup table that translates Unicode characters drawn from the "Base32 Alphabet" (as specified in Table 3 of RFC 4648) into their 5-bit positive integer equivalents. Characters that are not in the Base32 alphabet but fall within the bounds of the array are translated to -1.
  - ENCODE_TABLE
```
private static final byte[] ENCODE_TABLE
```
    This array is a lookup table that translates 5-bit positive integer index values into their "Base32 Alphabet" equivalents as specified in Table 3 of RFC 4648.
  - HEX_DECODE_TABLE
```
private static final byte[] HEX_DECODE_TABLE
```
    This array is a lookup table that translates Unicode characters drawn from the "Base32 Hex Alphabet" (as specified in Table 4 of RFC 4648) into their 5-bit positive integer equivalents. Characters that are not in the Base32 Hex alphabet but fall within the bounds of the array are translated to -1.
  - HEX_ENCODE_TABLE
```
private static final byte[] HEX_ENCODE_TABLE
```
    This array is a lookup table that translates 5-bit positive integer index values into their "Base32 Hex Alphabet" equivalents as specified in Table 4 of RFC 4648.
  - MASK_5BITS
```
private static final int MASK_5BITS
```
    Mask used to extract 5 bits, used when encoding Base32 bytes
    
    See Also:
    
    Constant Field Values
  - decodeSize
```
private final int decodeSize
```
    Convenience variable to help us determine when our buffer is going to run out of room and needs resizing. decodeSize = BYTES_PER_ENCODED_BLOCK - 1 + lineSeparator.length;
  - decodeTable
```
private final byte[] decodeTable
```
    Decode table to use.
  - encodeSize
```
private final int encodeSize
```
    Convenience variable to help us determine when our buffer is going to run out of room and needs resizing. encodeSize = BYTES_PER_ENCODED_BLOCK + lineSeparator.length;
  - encodeTable
```
private final byte[] encodeTable
```
    Encode table to use.
  - lineSeparator
```
private final byte[] lineSeparator
```
    Line separator for encoding. Not used when decoding. Only used if lineLength > 0.
- 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(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(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 pad)
```
    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
    
    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:
    
    java.lang.IllegalArgumentException - The provided lineSeparator included some Base32 characters. That's not going to work!
  - 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:
    
    java.lang.IllegalArgumentException - The provided lineSeparator included some Base32 characters. That's not going to work! Or the lineLength > 0 and lineSeparator is null.
  - Base32
```
public Base32(int lineLength,
              byte[] lineSeparator,
              boolean useHex,
              byte pad)
```
    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
    
    pad - byte used as padding byte.
    
    Throws:
    
    java.lang.IllegalArgumentException - The provided lineSeparator included some Base32 characters. That's not going to work! Or the lineLength > 0 and lineSeparator is null.
- Method Detail
  - decode
```
void decode(byte[] in,
            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.
    
    Specified by:
    
    decode in class BaseNCodec
    
    Parameters:
    
    in - 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 Output is written to BaseNCodec.Context.buffer as 8-bit octets, using BaseNCodec.Context.pos as the buffer position
  - encode
```
void encode(byte[] in,
            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:
    
    in - 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.
  - validateCharacter
```
private void validateCharacter(int numBits,
                               BaseNCodec.Context context)
```
    Validates whether the character is possible in the context of the set of possible base 32 values.
    
    Parameters:
    
    numBits - number of least significant bits to check
    
    context - the context to be used
    
    Throws:
    
    java.lang.IllegalArgumentException - if the bits being checked contain any non-zero value

Class Base32

Nested Class Summary

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

Field Summary

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

Constructor Summary

Method Summary

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

Methods inherited from class java.lang.Object

Field Detail

BITS_PER_ENCODED_BYTE

BYTES_PER_ENCODED_BLOCK

BYTES_PER_UNENCODED_BLOCK

CHUNK_SEPARATOR

DECODE_TABLE

ENCODE_TABLE

HEX_DECODE_TABLE

HEX_ENCODE_TABLE

MASK_5BITS

decodeSize

decodeTable

encodeSize

encodeTable

lineSeparator

Constructor Detail

Base32

Base32

Base32

Base32

Base32

Base32

Base32

Base32

Method Detail

decode

encode

isInAlphabet

validateCharacter