java.lang.Object
- org.apache.commons.codec.binary.BaseNCodec
- - org.apache.commons.codec.binary.Base16

All Implemented Interfaces:

BinaryDecoder, BinaryEncoder, Decoder, Encoder
```
public class Base16
extends BaseNCodec
```
Provides Base16 encoding and decoding.
This class is thread-safe.

This implementation strictly follows RFC 4648, and as such unlike the Base32 and Base64 implementations, it does not ignore invalid alphabet characters or whitespace, neither does it offer chunking or padding characters.

The only additional feature above those specified in RFC 4648 is support for working with a lower-case alphabet in addition to the default upper-case alphabet.

Since:

1.15

See Also:

RFC 4648 - 8. Base 16 Encoding

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`	BASE16 characters are 4 bits in length.
`private static int`	`BYTES_PER_ENCODED_BLOCK`
`private static int`	`BYTES_PER_UNENCODED_BLOCK`
`private byte[]`	`decodeTable`	Decode table to use.
`private byte[]`	`encodeTable`	Encode table to use.
`private static byte[]`	`LOWER_CASE_DECODE_TABLE`	This array is a lookup table that translates Unicode characters drawn from the a lower-case "Base16 Alphabet" into their 4-bit positive integer equivalents.
`private static byte[]`	`LOWER_CASE_ENCODE_TABLE`	This array is a lookup table that translates 4-bit positive integer index values into their "Base16 Alphabet" lower-case equivalents.
`private static int`	`MASK_4BITS`	Mask used to extract 4 bits, used when decoding character.
`private static byte[]`	`UPPER_CASE_DECODE_TABLE`	This array is a lookup table that translates Unicode characters drawn from the "Base16 Alphabet" (as specified in Table 5 of RFC 4648) into their 4-bit positive integer equivalents.
`private static byte[]`	`UPPER_CASE_ENCODE_TABLE`	This array is a lookup table that translates 4-bit positive integer index values into their "Base16 Alphabet" equivalents as specified in Table 5 of RFC 4648.

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
`Base16()`	Creates a Base16 codec used for decoding and encoding.
`Base16(boolean lowerCase)`	Creates a Base16 codec used for decoding and encoding.
`Base16(boolean lowerCase, CodecPolicy decodingPolicy)`	Creates a Base16 codec used for decoding and encoding.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`(package private) void`	`decode(byte[] data, int offset, int length, BaseNCodec.Context context)`
`private int`	`decodeOctet(byte octet)`
`(package private) void`	`encode(byte[] data, int offset, int length, BaseNCodec.Context context)`
`boolean`	`isInAlphabet(byte octet)`	Returns whether or not the `octet` is in the Base16 alphabet.
`private void`	`validateTrailingCharacter()`	Validates whether decoding allows an entire final trailing character that cannot be used for a complete byte.

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

- Field Detail
  - BITS_PER_ENCODED_BYTE
```
private static final int BITS_PER_ENCODED_BYTE
```
    BASE16 characters are 4 bits in length. They are formed by taking an 8-bit group, which is converted into two BASE16 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
  - UPPER_CASE_DECODE_TABLE
```
private static final byte[] UPPER_CASE_DECODE_TABLE
```
    This array is a lookup table that translates Unicode characters drawn from the "Base16 Alphabet" (as specified in Table 5 of RFC 4648) into their 4-bit positive integer equivalents. Characters that are not in the Base16 alphabet but fall within the bounds of the array are translated to -1.
  - UPPER_CASE_ENCODE_TABLE
```
private static final byte[] UPPER_CASE_ENCODE_TABLE
```
    This array is a lookup table that translates 4-bit positive integer index values into their "Base16 Alphabet" equivalents as specified in Table 5 of RFC 4648.
  - LOWER_CASE_DECODE_TABLE
```
private static final byte[] LOWER_CASE_DECODE_TABLE
```
    This array is a lookup table that translates Unicode characters drawn from the a lower-case "Base16 Alphabet" into their 4-bit positive integer equivalents. Characters that are not in the Base16 alphabet but fall within the bounds of the array are translated to -1.
  - LOWER_CASE_ENCODE_TABLE
```
private static final byte[] LOWER_CASE_ENCODE_TABLE
```
    This array is a lookup table that translates 4-bit positive integer index values into their "Base16 Alphabet" lower-case equivalents.
  - MASK_4BITS
```
private static final int MASK_4BITS
```
    Mask used to extract 4 bits, used when decoding character.
    
    See Also:
    
    Constant Field Values
  - decodeTable
```
private final byte[] decodeTable
```
    Decode table to use.
  - encodeTable
```
private final byte[] encodeTable
```
    Encode table to use.
- Constructor Detail
  - Base16
```
public Base16()
```
    Creates a Base16 codec used for decoding and encoding.
  - Base16
```
public Base16(boolean lowerCase)
```
    Creates a Base16 codec used for decoding and encoding.
    
    Parameters:
    
    lowerCase - if true then use a lower-case Base16 alphabet.
  - Base16
```
public Base16(boolean lowerCase,
              CodecPolicy decodingPolicy)
```
    Creates a Base16 codec used for decoding and encoding.
    
    Parameters:
    
    lowerCase - if true then use a lower-case Base16 alphabet.
    
    decodingPolicy - Decoding policy.
- Method Detail
  - decode
```
void decode(byte[] data,
            int offset,
            int length,
            BaseNCodec.Context context)
```
    Specified by:
    
    decode in class BaseNCodec
  - decodeOctet
```
private int decodeOctet(byte octet)
```
  - encode
```
void encode(byte[] data,
            int offset,
            int length,
            BaseNCodec.Context context)
```
    Specified by:
    
    encode in class BaseNCodec
  - isInAlphabet
```
public boolean isInAlphabet(byte octet)
```
    Returns whether or not the octet is in the Base16 alphabet.
    
    Specified by:
    
    isInAlphabet in class BaseNCodec
    
    Parameters:
    
    octet - The value to test.
    
    Returns:
    
    true if the value is defined in the the Base16 alphabet false otherwise.
  - validateTrailingCharacter
```
private void validateTrailingCharacter()
```
    Validates whether decoding allows an entire final trailing character that cannot be used for a complete byte.
    
    Throws:
    
    java.lang.IllegalArgumentException - if strict decoding is enabled

Class Base16

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

UPPER_CASE_DECODE_TABLE

UPPER_CASE_ENCODE_TABLE

LOWER_CASE_DECODE_TABLE

LOWER_CASE_ENCODE_TABLE

MASK_4BITS

decodeTable

encodeTable

Constructor Detail

Base16

Base16

Base16

Method Detail

decode

decodeOctet

encode

isInAlphabet

validateTrailingCharacter