org.apache.shiro.codec

Class Hex

java.lang.Object

org.apache.shiro.codec.Hex

public class Hex
extends Object

Hexadecimal encoder and decoder.

This class was borrowed from Apache Commons Codec SVN repository (rev. 560660) with modifications to enable Hex conversion without a full dependency on Commons Codec. We didn't want to reinvent the wheel of great work they've done, but also didn't want to force every Shiro user to depend on the commons-codec.jar

As per the Apache 2.0 license, the original copyright notice and all author and copyright information have remained in tact.

Since:

0.9

See Also:

Wikipedia: Hexadecimal

Constructor Summary

Constructors

Constructor and Description
Hex()

Method Summary

Modifier and Type	Method and Description
static byte[]	decode(byte[] array) Converts an array of character bytes representing hexadecimal values into an array of bytes of those same values.
static byte[]	decode(char[] data) Converts an array of characters representing hexadecimal values into an array of bytes of those same values.
static byte[]	decode(String hex) Converts the specified Hex-encoded String into a raw byte array.
static char[]	encode(byte[] data) Converts an array of bytes into an array of characters representing the hexadecimal values of each byte in order.
static String	encodeToString(byte[] bytes) Encodes the specified byte array to a character array and then returns that character array as a String.
protected static int	toDigit(char ch, int index) Converts a hexadecimal character to an integer.

Methods inherited from class java.lang.Object

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

Constructor Detail

Hex

public Hex()

Method Detail

encodeToString

public static String encodeToString(byte[] bytes)

Encodes the specified byte array to a character array and then returns that character array as a String.

Parameters:

bytes - the byte array to Hex-encode.

Returns:

A String representation of the resultant hex-encoded char array.

encode

public static char[] encode(byte[] data)

Converts an array of bytes into an array of characters representing the hexadecimal values of each byte in order. The returned array will be double the length of the passed array, as it takes two characters to represent any given byte.

Parameters:

data - byte[] to convert to Hex characters

Returns:

A char[] containing hexadecimal characters

decode

public static byte[] decode(byte[] array)
                     throws IllegalArgumentException

Converts an array of character bytes representing hexadecimal values into an array of bytes of those same values. The returned array will be half the length of the passed array, as it takes two characters to represent any given byte. An exception is thrown if the passed char array has an odd number of elements.

Parameters:

array - An array of character bytes containing hexadecimal digits

Returns:

A byte array containing binary data decoded from the supplied byte array (representing characters).

Throws:

IllegalArgumentException - Thrown if an odd number of characters is supplied to this function

See Also:

decode(char[])

decode

public static byte[] decode(String hex)

Converts the specified Hex-encoded String into a raw byte array. This is a convenience method that merely delegates to decode(char[]) using the argument's hex.toCharArray() value.

Parameters:

hex - a Hex-encoded String.

Returns:

A byte array containing binary data decoded from the supplied String's char array.

decode

public static byte[] decode(char[] data)
                     throws IllegalArgumentException

Converts an array of characters representing hexadecimal values into an array of bytes of those same values. The returned array will be half the length of the passed array, as it takes two characters to represent any given byte. An exception is thrown if the passed char array has an odd number of elements.

Parameters:

data - An array of characters containing hexadecimal digits

Returns:

A byte array containing binary data decoded from the supplied char array.

Throws:

IllegalArgumentException - if an odd number or illegal of characters is supplied

toDigit

protected static int toDigit(char ch,
                             int index)
                      throws IllegalArgumentException

Converts a hexadecimal character to an integer.

Parameters:

ch - A character to convert to an integer digit

index - The index of the character in the source

Returns:

An integer

Throws:

IllegalArgumentException - if ch is an illegal hex character