com.cloudhopper.commons.util

Class HexUtil

java.lang.Object

com.cloudhopper.commons.util.HexUtil

public class HexUtil
extends Object

Utility class for encoding or decoding objects to a hexidecimal format.

Author:

joelauer (twitter: @jjlauer or http://twitter.com/jjlauer)

Field Summary

Fields

Modifier and Type	Field and Description
static char[]	HEX_TABLE

Constructor Summary

Constructors

Constructor and Description
HexUtil()

Method Summary

Methods

Modifier and Type	Method and Description
static void	appendHexString(StringBuilder buffer, byte value) Appends 2 characters to a StringBuilder with the byte in a "Big Endian" hexidecimal format.
static void	appendHexString(StringBuilder buffer, byte[] bytes) Appends a byte array to a StringBuilder with each byte in a "Big Endian" hexidecimal format.
static void	appendHexString(StringBuilder buffer, byte[] bytes, int offset, int length) Appends a byte array to a StringBuilder with each byte in a "Big Endian" hexidecimal format.
static void	appendHexString(StringBuilder buffer, int value) Appends 8 characters to a StringBuilder with the int in a "Big Endian" hexidecimal format.
static void	appendHexString(StringBuilder buffer, long value) Appends 16 characters to a StringBuilder with the long in a "Big Endian" hexidecimal format.
static void	appendHexString(StringBuilder buffer, short value) Appends 4 characters to a StringBuilder with the short in a "Big Endian" hexidecimal format.
static int	hexCharToIntValue(char c) Converts a hexidecimal character such as '0' or 'A' or 'a' to its integer value such as 0 or 10.
static byte[]	toByteArray(CharSequence hexString) Creates a byte array from a CharSequence (String, StringBuilder, etc.) containing only valid hexidecimal formatted characters.
static byte[]	toByteArray(CharSequence hexString, int offset, int length) Creates a byte array from a CharSequence (String, StringBuilder, etc.) containing only valid hexidecimal formatted characters.
static String	toHexString(byte value) Creates a 2 character hex String from a byte with the byte in a "Big Endian" hexidecimal format.
static String	toHexString(byte[] bytes) Creates a String from a byte array with each byte in a "Big Endian" hexidecimal format.
static String	toHexString(byte[] bytes, int offset, int length) Creates a String from a byte array with each byte in a "Big Endian" hexidecimal format.
static String	toHexString(int value) Creates an 8 character hex String from an int twith the int in a "Big Endian" hexidecimal format.
static String	toHexString(long value) Creates a 16 character hex String from a long with the long in a "Big Endian" hexidecimal format.
static String	toHexString(short value) Creates a 4 character hex String from a short with the short in a "Big Endian" hexidecimal format.

Methods inherited from class java.lang.Object

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

Field Detail

HEX_TABLE

public static char[] HEX_TABLE

Constructor Detail

HexUtil

public HexUtil()

Method Detail

toHexString

public static String toHexString(byte[] bytes)

Creates a String from a byte array with each byte in a "Big Endian" hexidecimal format. For example, a byte 0x34 will return a String "34". A byte array of { 0x34, 035 } would return "3435".

Parameters:

buffer - The StringBuilder the byte array in hexidecimal format will be appended to. If the buffer is null, this method will throw a NullPointerException.

bytes - The byte array that will be converted to a hexidecimal String. If the byte array is null, this method will append nothing (a noop)

toHexString

public static String toHexString(byte[] bytes,
                 int offset,
                 int length)

Creates a String from a byte array with each byte in a "Big Endian" hexidecimal format. For example, a byte 0x34 will return a String "34". A byte array of { 0x34, 035 } would return "3435".

Parameters:

buffer - The StringBuilder the byte array in hexidecimal format will be appended to. If the buffer is null, this method will throw a NullPointerException.

bytes - The byte array that will be converted to a hexidecimal String. If the byte array is null, this method will append nothing (a noop)

offset - The offset in the byte array to start from. If the offset or length combination is invalid, this method will throw an IllegalArgumentException.

length - The length (from the offset) to conver the bytes. If the offset or length combination is invalid, this method will throw an IllegalArgumentException.

appendHexString

public static void appendHexString(StringBuilder buffer,
                   byte[] bytes)

Appends a byte array to a StringBuilder with each byte in a "Big Endian" hexidecimal format. For example, a byte 0x34 will be appended as a String in format "34". A byte array of { 0x34, 035 } would append "3435".

Parameters:

buffer - The StringBuilder the byte array in hexidecimal format will be appended to. If the buffer is null, this method will throw a NullPointerException.

bytes - The byte array that will be converted to a hexidecimal String. If the byte array is null, this method will append nothing (a noop)

appendHexString

public static void appendHexString(StringBuilder buffer,
                   byte[] bytes,
                   int offset,
                   int length)

Appends a byte array to a StringBuilder with each byte in a "Big Endian" hexidecimal format. For example, a byte 0x34 will be appended as a String in format "34". A byte array of { 0x34, 035 } would append "3435".

Parameters:

buffer - The StringBuilder the byte array in hexidecimal format will be appended to. If the buffer is null, this method will throw a NullPointerException.

bytes - The byte array that will be converted to a hexidecimal String. If the byte array is null, this method will append nothing (a noop)

offset - The offset in the byte array to start from. If the offset or length combination is invalid, this method will throw an IllegalArgumentException.

length - The length (from the offset) to conver the bytes. If the offset or length combination is invalid, this method will throw an IllegalArgumentException.

toHexString

public static String toHexString(byte value)

Creates a 2 character hex String from a byte with the byte in a "Big Endian" hexidecimal format. For example, a byte 0x34 will be returned as a String in format "34". A byte of value 0 will be returned as "00".

Parameters:

value - The byte value that will be converted to a hexidecimal String.

appendHexString

public static void appendHexString(StringBuilder buffer,
                   byte value)

Appends 2 characters to a StringBuilder with the byte in a "Big Endian" hexidecimal format. For example, a byte 0x34 will be appended as a String in format "34". A byte of value 0 will be appended as "00".

Parameters:

buffer - The StringBuilder the byte value in hexidecimal format will be appended to. If the buffer is null, this method will throw a NullPointerException.

value - The byte value that will be converted to a hexidecimal String.

toHexString

public static String toHexString(short value)

Creates a 4 character hex String from a short with the short in a "Big Endian" hexidecimal format. For example, a short 0x1234 will be returned as a String in format "1234". A short of value 0 will be returned as "0000".

Parameters:

value - The short value that will be converted to a hexidecimal String.

appendHexString

public static void appendHexString(StringBuilder buffer,
                   short value)

Appends 4 characters to a StringBuilder with the short in a "Big Endian" hexidecimal format. For example, a short 0x1234 will be appended as a String in format "1234". A short of value 0 will be appended as "0000".

Parameters:

buffer - The StringBuilder the short value in hexidecimal format will be appended to. If the buffer is null, this method will throw a NullPointerException.

value - The short value that will be converted to a hexidecimal String.

toHexString

public static String toHexString(int value)

Creates an 8 character hex String from an int twith the int in a "Big Endian" hexidecimal format. For example, an int 0xFFAA1234 will be returned as a String in format "FFAA1234". A int of value 0 will be returned as "00000000".

Parameters:

value - The int value that will be converted to a hexidecimal String.

appendHexString

public static void appendHexString(StringBuilder buffer,
                   int value)

Appends 8 characters to a StringBuilder with the int in a "Big Endian" hexidecimal format. For example, a int 0xFFAA1234 will be appended as a String in format "FFAA1234". A int of value 0 will be appended as "00000000".

Parameters:

buffer - The StringBuilder the int value in hexidecimal format will be appended to. If the buffer is null, this method will throw a NullPointerException.

value - The int value that will be converted to a hexidecimal String.

toHexString

public static String toHexString(long value)

Creates a 16 character hex String from a long with the long in a "Big Endian" hexidecimal format. For example, a long 0xAABBCCDDEE123456 will be returned as a String in format "AABBCCDDEE123456". A long of value 0 will be returned as "0000000000000000".

Parameters:

value - The long value that will be converted to a hexidecimal String.

appendHexString

public static void appendHexString(StringBuilder buffer,
                   long value)

Appends 16 characters to a StringBuilder with the long in a "Big Endian" hexidecimal format. For example, a long 0xAABBCCDDEE123456 will be appended as a String in format "AABBCCDDEE123456". A long of value 0 will be appended as "0000000000000000".

Parameters:

buffer - The StringBuilder the long value in hexidecimal format will be appended to. If the buffer is null, this method will throw a NullPointerException.

value - The long value that will be converted to a hexidecimal String.

hexCharToIntValue

public static int hexCharToIntValue(char c)

Converts a hexidecimal character such as '0' or 'A' or 'a' to its integer value such as 0 or 10. Used to decode hexidecimal Strings to integer values.

Parameters:

c - The hexidecimal character

Returns:

The integer value the character represents

Throws:

IllegalArgumentException - Thrown if a character that does not represent a hexidecimal character is used.

toByteArray

public static byte[] toByteArray(CharSequence hexString)

Creates a byte array from a CharSequence (String, StringBuilder, etc.) containing only valid hexidecimal formatted characters. Each grouping of 2 characters represent a byte in "Big Endian" format. The hex CharSequence must be an even length of characters. For example, a String of "1234" would return the byte array { 0x12, 0x34 }.

Parameters:

hexString - The String, StringBuilder, etc. that contains the sequence of hexidecimal character values.

Returns:

A new byte array representing the sequence of bytes created from the sequence of hexidecimal characters. If the hexString is null, then this method will return null.

toByteArray

public static byte[] toByteArray(CharSequence hexString,
                 int offset,
                 int length)

Creates a byte array from a CharSequence (String, StringBuilder, etc.) containing only valid hexidecimal formatted characters. Each grouping of 2 characters represent a byte in "Big Endian" format. The hex CharSequence must be an even length of characters. For example, a String of "1234" would return the byte array { 0x12, 0x34 }.

Parameters:

hexString - The String, StringBuilder, etc. that contains the sequence of hexidecimal character values.

offset - The offset within the sequence to start from. If the offset is invalid, will cause an IllegalArgumentException.

length - The length from the offset to convert. If the length is invalid, will cause an IllegalArgumentException.

Returns:

A new byte array representing the sequence of bytes created from the sequence of hexidecimal characters. If the hexString is null, then this method will return null.