cryptix.util.core

Class ArrayUtil


public class ArrayUtil
extends java.lang.Object

Static methods for converting between arrays of various types, for clearing all or part of a byte array, and for comparing two byte arrays.

Copyright © 1997 Systemics Ltd on behalf of the Cryptix Development Team.
All rights reserved.

$Revision: 1.6 $

Authors:
Raif Naffah
David Hopwood
Ian Brown
Since:
Cryptix 2.2.2

Method Summary

static boolean
areEqual(byte[] a, byte[] b)
Compares two byte arrays for equality.
static boolean
areEqual(int[] a, int[] b)
Compares two int arrays for equality.
static void
clear(byte[] buf)
Clears a byte array to all-zeroes.
static void
clear(byte[] buf, int offset, int length)
Clears length bytes of a byte array to zeroes, starting at offset.
static int
compared(byte[] a, byte[] b, boolean msbFirst)
static boolean
isText(byte[] buffer)
static byte[]
toBytes(int n)
Returns a 4-byte array built from an int.
static byte[]
toBytes(short[] array)
static byte[]
toBytes(short[] array, int offset, int length)
Returns a byte array built from a short array.
static int
toInt(short s0, short s1)
Returns an int built from two shorts.
static short
toShort(byte b0, byte b1)
Returns a short built from two bytes.
static short[]
toShorts(byte[] array)
static short[]
toShorts(byte[] array, int offset, int length)
Returns a short array built from a byte array.

Method Details

areEqual

public static boolean areEqual(byte[] a,
                               byte[] b)
Compares two byte arrays for equality.
Returns:
true if the arrays have identical contents

areEqual

public static boolean areEqual(int[] a,
                               int[] b)
Compares two int arrays for equality.
Returns:
true if the arrays have identical contents

clear

public static void clear(byte[] buf)
Clears a byte array to all-zeroes.

clear

public static void clear(byte[] buf,
                         int offset,
                         int length)
Clears length bytes of a byte array to zeroes, starting at offset.

compared

public static int compared(byte[] a,
                           byte[] b,
                           boolean msbFirst)

isText

public static boolean isText(byte[] buffer)
Returns:
true If the data in the byte array consists of just text.

toBytes

public static byte[] toBytes(int n)
Returns a 4-byte array built from an int. The int's MSB is first (big-endian order).

toBytes

public static byte[] toBytes(short[] array)

toBytes

public static byte[] toBytes(short[] array,
                             int offset,
                             int length)
Returns a byte array built from a short array. Each short is broken into 2 bytes with the short's MSB first (big-endian order).

If offset and length are omitted, the whole array is used.


toInt

public static int toInt(short s0,
                        short s1)
Returns an int built from two shorts.
Parameters:
s0 - the least significant short
s1 - the most significant short

toShort

public static short toShort(byte b0,
                            byte b1)
Returns a short built from two bytes.
Parameters:
b0 - the least significant byte
b1 - the most significant byte

toShorts

public static short[] toShorts(byte[] array)

toShorts

public static short[] toShorts(byte[] array,
                               int offset,
                               int length)
Returns a short array built from a byte array. Each 2 bytes form a short with the first byte as the short's MSB (big-endian order).

If offset and length are omitted, the whole array is used.