/* * CVS identifier: * * $Id: ArrayUtil.java,v 1.1.1.1 2002/07/22 09:26:53 grosbois Exp $ * * Class:                   ArrayUtil * * Description:             Utillities for arrays. * * * * COPYRIGHT: *  * This software module was originally developed by Rapha雔 Grosbois and * Diego Santa Cruz (Swiss Federal Institute of Technology-EPFL); Joel * Askel鰂 (Ericsson Radio Systems AB); and Bertrand Berthelot, David * Bouchard, F閘ix Henry, Gerard Mozelle and Patrice Onno (Canon Research * Centre France S.A) in the course of development of the JPEG2000 * standard as specified by ISO/IEC 15444 (JPEG 2000 Standard). This * software module is an implementation of a part of the JPEG 2000 * Standard. Swiss Federal Institute of Technology-EPFL, Ericsson Radio * Systems AB and Canon Research Centre France S.A (collectively JJ2000 * Partners) agree not to assert against ISO/IEC and users of the JPEG * 2000 Standard (Users) any of their rights under the copyright, not * including other intellectual property rights, for this software module * with respect to the usage by ISO/IEC and Users of this software module * or modifications thereof for use in hardware or software products * claiming conformance to the JPEG 2000 Standard. Those intending to use * this software module in hardware or software products are advised that * their use may infringe existing patents. The original developers of * this software module, JJ2000 Partners and ISO/IEC assume no liability * for use of this software module or modifications thereof. No license * or right to this software module is granted for non JPEG 2000 Standard * conforming products. JJ2000 Partners have full right to use this * software module for his/her own purpose, assign or donate this * software module to any third party and to inhibit third parties from * using this software module for non JPEG 2000 Standard conforming * products. This copyright notice must be included in all copies or * derivative works of this software module. *  * Copyright (c) 1999/2000 JJ2000 Partners. *  *  *  */package jj2000.j2k.util;/** * This class contains a colleaction of utility static methods for arrays. * */public class ArrayUtil {    /** The maximum array size to do element by element copying, larger     * arrays are copyied in a n optimized way. */    public static final int MAX_EL_COPYING = 8;    /** The number of elements to copy initially in an optimized array copy */    public static final int INIT_EL_COPYING = 4;    /**     * Reinitializes an int array to the given value in an optimized way. If     * the length of the array is less than MAX_EL_COPYING, then the array     * is set element by element in the normal way, otherwise the first     * INIT_EL_COPYING elements are set element by element and then     * System.arraycopy is used to set the other parts of the array.     *     * @param arr The array to set.     *     * @param val The value to set the array to.     *     *     * */    public static void intArraySet(int arr[], int val) {        int i,len,len2;                len = arr.length;        // Set array to 'val' in an optimized way        if (len < MAX_EL_COPYING) {             // Not worth doing optimized way            for (i=len-1; i>=0; i--) { // Set elements                arr[i] = val;            }        }        else { // Do in optimized way            len2 = len>>1;            for (i=0; i<INIT_EL_COPYING; i++) { // Set first elements                arr[i] = val;            }            for (; i <= len2 ; i<<=1) {                // Copy values doubling size each time                System.arraycopy(arr,0,arr,i,i);            }            if (i < len) { // Copy values to end                System.arraycopy(arr,0,arr,i,len-i);            }        }    }    /**     * Reinitializes a byte array to the given value in an optimized way. If     * the length of the array is less than MAX_EL_COPYING, then the array     * is set element by element in the normal way, otherwise the first     * INIT_EL_COPYING elements are set element by element and then     * System.arraycopy is used to set the other parts of the array.     *     * @param arr The array to set.     *     * @param val The value to set the array to.     *     *     * */    public static void byteArraySet(byte arr[], byte val) {        int i,len,len2;                len = arr.length;        // Set array to 'val' in an optimized way        if (len < MAX_EL_COPYING) {             // Not worth doing optimized way            for (i=len-1; i>=0; i--) { // Set elements                arr[i] = val;            }        }        else { // Do in optimized way            len2 = len>>1;            for (i=0; i<INIT_EL_COPYING; i++) { // Set first elements                arr[i] = val;            }            for (; i <= len2 ; i<<=1) {                // Copy values doubling size each time                System.arraycopy(arr,0,arr,i,i);            }            if (i < len) { // Copy values to end                System.arraycopy(arr,0,arr,i,len-i);            }        }    }}