001    /* EVolve - an Extensible Software Visualization Framework
002     * Copyright (C) 2001-2002 Qin Wang
003     *
004     * This library is free software; you can redistribute it and/or
005     * modify it under the terms of the GNU Library General Public
006     * License as published by the Free Software Foundation; either
007     * version 2 of the License, or (at your option) any later version.
008     *
009     * This library is distributed in the hope that it will be useful,
010     * but WITHOUT ANY WARRANTY; without even the implied warranty of
011     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
012     * Library General Public License for more details.
013     *
014     * You should have received a copy of the GNU Library General Public
015     * License along with this library; if not, write to the
016     * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
017     * Boston, MA 02111-1307, USA.
018     */
019    
020    /*
021     * EVolve is distributed at http://www.sable.mcgill.ca/EVolve/
022     */
023    
024    package EVolve.util;
025    
026    import EVolve.data.*;
027    
028    
029    public class Sorter implements Cloneable{
030        private int[] source, target;
031        private EntityComparator comparator;
032    
033        public Sorter(Entity[] array, EntityComparator comparator) {
034            this.comparator = comparator;
035    
036            int size = array.length;
037            Entity[] arr = new Entity[size];
038    
039            source = new int[size];
040            target = new int[size];
041    
042            for (int i = 0; i < size; i++) {
043                arr[i] = array[i];
044                source[i] = i;
045            }
046    
047            mergesort(arr);
048    
049            for (int i = 0; i < size; i++) {
050                target[source[i]] = i;
051            }
052        }
053    
054        public int getTarget(int source) {
055            if ((source >= target.length) || (source < 0))
056                return -1;
057            else
058                return target[source];
059        }
060    
061        public int getSource(int target) {
062            if ((target >= source.length) || (target < 0))
063                return -1;
064            else
065                return source[target];
066        }
067    
068        private void mergesort(Entity[] array) {
069            Entity[] temp = new Entity[array.length];
070            int[] tempSource = new int[array.length];
071    
072            int step = 1;
073            while (step<array.length) {
074                int L1=0, L2, H1, H2, k=0;
075                while (L1+step<array.length) {
076                    L2 = L1 + step;
077                    H1 = L2 - 1;
078                    if (L2+step-1>=array.length)
079                        H2 = array.length-1;
080                    else
081                        H2 = L2+step-1;
082                    k = mergepass(temp,array,tempSource,L1,L2,H1,H2,k);
083                    L1 = H2 + 1;
084                }
085                int i = L1;
086                while ((k < array.length)&&(i<array.length)) {
087                    temp[k] = array[i];
088                    tempSource[k] = source[i];
089                    i++; k++;
090                }
091                for (i=0; i<array.length; i++) {
092                    array[i] = temp[i];
093                    source[i] = tempSource[i];
094                }
095                step = step * 2;
096            }
097        }
098    
099        private int mergepass(Entity[] temp, Entity[] array, int[] tempSource, int L1, int L2, int H1, int H2, int k) {
100            int i = L1, j = L2;
101            while ((i<=H1)&&(j<=H2)) {
102                if (comparator.compare(array[i], array[j]) < 0) {
103                    tempSource[k] = source[i];
104                    temp[k] = array[i];
105                    i++;
106                } else {
107                    tempSource[k] = source[j];
108                    temp[k] = array[j];
109                    j++;
110                }
111                k++;
112            }
113            while (i<=H1) {
114                temp[k] = array[i];
115                tempSource[k] = source[i];
116                i++; k++;
117            }
118            while (j<=H2) {
119                temp[k] = array[j];
120                tempSource[k] = source[j];
121                j++; k++;
122            }
123            return k;
124        }
125    
126        public Object clone() {
127            Sorter o = null;
128            try {
129                o = (Sorter)super.clone();
130            } catch (CloneNotSupportedException e) {
131                e.printStackTrace();
132            }
133    
134            o.source = new int[source.length];
135            for (int i=0; i<source.length; i++)
136                o.source[i] = source[i];
137    
138            o.target = new int[target.length];
139            for (int i=0; i<target.length; i++)
140                o.target[i] = target[i];
141    
142            o.comparator = (EntityComparator)comparator.clone();
143            return o;
144        }
145    }