org.jpedal.utils.Sorts Maven / Gradle / Ivy

Go to download
/*
 * ===========================================
 * Java Pdf Extraction Decoding Access Library
 * ===========================================
 *
 * Project Info:  http://www.idrsolutions.com
 * Help section for developers at http://www.idrsolutions.com/support/
 *
 * (C) Copyright 1997-2015 IDRsolutions and Contributors.
 *
 * This file is part of JPedal/JPDF2HTML5
 *
     This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA


 *
 * ---------------
 * Sorts.java
 * ---------------
 */
package org.jpedal.utils;

/**
 * repository for general sorting routines
 * (needs other sort classes adding in)
 * 
This class is NOT part of the API
 */
public class Sorts
{
    
    //////////////////////////////////////////////////////////////////////
    /**
     * quick sort list on 1 value with names as int
     * primary is sorted into ascending order and names is joined to primary.
     * so if primary[i] is moved to primary[j], then names[i] is moved to names[j]
     */
    //#####################################################
    
    private static void sift(final int[] primary, final int[] names, final int left, final int right) {
//		variables for sift moved to reduce initialization
        int currentLeft;
//		variables for sift moved to reduce initialization
        final int primaryTMP;
//	  variables for sift moved to reduce initialization
        final int namesTMP;
//	  variables for sift moved to reduce initialization
        int childL;
        
        //assign left to local
        currentLeft = left;
        //temp store of left item
        primaryTMP = primary[currentLeft];
        //temp store of left item
        namesTMP = names[currentLeft];
        
        //Left child node of currentLeft
        childL = 2*left+1;
        
        
        //Find a[left]'s larger child
        if ((childL0) {
            
            left -= 1;
            
            //go through tree starting with leaves and going up
            sift(primary,names, left, right);
        }
        
        //rearrange heap into a sorted array
        while (right>0) {
            
            //assert: largest unsorted value is at a[0]
            //move largest item to right end
            final int tempA=primary[0];
            final int tempB=names[0];
            primary[0]=primary[right];
            names[0]=names[right];
            primary[right]=tempA;
            names[right]=tempB;
            //assert: a[right..] is sorted
            
            //right is largest and sorted decrement it
            right -= 1;
            
            //get largest value in the tree to the leftMost position
            sift(primary,names, left, right);
        }
        //assert: right==0, therefore a[0..] is all sorted
        
        return names;
    }
    //#####################################################
    /**
     * quick sort list on 2 values with names as int
     */
    public static final int[] quicksort( final int[] primary, final int[] secondary, final int[] names )
    {
        final int items = names.length;
        
        //copy items so we don't sort originals
        final int[] primary_values = new int[items];
        final int[] secondary_values = new int[items];
        for( int i = 0;i < items;i++ )
        {
            primary_values[i] = primary[i];
            secondary_values[i] = secondary[i];
        }
        final int start = 0;
        int i, j, k;
        int temp, temp2;
        int temp_name;
        for( i = start + 1;i < items;i++ )
        {
            temp = primary_values[i];
            temp2 = secondary_values[i];
            temp_name = names[i];
            k = start;
            for( j = i - 1;j >= start;j-- ) {
                if( ( temp < primary_values[j] ) | ( ( temp == primary_values[j] ) & ( temp2 < secondary_values[j] ) ) )
                {
                    primary_values[j + 1] = primary_values[j];
                    secondary_values[j + 1] = secondary_values[j];
                    names[j + 1] = names[j];
                }else{
                    k = j + 1;
                    break;
                }
            }
            primary_values[k] = temp;
            secondary_values[k] = temp2;
            names[k] = temp_name;
        }
        
        //return the sorted list
        return names;
    }
}