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Thread: thread sorting

  1. #1
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    Default thread sorting

    Hello!!!!
    I want your help for this program!!!
    Sorry for my english!

    I want to create a pro that will sort an array[1024*16], i want to have 3 classes one for sortingthread, one for mergingthread and one for the main.

    I wrote the code for sortingthread and mergingthread class but i have problem for the main class

    /**
     *
     * @author fakie
     */
    public class MergingThread extends Thread {
     
        double[] mergedArray;
        double[] A1;
        double[] A2;
     
        public MergingThread(double[] Array1, double[] Array2) {
     
            A1 = Array1;
            A2 = Array2;
            mergedArray = new double[A1.length + A2.length];
     
        }
     
        public double[] getMergedArray() {
            return mergedArray;
        }
     
        @Override
        public void run() {
     
            int i, j, k, m, n;
     
            i = 0;
            j = 0;
            k = 0;
     
            m = A1.length;
            n = A2.length;
     
            while (i < m && j < n) {
     
                if (A1[i] <= A2[j]) {
     
                    mergedArray[k] = A1[i];
                    i++;
                } else {
     
                    mergedArray[k] = A2[j];
                    j++;
                }
                k++;
            }
     
            if (i < m) {
     
                for (int p = i; p < m; p++) {
     
                    mergedArray[k] = A1[p];
                    k++;
                }
            } else {
     
                for (int p = j; p < n; p++) {
     
                    mergedArray[k] = A2[p];
                    k++;
                }
     
            }
            System.out.println("Merged");
            for(k=0;k<8;k++){
            System.out.println(mergedArray[k]);
            }
        }
    }




    /**
     *
     * @author fakie
     */
    public class SortingThread extends Thread {
     
    	double[] unsrtArray, sortedArray;
        private double threadId;
        private double arraySize;
     
        public SortingThread(double[] unsortedArray) {
            unsrtArray = unsortedArray;
            arraySize = unsortedArray.length;
        }
     
        public double[] getSortedArray() {
            return sortedArray;
        }
     
        public void setThreadId(int id) {
            threadId = id;
        }
     
        @Override
        public void run() {
     
            long startTime = System.currentTimeMillis();
     
            int n = unsrtArray.length;
            for (int pass = 1; pass < n; pass++) {
     
                for (int i = 0; i < n - pass; i++) {
                    if (unsrtArray[i] > unsrtArray[i + 1]) {
     
                    	double temp = unsrtArray[i];
                        unsrtArray[i] = unsrtArray[i + 1];
                        unsrtArray[i + 1] = temp;
     
                    }
                }
            }
            sortedArray = unsrtArray;
     
            long endTime = System.currentTimeMillis();
            System.out.println("Unique Thread Number: " + threadId + ", Array Size: "
                    + arraySize + ", Sorting took: " + (endTime - startTime) + "ms");
     
     
        }
    }



    i want to give in main's args the number of threads

    if i want to sort an array[16] and i want 4 threads

    array[0]-array[3]

    array[4]-array[7]

    array[8]-array[11]

    array[12]-array[15]

    the sortingthread will sort the 4 arrays

    and then the mertgingthread array will combine the 4 arrays

    array[0]-array[3]
    ------------------------------mergingthread(1)
    array[4]-array[7]
    -------------------------------------------------------------mergingthread(3)
    array[8]-array[11]
    ------------------------------mergingthread(2)
    array[12]-array[15]

    The mergingthread(3) it will use the function join to wait to finish mergingthread(1) and mergingthread(2)

    i want only the code for soringthread and mergingthread in class main


    Please if you understand my problem help me!!!!!
    Thanks!!!!!!!!!!!!!


  2. #2
    Junior Member
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    Default Re: thread sorting

    import java.util.*;
    import java.util.concurrent.ExecutorService;
    import java.util.concurrent.Executors;
    import java.io.*;
     
    public class FileSorter extends Thread {
    	static int pli=16;
    	private static final int MAX_NUMBER = 10;
    	static double[] a1 = new double[8];
    	static double[] a2 = new double[8];
    	static double[][] array;
    	static int nThreads;
     
    	/**
    	 * @param args
    	 */
    	public static void main(String[] args) throws IOException {
    		nThreads = Integer.parseInt(args[1]);
    		array = new double[nThreads][pli/nThreads];
    		System.out.println(nThreads);
    		Random random = new Random(System.currentTimeMillis());
    		PrintWriter out = new PrintWriter(new FileWriter("numbers.txt"));
    		for(int i = 0; i < pli; i++) {
    			out.println(random.nextInt(MAX_NUMBER));
    			out.flush();
    		}
    		readArray();
     
     
    		for (int i=0;i<nThreads;i++){
    			for (int j=0;j<pli/nThreads;j++){
    				System.out.println(array[i][j]);
    			}
    			System.out.println("");
    		}
     
    		System.out.println("");
     
     
    		SortingThread t[] = new SortingThread[nThreads];       
            for(int i=0; i<nThreads; i++){
                  t[i] = new SortingThread(array[i]);
                  t[i].setThreadId(i);
                  t[i].start();
            }
     
            for(int qq = 0;qq<nThreads;qq++){
            	if(t[qq]!=null){
            		try {
            			t[qq].join();
    				} catch (InterruptedException e) {
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
            	}
            }
     
            for (int i=0;i<nThreads;i++){
    			for (int j=0;j<pli/nThreads;j++){
    				System.out.println(array[i][j]);
    			}
    			System.out.println("");
    		}
    		System.out.println("");
     
     
            MergingThread t2[] = new MergingThread[nThreads-1];    
            /*	for(int j=0; j<nThreads-1; j++){
            		t2[j] = new MergingThread(array[0],array[1]);
            		t2[j].start();
            		i+=unsrtArray.length/2;
            		try {
    					t2[j].join();
    				} catch (InterruptedException e) {
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
     
            	}*/
            t2[0] = new MergingThread(array[0],array[1]);
    		t2[0].start();
    		t2[1] = new MergingThread(array[2],array[3]);
    		t2[1].start();
    		for(int qq = 0;qq<nThreads-2;qq++){
            	if(t2[qq]!=null){
            		try {
            			t2[qq].join();
    				} catch (InterruptedException e) {
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
            	}
            }
    	//	for(int i1=0; i1<16; i1++){
    			a1=t[0].getSortedArray().length[i];
    			a2=t[1].getSortedArray();
    			for (int j=0;j<8;j++){
    				System.out.println(a2);
    			}
    			System.out.println("");
    	//	}
    		t2[2] = new MergingThread(a1,a2);
    		t2[2].start();
     
     
     
    	}
     
     
    	public static double[][] readArray() throws IOException{
    		Reader r = new BufferedReader(new FileReader("numbers.txt"));
    	    StreamTokenizer stok = new StreamTokenizer(r);
    	    stok.parseNumbers();
    	    stok.nextToken();
    	    int i=0;
    	    int j=0;
    	    while (stok.ttype != StreamTokenizer.TT_EOF) {
    	      if (stok.ttype == StreamTokenizer.TT_NUMBER){
    	    	  array[i][j] = stok.nval;
    	    	  j++;
    	    	  if(j==pli/nThreads){
    	    		  i++;
    	    		  j=0;
    	    	  }
    	    	  stok.nextToken();
    	    	  }
    	    }
    		return array;
    	}
     
    }




    can anybody help me?????? plz!!!!!!

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