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请大家帮我看看我用多线程写的冒泡法，有些错误

rongdf

发贴: 3
积分: 0

于 2005-11-17 00:26

import java.lang.*;

class mySort extends Thread{

  int[] unsort;
  int[] sorted;
  int[] hops = new int[1];
  Semaphore sem;
  //constructor
  protected mySort(int[] ia,int[] oa,int[] ns,Semaphore s){
    unsort = ia;
    sorted = oa;
    hops = ns;
    sem = s;
  }

  public void run(){
    //using Semaphore to control threads
    do {
sem.P();
bubbleSort(unsort,sorted,hops);
sem.V();
} while (true);
  }

  //the bubble sort implementation
  void bubbleSort(int[] numbers, int[] newnumber, int[] times){
  int i, j, temp;
  int length = numbers.length;

  //make a copy of array numbers to array newnumber
  for (i = 0; i <= (length-1); i++){
  newnumber[i] = numbers[i];
  }

  for (i = (length-1); i >= 0; i--){
  for (j = 1; j <= i; j++){
  if (newnumber[j-1] > newnumber[j]){
  temp = newnumber[j-1];
  newnumber[j-1] = newnumber[j];
  newnumber[j] = temp;
  //hops increments by 1 when loop executes once
  hops[0]= hops[0] + 1;
  }
  }
  }
  }
}

class Assignment237{
  static Semaphore sem = new Semaphore(1);

//creat a new object
  public static void pbsort(int [] ia, int [] oa, int [] ns) {
    mySort s[] = new mySort[ia.length-1];

    //start threads based on the length of array to be sorted.
    //e.g.,there are n elements in the array,then start (n-1) threads
      for(int i = 0;i<(ia.length-2);i++){
        s[i] = new mySort(ia,oa,ns,sem);
        s[i].start();
      }
  }
}

class Test extends Assignment237 {

public static void main (String [] args) {
int [] ia = {4, 3, 2, 1};
int [] oa = new int[ia.length];
int [] ns = new int[1];

System.out.print("unsorted = ");
for(int i=0; i<ia.length; i++)
System.out.print(ia[i]+" ");
System.out.println("");

pbsort(ia, oa, ns) ;

System.out.print("sorted = ");
for(int i=0; i<oa.length; i++)
System.out.print(oa[i]+" ");

System.out.println(" hops = "+(ns[0]));
}
}

有2个问题我解决不了
1,不能把相关的array的值传进mySort class下的unsort,sorted,hops这几个变量中。
2，我试着用Semaphore去控制thread，但似乎会导致一个deadlock，我应该用得不怎么正确，各位DX能帮看看如何改进吗？

• 我有一点感想和初学者们同享(原创)

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人气	标题	作者	字数	发贴时间
3317	请大家帮我看看我用多线程写的冒泡法，有些错误	rongdf	2368	2005-11-17 00:26

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