Question

目标：想要计算访问高优先级和低优先级线程的次数。 //当我编译下面的代码时，＆＃39; h＆＃39;（int h代表高）保持为零，但是＆＃39;（低）增加。

    class Priority implements Runnable {
    int high = 0; 
    int low = 0;
    int count; Thread thrd;
    static boolean stop = false;
    static String currentName;
     Priority(String name) {
      thrd = new Thread(this, name);
      count = 0;
      currentName = name;
     }
     public void run() {
     System.out.println(thrd.getName() + " starting.");
     do {
      count++;

      if(currentName.compareTo(thrd.getName()) != 0) {
       currentName = thrd.getName();
       System.out.println("In " + currentName);
       System.out.println("Name in thrd is " + thrd.getName());
       System.out.println("name in currentName is " + currentName);
       if ("High Priority" == currentName) h++;
       if ("Low Priority" == currentName) l++;
       }
      } while(stop == false && count<10);

     stop = true;
     System.out.println("\n" + thrd.getName() + " terminating.");
     }
    } 

    class PriorityDemo {
     public static void main(String args[]) {
      Priority mt1 = new Priority("High Priority");
      Priority mt2 = new Priority("Low Priority");
      mt1.thrd.setPriority(Thread.NORM_PRIORITY+2);
      mt2.thrd.setPriority(Thread.NORM_PRIORITY-2);

      mt1.thrd.start();
      mt2.thrd.start();

      try {
       mt1.thrd.join();
       mt2.thrd.join();
       } catch(InterruptedException e) {
      System.out.println("Main thread interrupted.");
      }

      System.out.println("\n High priority thread counted to " + mt1.count);
      System.out.println("'n Low priority thread counted to " + mt2.count);
      System.out.println("In 'mt1' \nhigh is " + mt1.h + " and low is " + mt1.l);
      System.out.println("In 'mt2' \nhigh is " + mt2.h + " and low is " + mt2.l);
     }
    }

执行代码的最后两行如下： mt1高是 0 低是（例如）985 mt2高是 0 低是985！

我也试过了 // if（＆＃34; High Priority＆＃34; == thrd.getName（））h ++; if（＆＃34; Low Priority＆＃34; == thrd.getName（））l ++; 但这也没有成功。

Answer 1

这可能会有所帮助。如果我正确地实现你的目标

    package tst;

public class PriorityDemo {
    public static void main(String args[]) {
        Priority mtHigh = new Priority(Priority.HIGH);
        Priority mtLow = new Priority(Priority.LOW);
        mtHigh.thrd.setPriority(Thread.NORM_PRIORITY + 3);
        mtLow.thrd.setPriority(Thread.NORM_PRIORITY - 3);

        mtHigh.thrd.start();
        mtLow.thrd.start();

        try {
            mtHigh.thrd.join();
            mtLow.thrd.join();
        } catch (InterruptedException e) {
            System.out.println("Main thread interrupted.");
        }

        System.out.println("v 2\n High priority thread counted to " + mtHigh.count);
        System.out.println("'n Low priority thread counted to " + mtLow.count);
        System.out.println("In 'mtHigh' \nhigh is " + mtHigh.high + " and low is " + mtHigh.low);
        System.out.println("In 'mtLow' \nhigh is " + mtLow.high + " and low is " + mtLow.low);
    }
}

class Priority implements Runnable {
    public final static String HIGH = "High Priority";
    public final static String LOW = "Low Priority";
    int high = 0;
    int low = 0;
    int count;
    Thread thrd;
    static boolean stop = false;
    String currentName;// why static?

    Priority(String name) {
        thrd = new Thread(this, name);
        count = 0;
        currentName = name;
    }

    public void run() {
        System.out.println(thrd.getName() + " starting.");
        do {
            count++;
            System.out.println("\nThrd " + thrd.getName() + " count " + count);
            if (thrd.getName().contains(currentName)) {
                // currentName = thrd.getName();
                //System.out.println("In " + currentName);
                System.out.println("Name in thrd is " + thrd.getName());
                System.out.println("name in currentName is " + currentName);
                if (currentName.contains(HIGH))
                    high++;
                if (currentName.contains(LOW))
                    low++;
            }
        } while (stop == false && count < 10);

        stop = true;//this static so high runs faster and stops low before its count is 10
        System.out.println("\n" + thrd.getName() + " terminating.");
    }
}

我得到的输出：

低优先级启动。高优先级开始。

Thrd Low Priority count 1

Thrd High Priority count 1 thrd中的名称是thrd中的高优先级名称   是currentName中的低优先级名称是低优先级名称   currentName是高优先级

Thrd High Priority count 2 thrd中的名称是高优先级名称   currentName是高优先级

Thrd High Priority count 3 thrd中的名称是高优先级名称   currentName是高优先级

Thrd Low Priority count 2 thrd中的名称是低优先级名称   currentName是低优先级

Thrd High Priority count 4

Thrd Low Priority count 3 thrd中的名称是低优先级名称   currentName是低优先级名称，thrd是高优先级名称   currentName是高优先级

Thrd Low Priority count 4 thrd中的名称为低优先级

Thrd High Priority count 5 thrd中的名称是高优先级名称   currentName是高优先级

Thrd High Priority count 6 thrd中的名称是高优先级名称   currentName是低优先级

Thrd Low Priority count 5 thrd中的名称是低优先级名称   currentName是低优先级

Thrd Low Priority count 6 thrd中的名称是低优先级名称   currentName是低优先级

Thrd Low Priority count 7 thrd中的名称是低优先级名称   currentName是低优先级

Thrd Low Priority count 8 thrd中的名称是低优先级名称   currentName是低优先级

Thrd Low Priority count 9 thrd中的名称是低优先级名称   currentName是低优先级

Thrd Low Priority count 10 thrd中的名称是低优先级名称   currentName是低优先级

低优先级终止。 currentName中的名称是高优先级

高优先级终止。 v 2高优先级线程计为6＆n; n   低优先级线程计为10 In＆＃39; mtHigh＆＃39;高是6而低是0   在＆＃39; mtLow＆＃39; high为0而low为10

计算线程优先级 - Java

1 个答案: