多线程小案例

package com.njbdqn;

import jdk.management.resource.internal.inst.InitInstrumentation;

import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ThreadDemo {
static int[] arr = new int[10];
static int i=0;

static void cal1(int ix){
int sum = 0;
for (int i = ix*10+1; i <=(ix+1)*10; i++) {
sum += i;
}
arr[ix] = sum;
i++;
System.out.println(Thread.currentThread().getName()+":"+sum);
}

static int cal3(int ix){
int sum = 0;
for (int i = 0; i < 100; i+=10) {
sum += i+ix+1;
System.out.println(Thread.currentThread().getName()+":"+sum);
}
return sum;
}

static void cal2(int ix){
int sum = 0;
for (int i = 0; i < 100; i+=10) {
sum += i+ix+1;
System.out.println(Thread.currentThread().getName()+":"+sum);
}
arr[ix] = sum;
i++;

}

static class Sum implements Runnable{
private int ix;
public Sum(int ix){
this.ix =ix;
}
@Override
public void run() {
cal2(ix);
}
}

public static void main(String[] args) throws InterruptedException, ExecutionException {
//方法一
// Thread[] ths = new Thread[10];
// for (int i = 0; i < ths.length; i++) {
// ths[i] = new Thread(new Sum(i));
// ths[i].start();
ths[i].join(); //等到这条线程死亡
// }
// while(i<10){
// Thread.sleep(1000);
// }

//方法二
ExecutorService service = Executors.newFixedThreadPool(10);
//顺序执行
// for (int j = 0; j < arr.length; j++) {
// final int _j=j;
// arr[j] = service.submit(new Callable<Integer>() {
// @Override
// public Integer call() throws Exception {
// return cal3(_j);
// }
// }).get();
// }

//并发执行
for (int j = 0; j < arr.length; j++) {
service.submit(new Sum(j));
}

while(i<10){
Thread.sleep(200);
}

int sum = 0;
for (int i = 0; i < arr.length; i++) {
sum += arr[i];
}
System.out.println("sum all : "+sum);

// new Thread(){
// @Override
// public void run() {
// super.run();
// }
// }.start();

}

public class MyThread exends Thread{
   private static Integer count=0;

   public void run(){
       while(true){
           synconized(count) {
               int flag = Integer.parseInt(Thread.currentThread().getName().split("-")[1]);
               if(flag%2==0){
                   count++;
               }else{
                   count--;
               }
           }
       }
   }

   public static void main(String [] args){
       for (int i=0;i<4;i++) {
           new MyThread().start()
       }
   }
}

public class MyThread implements Runable{
   private int count=0;


   public void run() {
       while(true){
           int flag = Integer.parseInt(Thread.currentThread().getName().split("-")[1]);
           if(flag%2==0){
               add();
           }else{
               sub();
           }
       }
   }

   public synconized void add(){ count++;   }
   public synconized void sub(){ count--;   }

   public static void main(String [] args){
       MyThread mt1 = new MyThread();
       for (int i=0;i<4;i++) {
           new Thread(mt1).start();
       }
   }
}

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