操作方法
首先要明确，线程间的通讯问题，就是让多个线程操作同一个资源
其次 通过代码来解决这些问题 首先： 新建一个共享资源 class Res { String name; String sex; }
其次建立两个线程，来操作这个资源 class Input implements Runnable { Res r; Input(Res r) { this.r=r; } public void run() { boolean b =true; while(true) { if(b) { r.name="lishi"; r.sex="man"; b = false; } else { r.name="李四"; r.sex="男"; b = true; } } } } } class Output implements Runnable { Res r; Output(Res r) { this.r=r; } public void run() { while(true) { System.out.println(r.name+" "+r.sex); } } } 然后新建一个测试类： public class Demo { public static void main(String[] args) { Res r = new Res(); Input in = new Input(r); Output out = new Output(r); Thread t = new Thread(in ); Thread tl = new Thread(out); t.start(); tl.start(); } } 我们会发现些小程序在运行过程中会出现安全问题，那么要解决线程间的安全问题，就需要用到同步代码块的知识 我们要以将上面的代码改写：
class Res{ String name; String sex; }class Input implements Runnable{ Res r; Input(Res r) { this.r=r; } public void run() { boolean b =true; while(true) { synchronized(r) { if(b) { r.name="lishi"; r.sex="man"; b = false; } else { r.name="李四"; r.sex="男"; b = true; } } } } }class Output implements Runnable{ Res r; Output(Res r) { this.r=r; } public void run() { while(true) { synchronized(r) { System.out.println(r.name+" "+r.sex); } } } } 这样的话就解决了线程间的安全问题了 输出正确的结果应该为
生产者与 消费者问题
public class StringDemo { public static void main(String[] args) { Resourced r = new Resourced(); new Thread(new Producerd(r)).start();//1 new Thread(new Producerd(r)).start();//2 new Thread(new Consumerd(r)).start();//3 new Thread(new Consumerd(r)).start();//4 } } /* * 生产一个，消费一个*/ class Resourced { private String name; private int count = 1; private boolean flag = false; public synchronized void set(String name) { while(flag) try{wait();}catch(Exception e){} this.name = name+" "+count++; System.out.println(Thread.currentThread().getName()+"生产者,,,," + this.name); flag = true; this.notifyAll(); } public synchronized void out() { while(!flag) try{wait();}catch(Exception e){} System.out.println(Thread.currentThread().getName()+"消费者 " + this.name); flag = false; this.notifyAll(); } } class Producerd implements Runnable { private Resourced res ; Producerd(Resourced res) { this.res = res; } public void run() { while(true) { res.set("商品"); } } } class Consumerd implements Runnable { private Resourced res; Consumerd(Resourced res) { this.res = res; } public void run() { while(true) { res.out(); } } }