Java wait notify

我会带着你远行 2022-08-06 11:10 115阅读 0赞

wait和notify的方法一定出现在 synchronized代码块里或者是出现在被synchronized修饰的方法里。

实例:wait 和notify方法的小demo

Sample.java 文件里的内容:

public class Sample  
\{  
private int number;  
  
public synchronized void increase()  
\{  
if(0 != number)  
\{  
try  
\{  
wait();  
\}  
catch (InterruptedException e)  
\{  
e.printStackTrace();  
\}  
\}  
  
number++;  
  
System.out.println(number);  
  
notify();  
\}  
  
  
  
  
  
  
public synchronized void decrease()  
\{  
if(0 == number)  
\{  
try  
\{  
wait();  
\}  
catch (InterruptedException e)  
\{  
e.printStackTrace();  
\}  
\}  
  
number--;  
  
System.out.println(number);  
  
notify();  
\}  
\}

IncreaseThread .java 文件里的内容

public class IncreaseThread extends Thread  
\{  
private Sample sample ;  
  
public IncreaseThread(Sample sample)  
\{  
this.sample = sample;  
\}  
  
@Override  
public void run()  
\{  
for(int i = 0 ; i < 20 ; i++)  
\{  
try  
\{  
Thread.sleep((long) (Math.random() \* 1000));  
\}  
catch (InterruptedException e)  
\{  
e.printStackTrace();  
\}  
  
sample.increase();  
  
\}  
\}  
\}

DecreaseThread.java 文件里的内容

public class DecreaseThread extends Thread  
\{  
private Sample sample;  
  
  
public DecreaseThread(Sample sample)  
\{  
this.sample = sample;  
\}  
  
  
@Override  
public void run()  
\{  
for (int i = 0; i < 20; i++)  
\{  
try  
\{  
Thread.sleep((long) (Math.random() \* 1000));  
\}  
catch (InterruptedException e)  
\{  
e.printStackTrace();  
\}  
  
  
sample.decrease();  
  
  
\}  
\}  
\}

MainTest.java文件里的内容

public class MainTest  
\{  
public static void main(String\[\] args)  
\{  
Sample sample = new Sample();  
  
Thread t1 = new IncreaseThread(sample);  
Thread t2  = new DecreaseThread(sample);  
  
  
  
  
t1.start();  
t2.start();  
  
  
\}  
\}