j在多线程中java关键字synchronized的修饰静态方法和非静态方法得到的不同情况

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在java的同步关键字synchronized  我们知道用在多线程同步并发情况下，用来在修饰方法或者代码块上

修饰方法 监视的是整个对象 那么如果修饰的分别是静态方法和非静态方法呢 ，效果一样吗？

下面请看我这个例子

 

package com.test.thread;

public class SynchronizedClass {
   
   /**
	* 非静态 synchroized 方法
 * @throws InterruptedException 
   */
 public  synchronized void nonStaticFunction1() throws InterruptedException{
	for(int i=0;i<20;i++ ){
		Thread.sleep(300);
		System.out.println("nonstaticFunc1 is  running  times"+i);
	}	 
 }	
 /**
  * 非静态 synchroized 方法
 * @throws InterruptedException 
  */
 public  synchronized void nonStaticFunction2() throws InterruptedException{
		for(int i=0;i<20;i++ ){
			Thread.sleep(300);
			System.out.println("nonstaticFunc2 is  running  times"+i);
		}	 
 }
 /**
  * 静态 synchroized 方法
 * @throws InterruptedException 
  */
 public static synchronized void staticFunction() throws InterruptedException{
		for(int i=0;i<20;i++ ){
			Thread.sleep(300);
			System.out.println("staticFunc2 is  running  times"+i);
		}	 
 
 }
}

  下面是测试代码

 

package com.test.thread;

public class SynchronizedTest {
  
	public static void main(String[] args) throws InterruptedException {
		final SynchronizedClass cls= new SynchronizedClass();
	    Thread t1=new Thread(){
	    	public void run() {
	    		try {
					cls.nonStaticFunction1();
				} catch (InterruptedException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
	    	};
	    };
	    
	    Thread t2=new Thread(){
	    	public void run() {
	    		try {
					cls.nonStaticFunction2();
				} catch (InterruptedException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
	    	};
	    };
	    Thread t3=new Thread(){
	    	public void run() {
	    		try {
					cls.staticFunction();
				} catch (InterruptedException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
	    	};
	    };
	    t1.start();
	    t2.start();
	    t3.start();
	}
	
	
}

  运行结果 如下

nonstaticFunc1 is  running  times0
staticFunc2 is  running  times0
staticFunc2 is  running  times1
nonstaticFunc1 is  running  times1
staticFunc2 is  running  times2
nonstaticFunc1 is  running  times2
staticFunc2 is  running  times3
nonstaticFunc1 is  running  times3
staticFunc2 is  running  times4
nonstaticFunc1 is  running  times4
staticFunc2 is  running  times5
nonstaticFunc1 is  running  times5
staticFunc2 is  running  times6
nonstaticFunc1 is  running  times6
staticFunc2 is  running  times7
nonstaticFunc1 is  running  times7
staticFunc2 is  running  times8
nonstaticFunc1 is  running  times8
staticFunc2 is  running  times9
nonstaticFunc1 is  running  times9
staticFunc2 is  running  times10
nonstaticFunc1 is  running  times10
staticFunc2 is  running  times11
nonstaticFunc1 is  running  times11
staticFunc2 is  running  times12
nonstaticFunc1 is  running  times12
staticFunc2 is  running  times13
nonstaticFunc1 is  running  times13
staticFunc2 is  running  times14
nonstaticFunc1 is  running  times14
staticFunc2 is  running  times15
nonstaticFunc1 is  running  times15
staticFunc2 is  running  times16
nonstaticFunc1 is  running  times16
staticFunc2 is  running  times17
nonstaticFunc1 is  running  times17
staticFunc2 is  running  times18
nonstaticFunc1 is  running  times18
staticFunc2 is  running  times19
nonstaticFunc1 is  running  times19
nonstaticFunc2 is  running  times0
nonstaticFunc2 is  running  times1
nonstaticFunc2 is  running  times2
nonstaticFunc2 is  running  times3
nonstaticFunc2 is  running  times4
nonstaticFunc2 is  running  times5
nonstaticFunc2 is  running  times6
nonstaticFunc2 is  running  times7
nonstaticFunc2 is  running  times8
nonstaticFunc2 is  running  times9
nonstaticFunc2 is  running  times10
nonstaticFunc2 is  running  times11
nonstaticFunc2 is  running  times12
nonstaticFunc2 is  running  times13
nonstaticFunc2 is  running  times14
nonstaticFunc2 is  running  times15
nonstaticFunc2 is  running  times16
nonstaticFunc2 is  running  times17
nonstaticFunc2 is  running  times18
nonstaticFunc2 is  running  times19

  

由上述运行结果可知 静态方法staticFunc2 和 非静态方法nonstaticFunc1 交替执行，而非静态方法 nonstaticFunc1 和nonstaticFunc2两方法则是有先后顺序执行的 说明

静态方法和非静态方法监视的对象不一样，我们知道静态方法属于类对象 那么它监视的对象就是Class类了，而非静态方法属于对象本身 那么他监视的对象就是对象本身了