package syn_out_asyn;import java.util.ArrayList;
import java.util.List;/*** Created by Administrator on 2017/1/19 0019.*/
public class MyList {private List list = new ArrayList();synchronized public void add(String username){System.out.println("ThreadName="+Thread.currentThread().getName()+"执行了add方法");list.add(username);System.out.println("ThreadName="+Thread.currentThread().getName()+"退出了add方法");}synchronized public int getSize(){System.out.println("ThreadName= "+Thread.currentThread().getName()+"执行了getSize方法");int sizeValue= list.size();System.out.println("ThreadName= "+Thread.currentThread().getName()+"退出了getSize方法");return  sizeValue;}
}

package syn_out_asyn;/*** Created by Administrator on 2017/1/19 0019.*/
public class ThreadA extends Thread {private MyList list;public ThreadA (MyList list){super();this.list = list;}public void run(){for(int i=0;i<10000;i++){list.add("ThreadA"+(i+1));}}
}

package syn_out_asyn;/*** Created by Administrator on 2017/1/19 0019.*/
public class ThreadB extends Thread {private MyList list;public ThreadB(MyList list){super();this.list = list;}public void run(){for(int i=0;i<10000;i++){list.add("threadB"+(i+1));}}
}

package syn_out_asyn;/*** Created by Administrator on 2017/1/19 0019.*/
public class Run {public static void  main(String[] args){MyList myList = new MyList();ThreadA threadA =  new ThreadA(myList);threadA.setName("A");threadA.start();ThreadB threadB = new ThreadB(myList);threadB.setName("B");threadB.start();}
}

执行结果：
ThreadName=A执行了add方法
ThreadName=A退出了add方法
ThreadName=A执行了add方法
ThreadName=A退出了add方法
ThreadName=A执行了add方法
ThreadName=A退出了add方法
ThreadName=B执行了add方法
ThreadName=B退出了add方法
ThreadName=B执行了add方法
ThreadName=B退出了add方法
ThreadName=B执行了add方法
ThreadName=B退出了add方法

package t9;import java.util.ArrayList;
import java.util.List;/*** Created by Administrator on 2017/1/20 0020.*/
public class MyOneList {private List list  = new ArrayList();synchronized  public void add(String  data){list.add(data);}synchronized public  int getSize(){return list.size();}
}

package t9;/*** Created by Administrator on 2017/1/20 0020.*/
public class MyService {public MyOneList addServiceMethod(MyOneList list ,String data) {try {if (list.getSize() < 1) {Thread.sleep(2000);//模拟从远程话费2秒取回数据
                list.add(data);}} catch (InterruptedException e) {e.printStackTrace();}return list;}
}

package t9;/*** Created by Administrator on 2017/1/20 0020.*/
public class MyThread1 extends Thread {private MyOneList list;public MyThread1(MyOneList list){super();this.list=list;}public void run(){MyService myService = new MyService();myService.addServiceMethod(list,"A");}
}

package t9;/*** Created by Administrator on 2017/1/20 0020.*/
public class MyThread2  extends Thread {private MyOneList list;public MyThread2(MyOneList list){super();this.list=list;}public  void run(){MyService myService = new MyService();myService.addServiceMethod(list,"B");}
}

package t9;/*** Created by Administrator on 2017/1/20 0020.*/
public class Run {public static  void main(String [] args) throws InterruptedException {MyOneList list = new MyOneList();MyThread1 thread1 = new MyThread1(list);thread1.setName("A");thread1.start();MyThread2 thread2 = new MyThread2(list);thread2.setName("B");thread2.start();Thread.sleep(6000);System.out.println("listSize="+list.getSize());}
}

运行结果：
listSize=2

package t9;/*** Created by Administrator on 2017/1/20 0020.*/
public class MyService {public MyOneList addServiceMethod(MyOneList list ,String data) {try {synchronized (list) {if (list.getSize() < 1) {Thread.sleep(2000);//模拟从远程话费2秒取回数据
                    list.add(data);}}} catch (InterruptedException e) {e.printStackTrace();}return list;}
}

运行结果：
listSize=1