package 经典;

public class 四个线程 {

    private int j=10;

    /**

     * @param args

     */

    public static void main(String[] args) {

        // TODO Auto-generated method stub

        四个线程 mainClass=new 四个线程();

        for(int i=2; i>0; i--)

        {

            Thread thread=new Thread(mainClass.new IncThread());

            thread.start();

            thread=new Thread(mainClass.new DecThread());

            thread.start();

        }

    }

    private synchronized void inc(){

        j++;

        System.out.println(Thread.currentThread().getName()+", j="+j);

    }

    private synchronized void dec(){

        j--;

        System.out.println(Thread.currentThread().getName()+", j="+j);

    }

    class IncThread implements Runnable{

        @Override

        public void run() {

            // TODO Auto-generated method stub

            for(int i=20; i>0 ;i--)

                inc();

        }

    }

    class DecThread implements Runnable{

        @Override

        public void run() {

            // TODO Auto-generated method stub

            for(int i=20; i>0 ;i--)

                dec();

        }

    }

}