public class MulitThreadShareData {

    public static void main(String[] args) {

        final ShareData1 data1 = new ShareData1();

        new Thread(new Runnable() {

            public void run() {

                data1.increment();

            }

        }).start();

        new Thread(new Runnable() {

            public void run() {

                data1.decrement();

            }

        }).start();

        new Thread(new MyRunnable1(data1)).start();

        new Thread(new MyRunnable2(data1)).start();

    }

}

class ShareData1 {

    private int j = 0;

    public void increment(){

        for (int i = 0; i < 10; i++) {

            j++;

            System.out.println(j+" now incre ");

        }

    }

    public void decrement(){

        for (int i = 0; i < 10; i++) {

            j--;

            System.err.println(j+" now decre ");

        }

    }

}

class MyRunnable1 implements Runnable{

    private ShareData1 data;

    public MyRunnable1(ShareData1 data){

        this.data = data;

    }

    public void run() {

        data.decrement();

    }

}

class MyRunnable2 implements Runnable{

    private ShareData1 data;

    public MyRunnable2(ShareData1 data){

        this.data = data;

    }

    public void run() {

        data.increment();

    }

}