memory barrier demo

gistfile1.java

/**
 * Project File of Scala, Right Reserved by Darren Studio Works
 * <p/>
 * User: fujohnwang
 * Date: 10/26/11
 */
public class SharedObject {
    public int age;
    public String name;
    public boolean married;

    public volatile long updateBarrier = 0;

    @Override
    public String toString() {
        return new StringBuilder("sharedobject(age=").append(age).append(", name=").append(name).append(", married=").append(married).append(")").toString();
    }
}

/**
 * Project File of Scala, Right Reserved by Darren Studio Works
 * <p/>
 * User: fujohnwang
 * Date: 10/26/11
 */
public class MBRunner {
    public static void main(String[] args) throws Exception {


        final long mb1Value = 1;
        final long mb2Value = 2;
        final long mb3Value = 3;

        final SharedObject so = new SharedObject();

        Thread thread1 = new Thread("writer1") {
            @Override
            public void run() {
                so.age = 32;
                so.updateBarrier = mb1Value;
            }
        };
        Thread thread2 = new Thread("writer2") {
            @Override
            public void run() {
                so.name = "darren";
                so.updateBarrier = mb2Value;
            }
        };
        Thread thread3 = new Thread("writer3") {
            @Override
            public void run() {
                so.married = true;
                so.updateBarrier = mb3Value;
            }
        };
        Thread reader1 = new Thread("reader1") {
            @Override
            public void run() {
                System.out.println("after thread1:" + so.toString());
            }
        };

        Thread reader2 = new Thread("reader2") {
            @Override
            public void run() {
                System.out.println("after thread2:" + so.toString());
            }
        };
        Thread reader3 = new Thread("reader3") {
            @Override
            public void run() {
                System.out.println("after thread3:" + so.toString());
            }
        };


        //
        thread1.start();
        thread1.join();
        reader1.start();
        reader1.join();
        //
        thread2.start();
        thread2.join();
        reader2.start();
        reader2.join();
        //
        thread3.start();
        thread3.join();
        reader3.start();
        reader3.join();
    }
}