Deadlock.java Source code

Introduction

Here is the source code for Deadlock.java

Source

public class Deadlock extends Object {
    private String objID;

    public Deadlock(String id) {
        objID = id;
    }

    public synchronized void checkOther(Deadlock other) {
        print("entering checkOther()");

        try {
            Thread.sleep(2000);
        } catch (InterruptedException x) {
        }

        print("invoke 'other.action()'");
        other.action();

        print("leaving checkOther()");
    }

    public synchronized void action() {
        print("entering action()");

        // simulate some work here
        try {
            Thread.sleep(500);
        } catch (InterruptedException x) {
        }

        print("leaving action()");
    }

    public void print(String msg) {
        threadPrint("objID=" + objID + " - " + msg);
    }

    public static void threadPrint(String msg) {
        String threadName = Thread.currentThread().getName();
        System.out.println(threadName + ": " + msg);
    }

    public static void main(String[] args) {
        final Deadlock obj1 = new Deadlock("Thread 1");
        final Deadlock obj2 = new Deadlock("Thread 2");

        Runnable runA = new Runnable() {
            public void run() {
                obj1.checkOther(obj2);
            }
        };

        Thread thread = new Thread(runA, "A");
        thread.start();

        try {
            Thread.sleep(200);
        } catch (InterruptedException x) {
        }

        Runnable runB = new Runnable() {
            public void run() {
                obj2.checkOther(obj1);
            }
        };

        Thread threadB = new Thread(runB, "B");
        threadB.start();

        try {
            Thread.sleep(5000);
        } catch (InterruptedException x) {
        }

        threadPrint("finished sleeping");

        threadPrint("about to interrupt() threadA");
        thread.interrupt();

        try {
            Thread.sleep(1000);
        } catch (InterruptedException x) {
        }

        threadPrint("about to interrupt() threadB");
        threadB.interrupt();

        try {
            Thread.sleep(1000);
        } catch (InterruptedException x) {
        }

        threadPrint("did that break the deadlock?");
    }
}