Deadlock Demo in java

class A
{
B b;

synchronized void a1()
{
System.out.println("Starting a1");
b.b2();
}

synchronized void a2()
{
System.out.println("Starting a2");
}
}

class B
{
A a;

synchronized void b1() {
System.out.println("Starting b1");
a.a2();
}

synchronized void b2() {
System.out.println("Starting b2");
}
}

class Thread1 extends Thread {
A a;

Thread1(A a) {
this.a = a;
}

public void run() {
for(int i = 0; i <>
a.a1();
}
}

class Thread2 extends Thread {
B b;

Thread2(B b) {
this.b = b;
}

public void run() {
for(int i = 0; i <>
b.b1();
}
}

class DeadlockDemo {

public static void main(String args[]) {

// Create objects
A a = new A();
B b = new B();
a.b = b;
b.a = a;

// Create threads
Thread1 t1 = new Thread1(a);
Thread2 t2 = new Thread2(b);
t1.start();
t2.start();

// Wait for threads to complete
try {
t1.join();
t2.join();
}
catch(Exception e) {
e.printStackTrace();
}

// Display message
System.out.println("Done!");
}
}