// Utility class to pause thread execution
class Util { 
    static void sleep(long millis)
    {
        try {
            Thread.sleep(millis);
        }
        catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}
// this class is shared by both threads
class Shared {
  
    // first synchronized method
    synchronized void test1(Shared s2)
    {
        System.out.println(Thread.currentThread().getName()
                           + " enters test1 of " + this);
        Util.sleep(1000);
      
        // Trying to call test2 on another object
        s2.test2();
        System.out.println(Thread.currentThread().getName()
                           + " exits test1 of " + this);
    }
  
    // Second synchronized method
//    synchronized
 void test2()
    {
        System.out.println(Thread.currentThread().getName()
                           + " enters test2 of " + this);
        Util.sleep(1000);
      
        // taking object lock of s1 enters into test1 method
        System.out.println(Thread.currentThread().getName()
                           + " exits test2 of " + this);
    }
}

class Thread1 extends Thread {
    private Shared s1;
    private Shared s2;
  
    // constructor to initialize fields
    public Thread1(Shared s1, Shared s2)
    {
        this.s1 = s1;
        this.s2 = s2;
    }
  
    // run method to start a thread
  public void run() { s1.test1(s2); }
}

class Thread2 extends Thread {
    private Shared s1;
    private Shared s2;
  
    // constructor to initialize fields
    public Thread2(Shared s1, Shared s2)
    {
        this.s1 = s1;
        this.s2 = s2;
    }
  
    // run method to start a thread
    public void run() { s2.test1(s1); }
}
public class DealockThreadExam {
  
  // In this class deadlock occurs
    public static void main(String[] args)
    {
        // creating one object
        Shared s1 = new Shared();
        Shared s2 = new Shared();
      
        // creating first thread and starting it
        Thread1 t1 = new Thread1(s1, s2);
        t1.setName("Thread1");
        t1.start();
      
        // creating second thread and starting it
        Thread2 t2 = new Thread2(s1, s2);
        t2.setName("Thread2");
        t2.start();
        Util.sleep(2000);
    }}