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 */

package quickie;

import java.util.logging.Level;
import java.util.logging.Logger;

/**
 *
 * @author bnevins
 */
public class DeadLock {
    public static void main(String... args) {
        if(args.length > 0)
            deadlock = true;
        
        try {
            new Thread(new T1("A")).start();
            new Thread(new T2("B")).start();
            new Thread(new T2("C")).start();
            new Thread(new T1("D")).start();
            new Thread(new T2("E")).start();
            new Thread(new T1("F")).start();
        }
        catch (Exception ex) {
        }
    }

    private static void sleep(int msec) {
        try {
            Thread.sleep(msec);
        }
        catch (InterruptedException ex) {
            // ignore
        }
    }

    private final static Object L1 = new Object();
    private final static Object L2 = new Object();
    private static boolean deadlock = false;

    private static class T1 implements Runnable {
        T1(String s) {
            name = s;
        }
        public void run() {
            while(true) {
                synchronized(L1) {
                    System.out.println("T1-" + name + " got First");
                    sleep(10);
                    synchronized(L2) {
                    System.out.println("T1-" + name + " got Second");
                        sleep(10);
                    }
                }
                sleep(2000);
            }
        }
        String name;
    }
    private static class T2 implements Runnable {
        T2(String s) {
            name = s;
            if(deadlock) {
                lock1 = L2;
                lock2 = L1;
            }
            else {
                lock1 = L1;
                lock2 = L2;
            }
        }
        public void run() {
            while(true) {
                synchronized(lock1) {
                    System.out.println("T2-" + name + " got First");
                    sleep(10);
                    synchronized(lock2) {
                    System.out.println("T2-" + name + " got Second");
                        sleep(10);
                    }
                }
                sleep(2000);
            }
        }
        String name;
        Object lock1, lock2;
    }

}