TestCases to understand Thread.State

Explainations of Thread.State:
        /**
         * Thread state for a thread which has not yet started.
         */
        NEW,
       
        /**
         * Thread state for a runnable thread.  A thread in the runnable
         * state is executing in the Java virtual machine but it may
         * be waiting for other resources from the operating system
         * such as processor.
         */
        RUNNABLE,
       
        /**
         * Thread state for a thread blocked waiting for a monitor lock.
         * A thread in the blocked state is waiting for a monitor lock
         * to enter a synchronized block/method or
         * reenter a synchronized block/method after calling
         * {@link Object#wait() Object.wait}.
         */
        BLOCKED,
   
        /**
         * Thread state for a waiting thread.
         * A thread is in the waiting state due to calling one of the
         * following methods:
         * <ul>
         *   <li>{@link Object#wait() Object.wait} with no timeout</li>
         *   <li>{@link Thread#join() Thread.join} with no timeout</li>
         *   <li>{@link LockSupport#park() LockSupport.park}</li>
         * </ul>
         *
         * <p>A thread in the waiting state is waiting for another thread to
         * perform a particular action. 
         *
         * For example, a thread that has called <tt>Object.wait()</tt>
         * on an object is waiting for another thread to call
         * <tt>Object.notify()</tt> or <tt>Object.notifyAll()</tt> on
         * that object. A thread that has called <tt>Thread.join()</tt>
         * is waiting for a specified thread to terminate.
         */
        WAITING,
       
        /**
         * Thread state for a waiting thread with a specified waiting time.
         * A thread is in the timed waiting state due to calling one of
         * the following methods with a specified positive waiting time:
         * <ul>
         *   <li>{@link Thread#sleep Thread.sleep}</li>
         *   <li>{@link Object#wait(long) Object.wait} with timeout</li>
         *   <li>{@link Thread#join(long) Thread.join} with timeout</li>
         *   <li>{@link LockSupport#parkNanos LockSupport.parkNanos}</li>
         *   <li>{@link LockSupport#parkUntil LockSupport.parkUntil}</li>
         * </ul>
         */
        TIMED_WAITING,

        /**
         * Thread state for a terminated thread.
         * The thread has completed execution.
         */
        TERMINATED;
    }



TestCases to understand Thread.State:
import junit.framework.TestCase;
import junit.framework.Assert;

public class ThreadStateTest extends TestCase {
    private Thread thread;
   
    public void setUp()throws Exception
    {
        super.setUp();
        thread = new Thread();
    }
    public void testThreadIsInNewStateAfterConstructedBeforeStarted()
    {
        Assert.assertEquals(Thread.State.NEW, thread.getState());

        thread.start();
        Assert.assertTrue("Thread state is not NEW after call of start()",Thread.State.NEW != thread.getState());
    }
   
    public void testThreadIsInRunnableStateAfterStarted()
    {
        thread.start();
        Assert.assertEquals(Thread.State.RUNNABLE, thread.getState());
    }
   
    public void testThreadIsInWaitingState(){
        thread = new Thread()
        {
            private Object lock = new Object();
            public void run()
            {
                synchronized(lock)
                {
                    try{
                        System.out.println("Getting into lock.wait()");
                        lock.wait();
                    }catch(InterruptedException interruptedEx)
                    {
                        interruptedEx.printStackTrace();
                    }
                }
            }
        };
        thread.start();
       
        //here hold a sec,make sure this thread gets the monitor.
        holdASec();
        Assert.assertEquals(Thread.State.WAITING,thread.getState());
    }
   
    public void testThreadIsInTimedWaitingState(){
        thread = new Thread()
        {
            private Object lock = new Object();
            public void run()
            {
                synchronized(lock)
                {
                    try{
                        System.out.println("Getting into lock.wait(time)");
                        lock.wait(50000);
                    }catch(InterruptedException interruptedEx)
                    {
                        interruptedEx.printStackTrace();
                    }
                }
            }
        };
        thread.start();
       
        //here hold a sec,make sure this thread gets the monitor.
        holdASec();
        Assert.assertEquals(Thread.State.TIMED_WAITING,thread.getState());
    }
   
    public void testThreadIsInBlockStateWhenWaitingToGetMonitor()
    {
        final Object sharedLock = new Object();
       
        Thread anotherThreadHoldsTheLockForAWhile = new Thread()
        {
            public void run()
            {
                synchronized(sharedLock)
                {
                    System.out.println(getName() + "holding sharedLock");
                   
                    try{
                        Thread.sleep(50000);
                    }catch(InterruptedException e)
                    {
                        e.printStackTrace();                           
                    }
                }
            }
        };
        anotherThreadHoldsTheLockForAWhile.start();
       
        //holds a sec to ensure the thread anotherThreadHoldsTheLockForAWhile got the sharedLock first
        holdASec();
        thread = new Thread()
        {
            public void run()
            {
                synchronized(sharedLock)
                {
                    System.out.println("Got the lock");
                }
            }
        };
        thread.start();
        holdASec();
        Assert.assertEquals(Thread.State.BLOCKED, thread.getState());
    }
   
    public void testThreadIsInTerminatedStateAfterCompletion()
    {
        thread.start();
        holdASec();
        Assert.assertEquals(Thread.State.TERMINATED, thread.getState());
    }
   
    private void holdASec()
    {
        try{
            Thread.sleep(5000);
        }catch(InterruptedException e)
        {
            e.printStackTrace();
        }   
    }
}


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