Semaphore hold the thread

SemaphoreTest.java

package com.zavakid.concurrent;

import java.util.concurrent.Semaphore;

import org.junit.Test;

/**
 * @author Zava 2012-10-12 下午1:06:15
 * @version 1.0
 */
public class SemaphoreTest {

    private final Semaphore sempahore = new Semaphore(5);

    @Test
    public void test() throws InterruptedException {
        Thread thread1 = new Thread(new Runnable() {

            @Override
            public void run() {
                try {
                    System.out.println("thread1 started acquire 4 ");
                    sempahore.acquire(4);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                System.out.println("thread1 has acquired 4, done...");
            }
        });
        thread1.start();
        thread1.join();

        Thread thread2 = new Thread(new Runnable() {

            @Override
            public void run() {
                try {
                    System.out.println("thread2 started acquire 1");
                    sempahore.acquire(1);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                System.out.println("thread2 has acquired 1, done...");
            }
        });
        thread2.start();
        thread2.join();

        Thread thread3 = new Thread(new Runnable() {

            @Override
            public void run() {
                try {
                    System.out.println("thread3 started acquire 2");
                    sempahore.acquire(2);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                System.out.println("thread3 has acquired 2, done...");
            }
        }, "thread-3");
        thread3.start();

        System.out.println("sleep 1s");
        Thread.sleep(1000);
        System.out.println("wake up now");

        Thread thread4 = new Thread(new Runnable() {

            @Override
            public void run() {
                try {
                    System.out.println("thread4 started acquire 1");
                    sempahore.acquire(1);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                System.out.println("thread4 has acquired 1, done...");
            }
        }, "thread-4");
        thread4.start();

        System.out.println("sleep 1s");
        Thread.sleep(1000);
        System.out.println("wake up now");

        Thread thread5 = new Thread(new Runnable() {

            @Override
            public void run() {
                System.out.println("thread5 started release 1");
                sempahore.release(1);
                System.out.println("thread5 has release 1, done...");
            }
        }, "thread-5");
        thread5.start();

        thread3.join();
        thread4.join();
        System.out.println("all done, but never reach here...");

    }
}

this code is needed @ http://www.zavakid.com/207