线程池 问题求教~

package a.b.threadpool;



import java.util.concurrent.ArrayBlockingQueue;

import java.util.concurrent.BlockingQueue;

import java.util.concurrent.Callable;

import java.util.concurrent.ThreadPoolExecutor;

import java.util.concurrent.TimeUnit;



public class TpTest {

	public static void  main(String[] args){

		 BlockingQueue<Runnable> bqueue = new ArrayBlockingQueue<Runnable>(20); 

         

         ThreadPoolExecutor pool = new ThreadPoolExecutor(3,5,20,TimeUnit.MILLISECONDS,bqueue); 

         pool.execute(new XianChen("线程1"));

         pool.execute(new XianChen("线程2"));

         pool.execute(new XianChen("线程3"));

         pool.execute(new XianChen("线程4"));

         pool.execute(new XianChen("线程5"));

         pool.execute(new XianChen("线程6"));

         pool.execute(new XianChen("线程7"));

         pool.execute(new XianChen("线程8"));

         pool.execute(new XianChen("线程9"));

         pool.execute(new XianChen("线程10"));

         pool.execute(new XianChen("线程11"));

         pool.shutdown();

	}

}



class XianChen extends Thread{

	String name;

	XianChen(String name){

		this.name = name;

	}

	

	public void run() {

		System.out.println(Thread.currentThread().getName()+"进入");

		try {

			Thread.sleep(1500);

		} catch (InterruptedException e) {

			// TODO Auto-generated catch block

			e.printStackTrace();

		}

		//System.out.println(Thread.currentThread().getName()+"退出");

	}

}

new ThreadPoolExecutor(3,5,20,TimeUnit.MILLISECONDS,bqueue) 这个第二个参数的5 是不是最大的运行数？  我现在有11个线程需要运行， 那应该开放5个线程来处理吧 为何看结果他只开放3个呢？ 还是我理解有问题？
------解决方案--------------------
刚看了下，执行时这样

public ThreadPoolExecutor(int corePoolSize,

                          int maximumPoolSize,

                          long keepAliveTime,

                          TimeUnit unit,

                          BlockingQueue<Runnable> workQueue)

在这构造方法中，优先级处理任务的优先级为： 
核心线程corePoolSize、任务队列workQueue、最大线程maximumPoolSize。意思是只有当corePoolSize中任务满了，会先放到workQueue缓冲队列中，缓冲队列满了，才会放到maximumPoolSize里面去。