/**
* 书本:《Thinking In Java》
* 功能:执行线程的时候我们可以设定相应的优先级
* 文件:SimplePriorities.java
* 时间:2015年5月7日15:17:09
* 作者:cutter_point
*/
package Lesson21Concurency;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class SimplePriorities implements Runnable
{
private int countDown = 5;
//这里我们使用volatile时为了确保不进行任何编译器优化
private volatile double d; //volatile它是被设计用来修饰被不同线程访问和修改的变量,如果没有volatile，基本上会导致这样的结果：要么无法编写多线程程序，要么编译器失去大量优化的机会。
private int priority; //设定优先级
public SimplePriorities(int priority)
{
this.priority = priority;
}
@Override
public String toString()
{
return Thread.currentThread() + " : " + countDown;
}
@Override
public void run()
{
Thread.currentThread().setPriority(priority);//设置线程的优先级
//中间进行相应的一些计算
while(true)
{
for(int i = 0; i < 100000; ++i)
{
d += (Math.PI + Math.E) / (double)i;
if(i % 1000 == 0)
Thread.yield(); //这个是表示线程可以更换了
}
System.out.println(this); //输出当前任务的toString
if(--countDown == 0) //当计数减少到0的时候退出任务
return;
}
}
public static void main(String[] args)
{
ExecutorService exec = Executors.newCachedThreadPool(); //建立新的连接池
for(int i = 0; i < 66; ++i) //这里值要很据电脑的来设定，如果电脑性能比较好的话，可能就体现不出来优先级了，我的电脑大概在65到66左右才会完全体现5次的优先级
exec.execute(new SimplePriorities(1)); //这里设定优先级不同的系统优先级个数不同，所以我们只用最大，最小，和中间的
exec.execute(new SimplePriorities(10)); //这里设定优先级不同的系统优先级个数不同，所以我们只用最大，最小，和中间的
exec.shutdown();
}
}
Thread[pool-1-thread-67,10,main] : 5
Thread[pool-1-thread-67,10,main] : 4
Thread[pool-1-thread-67,10,main] : 3
Thread[pool-1-thread-67,10,main] : 2
Thread[pool-1-thread-67,10,main] : 1
Thread[pool-1-thread-2,1,main] : 5
Thread[pool-1-thread-4,1,main] : 5
Thread[pool-1-thread-7,1,main] : 5
Thread[pool-1-thread-10,1,main] : 5
Thread[pool-1-thread-27,1,main] : 5
Thread[pool-1-thread-11,1,main] : 5
Thread[pool-1-thread-18,1,main] : 5
Thread[pool-1-thread-15,1,main] : 5
Thread[pool-1-thread-14,1,main] : 5
Thread[pool-1-thread-19,1,main] : 5
Thread[pool-1-thread-22,1,main] : 5
Thread[pool-1-thread-23,1,main] : 5
Thread[pool-1-thread-31,1,main] : 5
Thread[pool-1-thread-30,1,main] : 5
Thread[pool-1-thread-26,1,main] : 5
Thread[pool-1-thread-3,1,main] : 5
Thread[pool-1-thread-34,1,main] : 5
Thread[pool-1-thread-38,1,main] : 5
Thread[pool-1-thread-35,1,main] : 5
Thread[pool-1-thread-1,1,main] : 5
Thread[pool-1-thread-39,1,main] : 5
Thread[pool-1-thread-42,1,main] : 5
Thread[pool-1-thread-46,1,main] : 5
Thread[pool-1-thread-43,1,main] : 5
Thread[pool-1-thread-50,1,main] : 5
Thread[pool-1-thread-5,1,main] : 5
Thread[pool-1-thread-51,1,main] : 5
Thread[pool-1-thread-6,1,main] : 5
Thread[pool-1-thread-9,1,main] : 5
Thread[pool-1-thread-55,1,main] : 5
Thread[pool-1-thread-47,1,main] : 5
Thread[pool-1-thread-54,1,main] : 5
Thread[pool-1-thread-58,1,main] : 5
Thread[pool-1-thread-59,1,main] : 5
Thread[pool-1-thread-66,1,main] : 5
Thread[pool-1-thread-62,1,main] : 5
Thread[pool-1-thread-8,1,main] : 5
Thread[pool-1-thread-12,1,main] : 5
Thread[pool-1-thread-13,1,main] : 5
Thread[pool-1-thread-63,1,main] : 5
Thread[pool-1-thread-17,1,main] : 5
Thread[pool-1-thread-21,1,main] : 5
Thread[pool-1-thread-24,1,main] : 5
Thread[pool-1-thread-28,1,main] : 5
Thread[pool-1-thread-20,1,main] : 5
Thread[pool-1-thread-29,1,main] : 5
Thread[pool-1-thread-16,1,main] : 5
Thread[pool-1-thread-25,1,main] : 5
Thread[pool-1-thread-33,1,main] : 5
Thread[pool-1-thread-41,1,main] : 5
Thread[pool-1-thread-57,1,main] : 5
Thread[pool-1-thread-32,1,main] : 5
Thread[pool-1-thread-44,1,main] : 5
Thread[pool-1-thread-40,1,main] : 5
Thread[pool-1-thread-60,1,main] : 5
Thread[pool-1-thread-56,1,main] : 5
Thread[pool-1-thread-53,1,main] : 5
Thread[pool-1-thread-45,1,main] : 5
Thread[pool-1-thread-52,1,main] : 5
Thread[pool-1-thread-64,1,main] : 5
Thread[pool-1-thread-49,1,main] : 5
Thread[pool-1-thread-48,1,main] : 5
Thread[pool-1-thread-36,1,main] : 5
Thread[pool-1-thread-37,1,main] : 5
Thread[pool-1-thread-61,1,main] : 5
Thread[pool-1-thread-65,1,main] : 5
Thread[pool-1-thread-2,1,main] : 4
Thread[pool-1-thread-7,1,main] : 4
Thread[pool-1-thread-27,1,main] : 4
Thread[pool-1-thread-10,1,main] : 4
Thread[pool-1-thread-11,1,main] : 4
Thread[pool-1-thread-14,1,main] : 4
Thread[pool-1-thread-18,1,main] : 4
Thread[pool-1-thread-15,1,main] : 4
Thread[pool-1-thread-23,1,main] : 4
Thread[pool-1-thread-26,1,main] : 4
Thread[pool-1-thread-31,1,main] : 4
Thread[pool-1-thread-34,1,main] : 4
Thread[pool-1-thread-30,1,main] : 4
Thread[pool-1-thread-46,1,main] : 4
Thread[pool-1-thread-39,1,main] : 4
Thread[pool-1-thread-35,1,main] : 4
Thread[pool-1-thread-42,1,main] : 4
Thread[pool-1-thread-19,1,main] : 4
Thread[pool-1-thread-43,1,main] : 4
Thread[pool-1-thread-58,1,main] : 4
Thread[pool-1-thread-6,1,main] : 4
Thread[pool-1-thread-51,1,main] : 4
Thread[pool-1-thread-22,1,main] : 4
Thread[pool-1-thread-62,1,main] : 4
Thread[pool-1-thread-59,1,main] : 4
Thread[pool-1-thread-55,1,main] : 4
Thread[pool-1-thread-54,1,main] : 4
Thread[pool-1-thread-66,1,main] : 4
Thread[pool-1-thread-38,1,main] : 4
Thread[pool-1-thread-50,1,main] : 4
Thread[pool-1-thread-63,1,main] : 4
Thread[pool-1-thread-3,1,main] : 4
Thread[pool-1-thread-47,1,main] : 4
Thread[pool-1-thread-4,1,main] : 4
Thread[pool-1-thread-1,1,main] : 4
Thread[pool-1-thread-5,1,main] : 4
Thread[pool-1-thread-9,1,main] : 4
Thread[pool-1-thread-13,1,main] : 4
Thread[pool-1-thread-12,1,main] : 4
Thread[pool-1-thread-8,1,main] : 4
Thread[pool-1-thread-17,1,main] : 4
Thread[pool-1-thread-28,1,main] : 4
Thread[pool-1-thread-29,1,main] : 4
Thread[pool-1-thread-24,1,main] : 4
Thread[pool-1-thread-25,1,main] : 4
Thread[pool-1-thread-20,1,main] : 4
Thread[pool-1-thread-33,1,main] : 4
Thread[pool-1-thread-16,1,main] : 4
Thread[pool-1-thread-57,1,main] : 4
Thread[pool-1-thread-41,1,main] : 4
Thread[pool-1-thread-32,1,main] : 4
Thread[pool-1-thread-60,1,main] : 4
Thread[pool-1-thread-40,1,main] : 4
Thread[pool-1-thread-45,1,main] : 4
Thread[pool-1-thread-44,1,main] : 4
Thread[pool-1-thread-36,1,main] : 4
Thread[pool-1-thread-48,1,main] : 4
Thread[pool-1-thread-53,1,main] : 4
Thread[pool-1-thread-64,1,main] : 4
Thread[pool-1-thread-49,1,main] : 4
Thread[pool-1-thread-61,1,main] : 4
Thread[pool-1-thread-56,1,main] : 4
Thread[pool-1-thread-65,1,main] : 4
Thread[pool-1-thread-52,1,main] : 4
Thread[pool-1-thread-37,1,main] : 4
Thread[pool-1-thread-21,1,main] : 4
Thread[pool-1-thread-2,1,main] : 3
Thread[pool-1-thread-7,1,main] : 3
Thread[pool-1-thread-27,1,main] : 3
Thread[pool-1-thread-10,1,main] : 3
Thread[pool-1-thread-11,1,main] : 3
Thread[pool-1-thread-14,1,main] : 3
Thread[pool-1-thread-18,1,main] : 3
Thread[pool-1-thread-15,1,main] : 3
Thread[pool-1-thread-23,1,main] : 3
Thread[pool-1-thread-26,1,main] : 3
Thread[pool-1-thread-31,1,main] : 3
Thread[pool-1-thread-34,1,main] : 3
Thread[pool-1-thread-30,1,main] : 3
Thread[pool-1-thread-39,1,main] : 3
Thread[pool-1-thread-42,1,main] : 3
Thread[pool-1-thread-35,1,main] : 3
Thread[pool-1-thread-19,1,main] : 3
Thread[pool-1-thread-46,1,main] : 3
Thread[pool-1-thread-43,1,main] : 3
Thread[pool-1-thread-51,1,main] : 3
Thread[pool-1-thread-58,1,main] : 3
Thread[pool-1-thread-55,1,main] : 3
Thread[pool-1-thread-6,1,main] : 3
Thread[pool-1-thread-22,1,main] : 3
Thread[pool-1-thread-62,1,main] : 3
Thread[pool-1-thread-66,1,main] : 3
Thread[pool-1-thread-59,1,main] : 3
Thread[pool-1-thread-54,1,main] : 3
Thread[pool-1-thread-38,1,main] : 3
Thread[pool-1-thread-50,1,main] : 3
Thread[pool-1-thread-63,1,main] : 3
Thread[pool-1-thread-3,1,main] : 3
Thread[pool-1-thread-47,1,main] : 3
Thread[pool-1-thread-4,1,main] : 3
Thread[pool-1-thread-1,1,main] : 3
Thread[pool-1-thread-5,1,main] : 3
Thread[pool-1-thread-13,1,main] : 3
Thread[pool-1-thread-9,1,main] : 3
Thread[pool-1-thread-17,1,main] : 3
Thread[pool-1-thread-12,1,main] : 3
Thread[pool-1-thread-8,1,main] : 3
Thread[pool-1-thread-28,1,main] : 3
Thread[pool-1-thread-57,1,main] : 3
Thread[pool-1-thread-29,1,main] : 3
Thread[pool-1-thread-24,1,main] : 3
Thread[pool-1-thread-25,1,main] : 3
Thread[pool-1-thread-20,1,main] : 3
Thread[pool-1-thread-33,1,main] : 3
Thread[pool-1-thread-41,1,main] : 3
Thread[pool-1-thread-16,1,main] : 3
Thread[pool-1-thread-32,1,main] : 3
Thread[pool-1-thread-45,1,main] : 3
Thread[pool-1-thread-40,1,main] : 3
Thread[pool-1-thread-60,1,main] : 3
Thread[pool-1-thread-44,1,main] : 3
Thread[pool-1-thread-53,1,main] : 3
Thread[pool-1-thread-36,1,main] : 3
Thread[pool-1-thread-48,1,main] : 3
Thread[pool-1-thread-64,1,main] : 3
Thread[pool-1-thread-49,1,main] : 3
Thread[pool-1-thread-56,1,main] : 3
Thread[pool-1-thread-61,1,main] : 3
Thread[pool-1-thread-52,1,main] : 3
Thread[pool-1-thread-65,1,main] : 3
Thread[pool-1-thread-37,1,main] : 3
Thread[pool-1-thread-21,1,main] : 3
Thread[pool-1-thread-2,1,main] : 2
Thread[pool-1-thread-7,1,main] : 2
Thread[pool-1-thread-27,1,main] : 2
Thread[pool-1-thread-10,1,main] : 2
Thread[pool-1-thread-14,1,main] : 2
Thread[pool-1-thread-11,1,main] : 2
Thread[pool-1-thread-18,1,main] : 2
Thread[pool-1-thread-23,1,main] : 2
Thread[pool-1-thread-15,1,main] : 2
Thread[pool-1-thread-26,1,main] : 2
Thread[pool-1-thread-31,1,main] : 2
Thread[pool-1-thread-34,1,main] : 2
Thread[pool-1-thread-30,1,main] : 2
Thread[pool-1-thread-42,1,main] : 2
Thread[pool-1-thread-43,1,main] : 2
Thread[pool-1-thread-39,1,main] : 2
Thread[pool-1-thread-35,1,main] : 2
Thread[pool-1-thread-19,1,main] : 2
Thread[pool-1-thread-46,1,main] : 2
Thread[pool-1-thread-58,1,main] : 2
Thread[pool-1-thread-51,1,main] : 2
Thread[pool-1-thread-55,1,main] : 2
Thread[pool-1-thread-6,1,main] : 2
Thread[pool-1-thread-62,1,main] : 2
Thread[pool-1-thread-22,1,main] : 2
Thread[pool-1-thread-66,1,main] : 2
Thread[pool-1-thread-59,1,main] : 2
Thread[pool-1-thread-54,1,main] : 2
Thread[pool-1-thread-38,1,main] : 2
Thread[pool-1-thread-50,1,main] : 2
Thread[pool-1-thread-63,1,main] : 2
Thread[pool-1-thread-3,1,main] : 2
Thread[pool-1-thread-47,1,main] : 2
Thread[pool-1-thread-4,1,main] : 2
Thread[pool-1-thread-1,1,main] : 2
Thread[pool-1-thread-5,1,main] : 2
Thread[pool-1-thread-13,1,main] : 2
Thread[pool-1-thread-17,1,main] : 2
Thread[pool-1-thread-12,1,main] : 2
Thread[pool-1-thread-9,1,main] : 2
Thread[pool-1-thread-8,1,main] : 2
Thread[pool-1-thread-57,1,main] : 2
Thread[pool-1-thread-28,1,main] : 2
Thread[pool-1-thread-20,1,main] : 2
Thread[pool-1-thread-25,1,main] : 2
Thread[pool-1-thread-24,1,main] : 2
Thread[pool-1-thread-29,1,main] : 2
Thread[pool-1-thread-33,1,main] : 2
Thread[pool-1-thread-41,1,main] : 2
Thread[pool-1-thread-16,1,main] : 2
Thread[pool-1-thread-32,1,main] : 2
Thread[pool-1-thread-45,1,main] : 2
Thread[pool-1-thread-40,1,main] : 2
Thread[pool-1-thread-60,1,main] : 2
Thread[pool-1-thread-64,1,main] : 2
Thread[pool-1-thread-36,1,main] : 2
Thread[pool-1-thread-61,1,main] : 2
Thread[pool-1-thread-53,1,main] : 2
Thread[pool-1-thread-49,1,main] : 2
Thread[pool-1-thread-56,1,main] : 2
Thread[pool-1-thread-44,1,main] : 2
Thread[pool-1-thread-37,1,main] : 2
Thread[pool-1-thread-52,1,main] : 2
Thread[pool-1-thread-48,1,main] : 2
Thread[pool-1-thread-65,1,main] : 2
Thread[pool-1-thread-21,1,main] : 2
Thread[pool-1-thread-2,1,main] : 1
Thread[pool-1-thread-7,1,main] : 1
Thread[pool-1-thread-27,1,main] : 1
Thread[pool-1-thread-10,1,main] : 1
Thread[pool-1-thread-14,1,main] : 1
Thread[pool-1-thread-11,1,main] : 1
Thread[pool-1-thread-18,1,main] : 1
Thread[pool-1-thread-15,1,main] : 1
Thread[pool-1-thread-23,1,main] : 1
Thread[pool-1-thread-26,1,main] : 1
Thread[pool-1-thread-31,1,main] : 1
Thread[pool-1-thread-34,1,main] : 1
Thread[pool-1-thread-30,1,main] : 1
Thread[pool-1-thread-43,1,main] : 1
Thread[pool-1-thread-42,1,main] : 1
Thread[pool-1-thread-39,1,main] : 1
Thread[pool-1-thread-35,1,main] : 1
Thread[pool-1-thread-19,1,main] : 1
Thread[pool-1-thread-46,1,main] : 1
Thread[pool-1-thread-51,1,main] : 1
Thread[pool-1-thread-55,1,main] : 1
Thread[pool-1-thread-58,1,main] : 1
Thread[pool-1-thread-6,1,main] : 1
Thread[pool-1-thread-62,1,main] : 1
Thread[pool-1-thread-22,1,main] : 1
Thread[pool-1-thread-66,1,main] : 1
Thread[pool-1-thread-59,1,main] : 1
Thread[pool-1-thread-50,1,main] : 1
Thread[pool-1-thread-54,1,main] : 1
Thread[pool-1-thread-38,1,main] : 1
Thread[pool-1-thread-63,1,main] : 1
Thread[pool-1-thread-3,1,main] : 1
Thread[pool-1-thread-28,1,main] : 1
Thread[pool-1-thread-48,1,main] : 1
Thread[pool-1-thread-20,1,main] : 1
Thread[pool-1-thread-44,1,main] : 1
Thread[pool-1-thread-60,1,main] : 1
Thread[pool-1-thread-16,1,main] : 1
Thread[pool-1-thread-65,1,main] : 1
Thread[pool-1-thread-36,1,main] : 1
Thread[pool-1-thread-9,1,main] : 1
Thread[pool-1-thread-12,1,main] : 1
Thread[pool-1-thread-61,1,main] : 1
Thread[pool-1-thread-21,1,main] : 1
Thread[pool-1-thread-1,1,main] : 1
Thread[pool-1-thread-33,1,main] : 1
Thread[pool-1-thread-25,1,main] : 1
Thread[pool-1-thread-24,1,main] : 1
Thread[pool-1-thread-53,1,main] : 1
Thread[pool-1-thread-52,1,main] : 1
Thread[pool-1-thread-37,1,main] : 1
Thread[pool-1-thread-40,1,main] : 1
Thread[pool-1-thread-4,1,main] : 1
Thread[pool-1-thread-47,1,main] : 1
Thread[pool-1-thread-41,1,main] : 1
Thread[pool-1-thread-49,1,main] : 1
Thread[pool-1-thread-13,1,main] : 1
Thread[pool-1-thread-56,1,main] : 1
Thread[pool-1-thread-29,1,main] : 1
Thread[pool-1-thread-17,1,main] : 1
Thread[pool-1-thread-5,1,main] : 1
Thread[pool-1-thread-8,1,main] : 1
Thread[pool-1-thread-32,1,main] : 1
Thread[pool-1-thread-64,1,main] : 1
Thread[pool-1-thread-45,1,main] : 1
Thread[pool-1-thread-57,1,main] : 1
【ThinkingInJava】59、执行线程的时候我们可以设定相应的优先级
原文地址：http://blog.csdn.net/cutter_point/article/details/45932089
