标签:继承 extend rgs ssi can main nal rri 线程优先级
多线程优先级为1~10,数字越大,优先级越高。
一个线程不设置优先级的话,默认优先级为5;
/**
* The minimum priority that a thread can have.
*/
public final static int MIN_PRIORITY = 1;
/**
* The default priority that is assigned to a thread.
*/
public final static int NORM_PRIORITY = 5;
/**
* The maximum priority that a thread can have.
*/
public final static int MAX_PRIORITY = 10;
以上,是Thread类提供的三个优先级常量。
设置优先级的方法为,Thread对象或继承了Thread类的对象,调用setPriority( )方法。
package com.xm.thread.t_19_01_26;
import java.util.concurrent.TimeUnit;
public class PriorityThread {
public static void main(String[] args) throws InterruptedException {
HightPriorityThread hightPriorityThread = new HightPriorityThread();
LowPriorityThread lowPriorityThread = new LowPriorityThread();
hightPriorityThread.setPriority(Thread.MAX_PRIORITY);
lowPriorityThread.setPriority(Thread.MIN_PRIORITY);
lowPriorityThread.start();
hightPriorityThread.start();
TimeUnit.SECONDS.sleep(1);
System.out.println("默认优先级别!");
}
}
class HightPriorityThread extends Thread{
@Override
public void run() {
try {
TimeUnit.SECONDS.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("优先级别高!");
}
}
class LowPriorityThread extends Thread{
@Override
public void run() {
try {
TimeUnit.SECONDS.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("优先级别低!");
}
}
第1次运行结果:
优先级别高!
默认优先级别!
优先级别低!
第2次运行结果:
默认优先级别!
优先级别高!
优先级别低!
虽然优先级别可以设置,但通过以上运行结果我们可以看出,它并不能真正控制线程在CPU上的调度顺序。
标签:继承 extend rgs ssi can main nal rri 线程优先级
原文地址:https://www.cnblogs.com/TimerHotel/p/thread03.html