一.使用jconsole

jconsole是jdk自带的内置java性能分析器,用来监控Java应用程序的性能和跟踪Java中的代码;

它有一个近亲,就是jvisualvm;

那么如何使用呢?

1.很简单,在idea的命令行输入:

D:\java\workspace\AS> jconsole

就可显示出GUI:

这里有一个死锁演示代码:

package com.river.morethread;

public class DealLock implements Runnable{

    public String username;

    public Object lockOne = new Object();

    public Object lockSecond = new Object();

    public void serFlag(String username){
        this.username = username;
    }

    @Override
    public void run() {

        if ("a".equals(username)){
            synchronized (lockOne){
                try {
                    System.out.println("username -> " + username);
                    Thread.sleep(5000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                synchronized (lockSecond){
                    System.out.println("lockOne -> lockSecond");
                }
            }
        }



        if ("b".equals(username)){
            synchronized (lockSecond){
                try {
                    System.out.println("username -> " + username);
                    Thread.sleep(5000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                synchronized (lockOne){
                    System.out.println("lockSecond -> lockOne");
                }
            }
        }

    }


    public static void main(String[] args) throws InterruptedException {
        DealLock d1 = new DealLock();
        d1.serFlag("a");
        new Thread(d1).start();
        Thread.sleep(100);
        d1.serFlag("b");
        new Thread(d1).start();
    }
}

因此Gui选择要查看的进程: