package com.demo.bootdemo;
import java.util.HashMap;
import java.util.Map;
import org.springframework.context.ApplicationListener;
import org.springframework.context.event.ContextRefreshedEvent;
import org.springframework.stereotype.Component;
@Component
public class MyListeners implements ApplicationListener<ContextRefreshedEvent> {
 private Map map = new HashMap<>();
 private String lock = "aa";
 @Override
 public void onApplicationEvent(ContextRefreshedEvent arg0) {
  Thread t = new Thread(new Runnable() {
   @Override
   public void run() {
    synchronized (map) {
     System.out.println(Thread.currentThread().getName() + ": 獲得map鎖");
     try {
      Thread.sleep(1000);
     } catch (InterruptedException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
     }
     synchronized (lock) {
      System.out.println(Thread.currentThread().getName() + ": 獲得lock鎖"); 
     }
    }
   }
  }, "t-1");
  Thread t2 = new Thread(new Runnable() {
   @Override
   public void run() {
    synchronized (lock) {
     System.out.println(Thread.currentThread().getName() + ": 獲得lock鎖");
     try {
      Thread.sleep(1000);
     } catch (InterruptedException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
     }
     synchronized (map) {
      System.out.println(Thread.currentThread().getName() + ": 獲得map鎖"); 
     }
    }
   }
  }, "t-2");
  
  t.start();
  t2.start();
 }
}

jdb -connect sun.jvm.hotspot.jdi.SAPIDAttachingConnector:pid=27709

TomChens-MacBook-Pro:Commands tomchen$ ls
appletviewer javadoc  jmap  keytool  serialver
apt  javah  jmc  native2ascii servertool
extcheck javap  jps  orbd  tnameserv
idlj  javaws  jrunscript pack200  unpack200
jar  jcmd  jsadebugd policytool wsgen
jarsigner jconsole jstack  rmic  wsimport
java  jdb  jstat  rmid  xjc
java_home jhat  jstatd  rmiregistry
javac  jinfo  jvisualvm schemagen

jps -l
582 HttpFind
431 RefreshBlog.jar
585 sun.tools.jps.Jps

 jstat -gcutil 431
 S0  S1  E  O  P  YGC  YGCT FGC FGCT  GCT 
 0.00 57.17 12.43 24.74 42.31  13 0.044  0 0.000 0.044

jstat -class 434
Loaded Bytes Unloaded Bytes  Time 
 17095 36897.7  1899 2970.9  14.87

jstack 582
......
......
Found one Java-level deadlock:
=============================
"Thread-199":
 waiting to lock monitor 0x00007facb3027608 (object 0x00000007e786b528, a java.lang.Integer),
 which is held by "Thread-3"
"Thread-3":
 waiting to lock monitor 0x00007facb3026108 (object 0x00000007e786b518, a java.lang.Integer),
 which is held by "Thread-8"
"Thread-8":
 waiting to lock monitor 0x00007facb3027608 (object 0x00000007e786b528, a java.lang.Integer),
 which is held by "Thread-3"

Java stack information for the threads listed above:
===================================================
"Thread-199":
 at HttpFind$SyncAdd.run(HttpFind.java:52)
 - waiting to lock <0x00000007e786b528> (a java.lang.Integer)
 at java.lang.Thread.run(Thread.java:722)
"Thread-3":
 at HttpFind$SyncAdd.run(HttpFind.java:53)
 - waiting to lock <0x00000007e786b518> (a java.lang.Integer)
 - locked <0x00000007e786b528> (a java.lang.Integer)
 at java.lang.Thread.run(Thread.java:722)
"Thread-8":
 at HttpFind$SyncAdd.run(HttpFind.java:53)
 - waiting to lock <0x00000007e786b528> (a java.lang.Integer)
 - locked <0x00000007e786b518> (a java.lang.Integer)
 at java.lang.Thread.run(Thread.java:722)

Found 1 deadlock.