代码详解の多线程下的代码死锁

package com.sdmjhca.springBootDemo.deadlock;

import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
* @author JHMI on 2017/8/20 0020.
* 此种生成死锁的方式注意下列问题：
* 1、测试类内部定义的对象不能是静态的
* 2、synchronized必须是嵌套锁
*/
public class DeadLockMain {
public static void main(String args[]) throws InterruptedException {
/*DeadLoakTest t1 = new DeadLoakTest(true);

DeadLoakTest t2 = new DeadLoakTest(false);
t1.start();
t2.start();*/
/*ExecutorService executor = Executors.newCachedThreadPool();
executor.execute(t1);
executor.execute(t2);*/
Object o1 = new String("11111111111111111");
Object o2 = new String("22222222222222");
DeadLoakTest2 test2 = new DeadLoakTest2(o1,o2);
//Thread.sleep(1000);
DeadLoakTest2 test21 = new DeadLoakTest2(o2,o1);
test2.start();
test21.start();

}
}

package com.sdmjhca.springBootDemo.deadlock;

/**
* @author JHMI on 2017/8/20 0020.
*/
public class DeadLoakTest extends Thread {
boolean flag;
public DeadLoakTest(boolean temp){
flag = temp;
}
public void run(){
if(flag){
lock(Resource.o1,Resource.o2);
}else{
lock(Resource.o2,Resource.o1);
}
}
public void lock(Object o1,Object o2){
synchronized (o1){
System.out.println("已经获得对象1的锁，"+o1);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
synchronized (o2){
System.out.println("已经获得对象2的锁,"+o2);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}

}
}
}
}

package com.sdmjhca.springBootDemo.deadlock;

/**
* @author JHMI on 2017/8/20 0020.
* 此种生成死锁的方式注意下列问题：
* 1、测试类内部定义的对象不能是静态的
* 2、synchronized必须是嵌套锁
*/
public class DeadLoakTest2 extends Thread {
boolean flag;
//局部变量是线程私有的
Object o1;
Object o2;
/**
* 此处注意不能使用static修饰符，
*/
//static静态变量和常量是线程公有的
static Object o3;
static Object o4;

public DeadLoakTest2(boolean temp){
flag = temp;
}
public DeadLoakTest2(Object o1,Object o2){
this.o1 = o1;
this.o2 = o2;
}
public void run(){
lock(o1,o2);
}
public void lock(Object o1,Object o2){
synchronized (o1){
System.out.println("已经获得对象1的锁，"+o1);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
synchronized (o2){
System.out.println("已经获得对象2的锁,"+o2);
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}

}
}

}
}

package com.sdmjhca.springBootDemo.deadlock;

/**
* @author JHMI on 2017/8/20 0020.
*/
public class Resource {
static final Object o1 = new String("1111");
static final Object o2 = new String("2222");
}