2.1.7出现异常的线程自动释放锁

package cha02.execise09;/** * Created by sunyifeng on 17/9/24. */public class Service {    synchronized public void testMethod() {        if (Thread.currentThread().getName().equals("a")) {            System.out.println("thread name:" + Thread.currentThread().getName() + ",当前时间：" + System.currentTimeMillis());            while (true) {                if (("" + Math.random()).substring(0, 8).equals("0.123456")) {                    System.out.println("thread name:" + Thread.currentThread().getName() + ",当前时间：" + System.currentTimeMillis());                    // TODO: 这里出现异常                    Integer.parseInt("a");                }            }        } else {            System.out.println("Thread B run time = " + System.currentTimeMillis());        }    }}

package cha02.execise09;/** * Created by sunyifeng on 17/9/24. */public class ThreadA extends Thread {    private Service service;    public ThreadA(Service service) {        super();        this.service = service;    }    @Override    public void run(){        service.testMethod();    }}

package cha02.execise09;/** * Created by sunyifeng on 17/9/24. */public class ThreadB extends Thread {    private Service service;    public ThreadB(Service service) {        super();        this.service = service;    }    @Override    public void run(){        service.testMethod();    }}

package cha02.execise09;/** * Created by sunyifeng on 17/9/24. */public class Test {    public static void main(String[] args) {        try {            Service service = new Service();            // 线程A            ThreadA threadA = new ThreadA(service);            threadA.setName("a");            threadA.start();            Thread.sleep(0);            // 线程B            ThreadB threadB = new ThreadB(service);            threadB.setName("b");            threadB.start();        } catch (InterruptedException e) {            e.printStackTrace();        }    }}

运行结果：

thread name:a,当前时间：1507651297645
Exception in thread "a" thread name:a,当前时间：1507651298658
java.lang.NumberFormatException: For input string: "a"
Thread B run time = 1507651298658
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:580)
at java.lang.Integer.parseInt(Integer.java:615)
at cha02.execise09.Service.testMethod(Service.java:14)
at cha02.execise09.ThreadA.run(ThreadA.java:16)

程序分析：

1、当某个线程出现异常时，自动释放锁；

2、其他线程获取对象锁后，可继续执行。