2.1.7出现异常,锁自动释放
当一个线程执行代码的时候出现异常,则其所持有的锁会自动释放。
package com.cky.bean; /** * Created by chenkaiyang on 2017/12/5. */ public class Service { synchronized public void testMethod() { if (Thread.currentThread().getName().equals("A")) { System.out.println(Thread.currentThread().getName() +" & aaaaaaa"); Integer.parseInt("a"); System.out.println("end"); } else { System.out.println(Thread.currentThread().getName() +" & bbbbb"); } } }
package com.cky.thread; import com.cky.bean.Service; /** * Created by chenkaiyang on 2017/12/5. */ public class ThreadA extends Thread{ private Service service; public ThreadA(Service service) { super(); this.service = service; } @Override public void run() { super.run(); service.testMethod(); } }
package com.cky.thread; import com.cky.bean.Service; /** * Created by chenkaiyang on 2017/12/5. */ public class ThreadB extends Thread{ private Service service; public ThreadB(Service service) { super(); this.service = service; } @Override public void run() { super.run(); service.testMethod(); } }
package com.cky.test; import com.cky.bean.Service; import com.cky.thread.ThreadA; import com.cky.thread.ThreadB; /** * Created by chenkaiyang on 2017/12/2. */ public class Test { public static void main(String[] args){ try { Service service = new Service(); ThreadA threadA = new ThreadA(service); threadA.setName("A"); threadA.start(); Thread.sleep(500); ThreadB threadB = new ThreadB(service); threadB.setName("B"); threadB.start(); } catch (InterruptedException e) { e.printStackTrace(); } } }
D:\it\jdk1.8\bin\java -Didea.launcher.port=7539 "-Didea.launcher.bin.path=D:\it\idea\IntelliJ IDEA 2016.3.3\bin" -Dfile.encoding=UTF-8 -classpath "D:\it\jdk1.8\jre\lib\charsets.jar;D:\it\jdk1.8\jre\lib\deploy.jar;D:\it\jdk1.8\jre\lib\ext\access-bridge-64.jar;D:\it\jdk1.8\jre\lib\ext\cldrdata.jar;D:\it\jdk1.8\jre\lib\ext\dnsns.jar;D:\it\jdk1.8\jre\lib\ext\jaccess.jar;D:\it\jdk1.8\jre\lib\ext\jfxrt.jar;D:\it\jdk1.8\jre\lib\ext\localedata.jar;D:\it\jdk1.8\jre\lib\ext\nashorn.jar;D:\it\jdk1.8\jre\lib\ext\sunec.jar;D:\it\jdk1.8\jre\lib\ext\sunjce_provider.jar;D:\it\jdk1.8\jre\lib\ext\sunmscapi.jar;D:\it\jdk1.8\jre\lib\ext\sunpkcs11.jar;D:\it\jdk1.8\jre\lib\ext\zipfs.jar;D:\it\jdk1.8\jre\lib\javaws.jar;D:\it\jdk1.8\jre\lib\jce.jar;D:\it\jdk1.8\jre\lib\jfr.jar;D:\it\jdk1.8\jre\lib\jfxswt.jar;D:\it\jdk1.8\jre\lib\jsse.jar;D:\it\jdk1.8\jre\lib\management-agent.jar;D:\it\jdk1.8\jre\lib\plugin.jar;D:\it\jdk1.8\jre\lib\resources.jar;D:\it\jdk1.8\jre\lib\rt.jar;F:\springboot\threaddemo\out\production\threaddemo;D:\it\idea\IntelliJ IDEA 2016.3.3\lib\idea_rt.jar" com.intellij.rt.execution.application.AppMain com.cky.test.Test A & aaaaaaa Exception in thread "A" java.lang.NumberFormatException: For input string: "a" 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 com.cky.bean.Service.testMethod(Service.java:10) at com.cky.thread.ThreadA.run(ThreadA.java:18) B & bbbbb Process finished with exit code 0
线程a出现异常后释放锁,这时线程b可进入执行方法