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添加synchronized关键字的使用
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12 files changed

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‎src/main/java/com/chen/api/util/thread/study/chapter2/StringAndSyn/Service.java‎

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package com.chen.api.util.thread.study.chapter2.StringAndSyn;
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/**
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* @author chen weijie
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* @date 2018-04-17 11:41 PM
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*/
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public class Service {
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public static void print(String stringParam) {
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try {
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synchronized (stringParam) {
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while (true) {
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System.out.println(Thread.currentThread().getName());
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Thread.sleep(1000);
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}
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}
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} catch (InterruptedException e) {
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e.printStackTrace();
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}
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}
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}

‎src/main/java/com/chen/api/util/thread/study/chapter2/StringAndSyn/Test.java‎

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package com.chen.api.util.thread.study.chapter2.StringAndSyn;
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/**
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* 两个线程都持有'aa'字符串对象的锁,所以造成B线程不能执行,这就是String常量池带来的问题.
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* 因此在大多数情况下synchronized代码块都不适用String作为锁对象,而要改用其它 比如new Object()
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*
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* @author chen weijie
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* @date 2018-04-17 11:47 PM
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*/
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public class Test {
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public static void main(String[] args) {
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ThreadA threadA = new ThreadA("aa");
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ThreadB threadB = new ThreadB("aa");
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threadA.setName("a");
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threadB.setName("b");
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threadA.start();
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threadB.start();
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}
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}

‎src/main/java/com/chen/api/util/thread/study/chapter2/StringAndSyn/ThreadA.java‎

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package com.chen.api.util.thread.study.chapter2.StringAndSyn;
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/**
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* @author chen weijie
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* @date 2018-04-17 11:43 PM
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*/
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public class ThreadA extends Thread {
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private String param;
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public ThreadA(String param) {
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super();
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this.param = param;
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}
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@Override
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public void run() {
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super.run();
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Service.print(param);
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}
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}

‎src/main/java/com/chen/api/util/thread/study/chapter2/StringAndSyn/ThreadB.java‎

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package com.chen.api.util.thread.study.chapter2.StringAndSyn;
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/**
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* @author chen weijie
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* @date 2018-04-17 11:43 PM
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*/
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public class ThreadB extends Thread {
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private String param;
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public ThreadB(String param) {
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super();
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this.param = param;
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}
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@Override
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public void run() {
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super.run();
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Service.print(param);
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}
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}

‎src/main/java/com/chen/api/util/thread/study/chapter2/deadLockTest/DealThreadTask.java‎

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package com.chen.api.util.thread.study.chapter2.deadLockTest;
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/**
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* @author chen weijie
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* @date 2018-04-18 12:11 AM
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*/
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public class DealThreadTask implements Runnable {
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public String userName;
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public Object lock1 = new Object();
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public Object lock2 = new Object();
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public void setFlag(String userName) {
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this.userName = userName;
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}
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@Override
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public void run() {
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if (userName.equals("a")) {
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synchronized (lock1) {
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System.out.println("userName==" + userName);
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try {
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Thread.sleep(3000);
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} catch (InterruptedException e) {
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e.printStackTrace();
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}
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}
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synchronized (lock2) {
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System.out.println("按lock1--->lock2的代码执行了..");
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}
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}
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if (userName.equals("b")) {
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synchronized (lock2) {
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System.out.println("userName========" + userName);
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try {
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Thread.sleep(3000);
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} catch (InterruptedException e) {
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e.printStackTrace();
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}
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}
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synchronized (lock1) {
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System.out.println("按lock2--->lock1的代码执行了..");
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}
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}
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}
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}

‎src/main/java/com/chen/api/util/thread/study/chapter2/deadLockTest/Test.java‎

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package com.chen.api.util.thread.study.chapter2.deadLockTest;
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/**
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* @author chen weijie
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* @date 2018-04-18 12:18 AM
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*/
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public class Test {
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public static void main(String[] args) {
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DealThreadTask task = new DealThreadTask();
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task.setFlag("a");
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Thread thread1 = new Thread(task);
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thread1.start();
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try {
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Thread.sleep(1000);
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} catch (InterruptedException e) {
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e.printStackTrace();
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}
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Thread thread2 = new Thread(task);
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task.setFlag("b");
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thread2.start();
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}
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}

‎src/main/java/com/chen/api/util/thread/study/chapter2/twoStop/Service.java‎

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package com.chen.api.util.thread.study.chapter2.twoStop;
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/**
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* @author chen weijie
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* @date 2018-04-17 11:56 PM
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*/
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public class Service {
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synchronized public void methodA() {
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System.out.println("methodA begin..");
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boolean isContinueRun = true;
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while (isContinueRun) {
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}
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System.out.println("methodA end");
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}
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synchronized public void methodB() {
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System.out.println("methodB begin");
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System.out.println("methodB end");
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}
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}

‎src/main/java/com/chen/api/util/thread/study/chapter2/twoStop/Test.java‎

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package com.chen.api.util.thread.study.chapter2.twoStop;
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/**
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* @author chen weijie
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* @date 2018-04-18 12:00 AM
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*/
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public class Test {
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public static void main(String[] args) {
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Service service = new Service();
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ThreadA threadA = new ThreadA(service);
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ThreadB threadB = new ThreadB(service);
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threadA.setName("a");
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threadB.setName("b");
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threadA.start();
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threadB.start();
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}
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}

‎src/main/java/com/chen/api/util/thread/study/chapter2/twoStop/ThreadA.java‎

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package com.chen.api.util.thread.study.chapter2.twoStop;
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/**
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* @author chen weijie
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* @date 2018-04-17 11:58 PM
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*/
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public class ThreadA extends Thread {
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private Service service;
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public ThreadA(Service service) {
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super();
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this.service = service;
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}
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@Override
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public void run() {
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super.run();
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service.methodA();
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}
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}

‎src/main/java/com/chen/api/util/thread/study/chapter2/twoStop/ThreadB.java‎

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package com.chen.api.util.thread.study.chapter2.twoStop;
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/**
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* @author chen weijie
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* @date 2018-04-17 11:58 PM
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*/
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public class ThreadB extends Thread {
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private Service service;
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public ThreadB(Service service) {
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super();
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this.service = service;
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}
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@Override
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public void run() {
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super.run();
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service.methodA();
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}
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}

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