2019独角兽企业重金招聘Python工程师标准>>> 
下午在调试多线程时发现，虽然确认每次都是将线程池关闭
executor.shutdown();
executor.awaitTermination(1, TimeUnit.SECONDS)但是第二个调用任务进来线程池序号还是增加了，没找到原因。当时想了两种解决方法，第一种是用spring来管理线程池，第二种是使用单列模式。看了下网上关于使用spring管理线程池的代码，考虑到我这个功能并没有这么重量级，需要改配置文件来处理。简单处理，使用单列模式做。
1.创建自定义名称的线程池
package com.demo.thread.test20170811;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.RejectedExecutionHandler;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
/**
* 自定义名称线程池
* @author fsw
*
*/
public class NamedThreadPoolExecutor extends ThreadPoolExecutor{
private String name;
public NamedThreadPoolExecutor(int corePoolSize, int maximumPoolSize,
long keepAliveTime, TimeUnit unit, BlockingQueue workQueue, RejectedExecutionHandler handler) {
super(corePoolSize, maximumPoolSize, keepAliveTime, unit, workQueue, handler);
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
2.创建单列模式
package com.demo.thread.test20170811;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.RejectedExecutionHandler;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.ReentrantLock;
/**
* 线程池管理类
* @author fsw
*
*/
public class SingletonThreadPool {
final NamedThreadPoolExecutor executor = new NamedThreadPoolExecutor(5,5,0,TimeUnit.SECONDS,new ArrayBlockingQueue(5), new RejectedExecutionHandler() {
@Override
public void rejectedExecution(Runnable r, ThreadPoolExecutor executor) {
NamedThreadPoolExecutor namedThreadPoolExe = (NamedThreadPoolExecutor) executor;
try {
System.out.println(namedThreadPoolExe.getName());
executor.getQueue().put(r);
} catch (Exception e) {
}
}
});
private static SingletonThreadPool threadPool = null;
private static ReentrantLock lock = new ReentrantLock();
public static SingletonThreadPool getInstance() {
try {
lock.lock();
if(threadPool == null) {
threadPool = new SingletonThreadPool();
return threadPool;
}
} finally {
lock.unlock();
}
return threadPool;
}
public ExecutorService getExecutorService(String name) {
executor.setName(name);
return executor;
}
public Long getComTaskCount() {
return executor.getCompletedTaskCount();
}
}
3.创建执行任务类
package com.demo.thread.test20170811;
import java.util.concurrent.Callable;
public class Task implements Callable{
@Override
public Void call() throws Exception {
System.out.println(Thread.currentThread().getName());
return null;
}
}
4.测试类
package com.demo.thread.test20170811;
import java.util.concurrent.CompletionService;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorCompletionService;
public class SingletonThreadMain {
public static void main(String[] args) throws InterruptedException, ExecutionException {
final SingletonThreadMain m = new SingletonThreadMain();
m.runMethod("a");
m.runMethod("b");
m.runMethod("c");
}
public void runMethod(final String name) throws InterruptedException, ExecutionException {
SingletonThreadPool threadPool = SingletonThreadPool.getInstance();
CompletionService completionService = new ExecutorCompletionService(
threadPool.getExecutorService(name));
for (int i = 0; i < 100; i++) {
completionService.submit(new Task());
}
for (int i = 0; i < 100; i++) {
completionService.take().get();
}
System.out.println("==================="+SingletonThreadPool.getInstance().getComTaskCount());
}
}
5.执行结果
从执行结果可见，线程池序号一直都是1。问题初步解决，后面遇到问题再更新