JAVA高级面试进阶训练营视频教程

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一，创建一个线程池

其中：

public void rejectedExecution(Runnable r, ThreadPoolExecutor executor)

饱和策略执行时的具体逻辑。

protected void afterExecute(Runnable r, Throwable t)

异常后的具体逻辑。

package com.kintech.scanAF.common;
 
import com.kintech.common.utils.log.LogerHelper;
import java.util.concurrent.*;
 
/**
 * @author Tyler
 * @date 2019/9/12
 */
public class ThreadHelper {
    //初始化线程池
    private static final ExecutorService pool = new ThreadPoolExecutor(
            2, 
            5, 
            60,
            TimeUnit.SECONDS, 
            new ArrayBlockingQueue<Runnable>(10),
            Executors.defaultThreadFactory(), 
            new ThreadPoolExecutor.DiscardPolicy(){
        public void rejectedExecution(Runnable r, ThreadPoolExecutor executor) {
            LogerHelper.Write("--- "+this.getClass().getName()+"\r\n--- 队列已满，请稍后再来");
        }
    })
    {
        @Override
        protected void afterExecute(Runnable r, Throwable t) {
            super.afterExecute(r, t);
            LogerHelper.Write(t.getMessage());
            System.out.println(t.getMessage());
        }
    };
 
    /**
     * 执行线程池方法（方法在RunnableFunc文件夹中）
     * @param run
     */
    public static void execute(Runnable run)
    {
        pool.execute(run);
    }
    /**
     * 执行线程池方法（方法在RunnableFunc文件夹中）
     * @param run
     */
    public static Future<?> submit(Runnable run)
    {
        Future<?> future = pool.submit(run);
        return future;
    }
 
}

线程池的参数介绍：

public ThreadPoolExecutor(
  int corePoolSize, // 线程数量
  int maximumPoolSize, // 最大线程数量
  long keepAliveTime, // 线程存活时间
  TimeUnit unit, //时间单位
  BlockingQueue<Runnable> workQueue, // 任务队列
  ThreadFactory threadFactory, // 线程创建工厂，可以给线程起名字
  RejectedExecutionHandler handler) // 饱和策略

二，创建任务

package com.kintech.scanAF.common.RunnableFunc;
 
 
/**
 * @author Tyler
 * @date 2019/9/12
 */
public class Test implements Runnable {
    private String a;
    public Test(String a)
    {
        this.a=a;
    }
 
    @Override
    public void run() {
        try
        {
            throw new RuntimeException( "Service has error !");
        }
        catch (Exception e) {
            throw e;
        }
        finally
        {
            a=null;
        }
 
    }
}

三，调用并获取异常

public void MainTest(String a) throws IOException {
        Future<?> future = ThreadHelper.submit(new Test(a));
        try {
            future.get();
        }
        catch (Exception ex)
        {
//记录日志
            LogerHelper.Write(ex.getMessage());
//swing弹窗
            JOptionPane.showMessageDialog(null, ex.getMessage(), "Message", JOptionPane.ERROR_MESSAGE);
        }
 
    }