MicroCommunity/service-job/src/main/java/com/java110/job/databus/TimeoutTest.java

package com.java110.job.databus;

import java.util.Random;
import java.util.concurrent.*;

public class TimeoutTest {
    private static ExecutorService executorService = Executors.newSingleThreadExecutor();

    /*** @param args*/
    public static void main(String[] args) {
// TODO Auto-generated method stub
        long start = System.currentTimeMillis();
        String result = timeoutMethod(5000);
        System.out.println("方法实际耗时：" + (System.currentTimeMillis() - start) + "毫秒");
        System.out.println("结果：" + result);
        try {
            Thread.sleep(8000);
            long start1 = System.currentTimeMillis();
            String result1 = timeoutMethod(5000);
            System.out.println("方法实际耗时：" + (System.currentTimeMillis() - start1) + "毫秒");
            System.out.println("结果：" + result1);
            executorService.shutdown();
        } catch (
                Exception e) {// TODO: handle exception
        }
    }

    // /*** 有超时时间的方法* @param timeout* @return*/
    private static String timeoutMethod(int timeout) {
        String result = "默认";
        FutureTask<String> futureTask = new FutureTask<>(new Callable<String>() {
            @Override
            public String call() throws Exception {
                return unknowMethod();
            }
        });
        executorService.execute(futureTask);
        try {
            result = futureTask.get(timeout, TimeUnit.MILLISECONDS);
        } catch (InterruptedException | ExecutionException |
                 TimeoutException e) {//e.printStackTrace();
            futureTask.cancel(true);
            result = "默认";
        }
        return result;
    }

    /*** 这个方法的耗时不确定* @return*/
    private static String unknowMethod() {
        Random random = new Random();
        int time = 10000;
        System.out.println("任务将耗时： " + time + "毫秒");
        try {
            Thread.sleep(time);
        } catch (Exception e) {// TODO: handle exception
        }
        return "获得方法执行后的返回值";
    }
}