java_ExecutorService, CompletionService - 有返回值并行工作方式

package com.demo.test3;

import java.util.ArrayList;

import java.util.List;

import java.util.Random;

import java.util.concurrent.Callable;

import java.util.concurrent.ExecutionException;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

import java.util.concurrent.Future;

/**

 * @author QQ: 1236897

 *

 */

//工作顺序(0000)和(aaaa,bbbb,cccc,dddd)并行， (aaaa),(bbbb),(cccc),(dddd) 为串行出现

public class DemoTEST {

    public static void main(String[] args) {

        final ThreadService service = new ThreadService();

        service.renderPage();

    }

}

class ThreadService {

    private final ExecutorService executor = Executors.newCachedThreadPool();

    public void renderPage() {

        final List<String> list = new ArrayList<String>();

        list.add("aaaa");

        list.add("bbbb");

        list.add("ccccc");

        list.add("dddddd");

        Callable<List<String>> task = new Callable<List<String>>() {

            @Override

            public List<String> call() throws Exception {

                List<String> result = new ArrayList<String>();

                for (String str : list) {

                    System.out.println("input to result.....");

                    Random r = new Random();

                    double d2 = r.nextDouble() * 5;

                    Thread.sleep(1000*(int)d2);

                    result.add(str);

                }

                return result;

            }

        };

        Future<List<String>> future = executor.submit(task);

        System.out.println("000000000 - "+"=======此处和task 同时并行====================");

        try {

            List<String> res = future.get();

            for (String s : res) {

                System.out.println(s+"--"+Thread.currentThread().getName());

            }

        } catch (InterruptedException e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        } catch (ExecutionException e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        }

        executor.shutdown();

    }

}

//==============================================================================================

package com.demo.test4;

import java.util.ArrayList;

import java.util.List;

import java.util.Random;

import java.util.concurrent.Callable;

import java.util.concurrent.CompletionService;

import java.util.concurrent.ExecutionException;

import java.util.concurrent.ExecutorCompletionService;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

import java.util.concurrent.Future;

/**

 * @author QQ: 1236897

 *

 */

//工作方式 - (0000)和(aaaa,bbbb,cccc,dddd)并行开始，(aaaaa)(bbbbb)(ccccc)(ddddd) 并行工作

public class DemoTest2 {

    /**

     * @param args

     */

    public static void main(String[] args) {

        // TODO Auto-generated method stub

        ThreadService service = new ThreadService();

        service.renderPage();

    }

}

class ThreadService {

    private final ExecutorService executor = Executors.newCachedThreadPool();

    public void renderPage() {

        final List<String> list = new ArrayList<String>();

        list.add("aaaa");

        list.add("bbbb");

        list.add("ccccc");

        list.add("dddddd");

        CompletionService<String> completionService = new ExecutorCompletionService<String>(

                executor);

        for (final String s : list) {

            completionService.submit(new Callable<String>() {

                @Override

                public String call() throws Exception {

                    // TODO Auto-generated method stub

                    Random r = new Random();

                    double d2 = r.nextDouble() * 5;

                    Thread.sleep(1000 * (int) d2);

                    return s;

                }

            });

        }

        System.out.println("00000" + "==========并行开始====");

        try {

            for (int i = 0; i < list.size(); i++) {

                Future<String> str = completionService.take();

                String s = str.get();

                System.out.println(s);

            }

        } catch (InterruptedException e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        } catch (ExecutionException e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        }

    }

}