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Fork/Join框架说明

article 2024/9/25 23:20:18

1.说明

2.ForkJoinPool的说明

3.ForkJoinTask的说明

4.任务的提交方式

5.示例

1.说明

Fork/Join框架使用的是分而治之的一种模式，比如常见的map reduce也是这种模式。

分而治之就是把一个很大的任务拆分成多个毫无关系的小任务，多个线程执行这些小任务。

本质上通过递归处理，将大任务进行拆分执行，如果有返回结果，将结果进行合并返回。

框架包含两个关键操作，Fork（分解）和Join（合并），适用于可以分为多个子问题的计算密集型任务，充分利用多核处理器实现多个线程并行执行，提高执行效率。

框架包含一个线程池（ForkJoinPool）和任务（ForkJoinTask）的概念。在任务内实现任务逻辑，并按照最小任务大小进行分割，然后将任务提交到线程池进行处理。

Fork/Join模式的优点在于他能够充分利用多核处理器的并行性，提高计算效率。但是也存在一些局限性，比如某些问题无法自然的拆分成独立的子任务，任务拆分的过大或者过小导致处理性能差别较大。

2.ForkJoinPool的说明

线程池的线程数默认根据cpu逻辑处理器的个数决定，可以手动设定并发执行的线程数。构造函数如下：

    // 无参构造函数：通常情况下，并发度的默认值为Runtime.availableProcessors()    
    public ForkJoinPool() {
        this(Math.min(MAX_CAP, Runtime.getRuntime().availableProcessors()),
             defaultForkJoinWorkerThreadFactory, null, false);
    }
    // 指定线程池并发度的构造函数
    public ForkJoinPool(int parallelism) {
        this(parallelism, defaultForkJoinWorkerThreadFactory, null, false);
    }
    // 以上两个public构造函数，都将调用如下构造函数
    public ForkJoinPool(int parallelism,
                        ForkJoinWorkerThreadFactory factory,
                        UncaughtExceptionHandler handler,
                        boolean asyncMode) {
        this(checkParallelism(parallelism),
             checkFactory(factory),
             handler,
             asyncMode ? FIFO_QUEUE : LIFO_QUEUE,
             "ForkJoinPool-" + nextPoolId() + "-worker-");
        checkPermission();
    }

（1）parallelism：并行级别，通常默认为 JVM 可用的处理器个数，如下： Runtime.getRuntime().availableProcessors()

（2）factory：用于创建 ForkJoinPool 中使用的线程，ForkJoinPool管理的线程均是扩展自Thread类的ForkJoinWorkerThread类型(里面包含了一个双端队列)。如果你不指定factory，那么将由默认的DefaultForkJoinWorkerThreadFactory负责线程的创建工作。

（3）handler：用于处理工作线程未处理的异常，默认为 null。

（4）asyncMode：用于控制 WorkQueue 的工作模式。当asyncMode为true时，将使用先进先出队列，而为false时则使用后进先出的模式。默认为false，是后进先出模式。

    public static ForkJoinPool commonPool() {
        // assert common != null : "static init error";
        return common;
    }

ForkJoinPool还提供了一个static公共池，对应ForkJoinPool中的static final变量。

ForkJoinPool提供了commonPool()方法，用于获取公共池。

任何未显式提交到指定池（如自定义的池）的ForkJoinTask，都将使用公共池进行处理。

公共池中的线程，在不使用的时候可以被缓慢回收，而后续使用时又可以恢复，因此使用公共池可以减少资源开销

LIFO及任务窃取：

工作窃取指的是当某个线程的任务队列中没有可执行的任务时，从其他线程的任务队列中来窃取任务进行执行，以充分利用工作线程的计算能力，减少线程由于获取不到任务而造成的空间浪费。在ForkJoinPool中，工作任务的队列都采用双端队列容器，通常在使用队列时，我们都是在队尾插入，而在队头消费实现FIFO，而为了工作窃取，采用的LIFO模式，在队尾插入，在队尾进行消费，工作窃取时，从队列头部获取任务进行执行，使用的是FIFO模式。

3.ForkJoinTask的说明

①有返回值的任务RecursiveTask<T>

②没有返回值的任务RecursiveAction

根据需要继承两个类中的一个，重写compute方法，在方法中进行任务的分解和合并，注意要定义好最小任务的大小。

4.任务的提交方式

①execute

提交异步执行，主线程不会等待。

②invoke

等待并获取执行结果，主线程会等待，直至获取线程的执行结果

③submit

提交执行获取Feture结果，主线程不会等待，可以通过Feture获取执行结果

5.示例

package com.test.forkjoin;

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.RecursiveTask;

/**
 * @Author linaibo
 * @Date 2023/11/14 11:25
 * @Version 1.0
 */
public class ForkJoinTest extends RecursiveTask<List<String>> {

    private static final int point = 10;

    private int start;
    private int end;
    private List<String> strList;

    public ForkJoinTest(int start, int end, List<String> strList) {
        this.start = start;
        this.end = end;
        this.strList = strList;
    }

    @Override
    protected List<String> compute() {
        List<String> list = new ArrayList<>();
        if ((end - start) <= point) {
            for (int i = start; i <= end; i++) {
                list.add(strList.get(i).toUpperCase());
                System.out.println("线程：" + Thread.currentThread().getName() + "执行" + i);

            }
        } else {
            int fen = (start + end) / 2;
            ForkJoinTest forkJoinTest1 = new ForkJoinTest(start, fen, strList);
            ForkJoinTest forkJoinTest2 = new ForkJoinTest(fen + 1, end, strList);
            invokeAll(forkJoinTest1, forkJoinTest2);
            List<String> join1 = forkJoinTest1.join();
            List<String> join2 = forkJoinTest2.join();
            list.addAll(join1);
            list.addAll(join2);
        }
        return list;
    }
}

①execute示例

    @Test
    public void testExecute() {
        ForkJoinPool forkJoinPool = new ForkJoinPool(8);
        List<String> strlist = new ArrayList<>();
        for (int i = 0; i < 100; i++) {
            strlist.add("qwe" + i);
        }
        ForkJoinTest forkJoinTest = new ForkJoinTest(0, strlist.size() - 1, strlist);
        forkJoinPool.execute(forkJoinTest);
        System.out.println(forkJoinPool.getPoolSize());
        System.out.println(forkJoinPool.getStealCount());
        System.out.println(forkJoinPool.getActiveThreadCount());
        System.out.println("执行完成");
    }

执行结果：

使用execute，主线程不会等待子线程执行结束。

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com.intellij.rt.junit.JUnitStarter -ideVersion5 -junit4 easyTest,testExecute
1
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执行完成
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Process finished with exit code 0
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②invoke方式

    @Test
    public void test() {
        ForkJoinPool forkJoinPool = new ForkJoinPool(8);
        List<String> strlist = new ArrayList<>();
        for (int i = 0; i < 200; i++) {
            strlist.add("qwe" + i);
        }
        ForkJoinTest forkJoinTest = new ForkJoinTest(0, strlist.size() - 1, strlist);
        List<String> list = forkJoinPool.invoke(forkJoinTest);
        System.out.println(forkJoinPool.getPoolSize());
        System.out.println(forkJoinPool.getStealCount());
        System.out.println(forkJoinPool.getActiveThreadCount());
        System.out.println("执行完成");
        System.out.println(JSON.toJSONString(list));
        forkJoinPool.shutdown();
    }

执行结果

先执行子线程，子线程执行完成之后，进行主线程处理，这是最常用的方式。

线程：ForkJoinPool-1-worker-1执行0
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线程：ForkJoinPool-1-worker-3执行100
线程：ForkJoinPool-1-worker-5执行25
线程：ForkJoinPool-1-worker-5执行26
线程：ForkJoinPool-1-worker-5执行27
线程：ForkJoinPool-1-worker-5执行28
线程：ForkJoinPool-1-worker-2执行50
线程：ForkJoinPool-1-worker-1执行12
线程：ForkJoinPool-1-worker-2执行51
线程：ForkJoinPool-1-worker-1执行13
线程：ForkJoinPool-1-worker-5执行29
线程：ForkJoinPool-1-worker-4执行75
线程：ForkJoinPool-1-worker-7执行19
线程：ForkJoinPool-1-worker-3执行101
线程：ForkJoinPool-1-worker-3执行102
线程：ForkJoinPool-1-worker-7执行20
线程：ForkJoinPool-1-worker-7执行21
线程：ForkJoinPool-1-worker-7执行22
线程：ForkJoinPool-1-worker-7执行23
线程：ForkJoinPool-1-worker-7执行24
线程：ForkJoinPool-1-worker-4执行76
线程：ForkJoinPool-1-worker-7执行175
线程：ForkJoinPool-1-worker-5执行30
线程：ForkJoinPool-1-worker-5执行31
线程：ForkJoinPool-1-worker-5执行32
线程：ForkJoinPool-1-worker-5执行33
线程：ForkJoinPool-1-worker-1执行14
线程：ForkJoinPool-1-worker-2执行52
线程：ForkJoinPool-1-worker-1执行15
线程：ForkJoinPool-1-worker-7执行176
线程：ForkJoinPool-1-worker-4执行77
线程：ForkJoinPool-1-worker-6执行150
线程：ForkJoinPool-1-worker-6执行151
线程：ForkJoinPool-1-worker-6执行152
线程：ForkJoinPool-1-worker-6执行153
线程：ForkJoinPool-1-worker-6执行154
线程：ForkJoinPool-1-worker-3执行103
线程：ForkJoinPool-1-worker-0执行88
线程：ForkJoinPool-1-worker-3执行104
线程：ForkJoinPool-1-worker-3执行105
线程：ForkJoinPool-1-worker-3执行106
线程：ForkJoinPool-1-worker-6执行155
线程：ForkJoinPool-1-worker-4执行78
线程：ForkJoinPool-1-worker-4执行79
线程：ForkJoinPool-1-worker-7执行177
线程：ForkJoinPool-1-worker-5执行34
线程：ForkJoinPool-1-worker-1执行16
线程：ForkJoinPool-1-worker-2执行53
线程：ForkJoinPool-1-worker-1执行17
线程：ForkJoinPool-1-worker-1执行18
线程：ForkJoinPool-1-worker-5执行35
线程：ForkJoinPool-1-worker-7执行178
线程：ForkJoinPool-1-worker-4执行80
线程：ForkJoinPool-1-worker-6执行156
线程：ForkJoinPool-1-worker-3执行107
线程：ForkJoinPool-1-worker-3执行108
线程：ForkJoinPool-1-worker-3执行109
线程：ForkJoinPool-1-worker-3执行110
线程：ForkJoinPool-1-worker-3执行111
线程：ForkJoinPool-1-worker-3执行112
线程：ForkJoinPool-1-worker-0执行89
线程：ForkJoinPool-1-worker-3执行113
线程：ForkJoinPool-1-worker-6执行157
线程：ForkJoinPool-1-worker-6执行158
线程：ForkJoinPool-1-worker-4执行81
线程：ForkJoinPool-1-worker-7执行179
线程：ForkJoinPool-1-worker-5执行36
线程：ForkJoinPool-1-worker-5执行37
线程：ForkJoinPool-1-worker-1执行38
线程：ForkJoinPool-1-worker-2执行54
线程：ForkJoinPool-1-worker-2执行55
线程：ForkJoinPool-1-worker-2执行56
线程：ForkJoinPool-1-worker-2执行57
线程：ForkJoinPool-1-worker-2执行58
线程：ForkJoinPool-1-worker-2执行59
线程：ForkJoinPool-1-worker-2执行60
线程：ForkJoinPool-1-worker-2执行61
线程：ForkJoinPool-1-worker-2执行62
线程：ForkJoinPool-1-worker-2执行63
线程：ForkJoinPool-1-worker-2执行64
线程：ForkJoinPool-1-worker-2执行65
线程：ForkJoinPool-1-worker-2执行66
线程：ForkJoinPool-1-worker-2执行67
线程：ForkJoinPool-1-worker-2执行68
线程：ForkJoinPool-1-worker-5执行44
线程：ForkJoinPool-1-worker-7执行180
线程：ForkJoinPool-1-worker-7执行181
线程：ForkJoinPool-1-worker-4执行82
线程：ForkJoinPool-1-worker-6执行159
线程：ForkJoinPool-1-worker-3执行114
线程：ForkJoinPool-1-worker-0执行90
线程：ForkJoinPool-1-worker-0执行91
线程：ForkJoinPool-1-worker-0执行92
线程：ForkJoinPool-1-worker-0执行93
线程：ForkJoinPool-1-worker-3执行115
线程：ForkJoinPool-1-worker-6执行160
线程：ForkJoinPool-1-worker-4执行83
线程：ForkJoinPool-1-worker-7执行182
线程：ForkJoinPool-1-worker-7执行183
线程：ForkJoinPool-1-worker-7执行184
线程：ForkJoinPool-1-worker-7执行185
线程：ForkJoinPool-1-worker-7执行186
线程：ForkJoinPool-1-worker-7执行187
线程：ForkJoinPool-1-worker-5执行45
线程：ForkJoinPool-1-worker-5执行46
线程：ForkJoinPool-1-worker-5执行47
线程：ForkJoinPool-1-worker-5执行48
线程：ForkJoinPool-1-worker-5执行49
线程：ForkJoinPool-1-worker-2执行69
线程：ForkJoinPool-1-worker-1执行39
线程：ForkJoinPool-1-worker-1执行40
线程：ForkJoinPool-1-worker-1执行41
线程：ForkJoinPool-1-worker-2执行70
线程：ForkJoinPool-1-worker-2执行71
线程：ForkJoinPool-1-worker-1执行42
线程：ForkJoinPool-1-worker-7执行188
线程：ForkJoinPool-1-worker-4执行84
线程：ForkJoinPool-1-worker-4执行85
线程：ForkJoinPool-1-worker-4执行86
线程：ForkJoinPool-1-worker-4执行87
线程：ForkJoinPool-1-worker-6执行161
线程：ForkJoinPool-1-worker-6执行162
线程：ForkJoinPool-1-worker-6执行163
线程：ForkJoinPool-1-worker-6执行164
线程：ForkJoinPool-1-worker-6执行165
线程：ForkJoinPool-1-worker-6执行166
线程：ForkJoinPool-1-worker-6执行167
线程：ForkJoinPool-1-worker-6执行168
线程：ForkJoinPool-1-worker-3执行116
线程：ForkJoinPool-1-worker-0执行94
线程：ForkJoinPool-1-worker-3执行117
线程：ForkJoinPool-1-worker-6执行169
线程：ForkJoinPool-1-worker-7执行189
线程：ForkJoinPool-1-worker-7执行190
线程：ForkJoinPool-1-worker-7执行191
线程：ForkJoinPool-1-worker-7执行192
线程：ForkJoinPool-1-worker-7执行193
线程：ForkJoinPool-1-worker-1执行43
线程：ForkJoinPool-1-worker-2执行72
线程：ForkJoinPool-1-worker-7执行194
线程：ForkJoinPool-1-worker-6执行170
线程：ForkJoinPool-1-worker-3执行118
线程：ForkJoinPool-1-worker-0执行95
线程：ForkJoinPool-1-worker-3执行119
线程：ForkJoinPool-1-worker-3执行120
线程：ForkJoinPool-1-worker-3执行121
线程：ForkJoinPool-1-worker-3执行122
线程：ForkJoinPool-1-worker-3执行123
线程：ForkJoinPool-1-worker-3执行124
线程：ForkJoinPool-1-worker-6执行171
线程：ForkJoinPool-1-worker-7执行195
线程：ForkJoinPool-1-worker-7执行196
线程：ForkJoinPool-1-worker-7执行197
线程：ForkJoinPool-1-worker-7执行198
线程：ForkJoinPool-1-worker-7执行199
线程：ForkJoinPool-1-worker-5执行125
线程：ForkJoinPool-1-worker-7执行144
线程：ForkJoinPool-1-worker-7执行145
线程：ForkJoinPool-1-worker-7执行146
线程：ForkJoinPool-1-worker-7执行147
线程：ForkJoinPool-1-worker-7执行148
线程：ForkJoinPool-1-worker-7执行149
线程：ForkJoinPool-1-worker-2执行73
线程：ForkJoinPool-1-worker-7执行132
线程：ForkJoinPool-1-worker-7执行133
线程：ForkJoinPool-1-worker-7执行134
线程：ForkJoinPool-1-worker-7执行135
线程：ForkJoinPool-1-worker-7执行136
线程：ForkJoinPool-1-worker-7执行137
线程：ForkJoinPool-1-worker-5执行126
线程：ForkJoinPool-1-worker-5执行127
线程：ForkJoinPool-1-worker-5执行128
线程：ForkJoinPool-1-worker-5执行129
线程：ForkJoinPool-1-worker-6执行172
线程：ForkJoinPool-1-worker-3执行138
线程：ForkJoinPool-1-worker-0执行96
线程：ForkJoinPool-1-worker-0执行97
线程：ForkJoinPool-1-worker-0执行98
线程：ForkJoinPool-1-worker-0执行99
线程：ForkJoinPool-1-worker-3执行139
线程：ForkJoinPool-1-worker-6执行173
线程：ForkJoinPool-1-worker-5执行130
线程：ForkJoinPool-1-worker-2执行74
线程：ForkJoinPool-1-worker-5执行131
线程：ForkJoinPool-1-worker-6执行174
线程：ForkJoinPool-1-worker-3执行140
线程：ForkJoinPool-1-worker-3执行141
线程：ForkJoinPool-1-worker-3执行142
线程：ForkJoinPool-1-worker-3执行143
8
12
0
执行完成
["QWE0","QWE1","QWE2","QWE3","QWE4","QWE5","QWE6","QWE7","QWE8","QWE9","QWE10","QWE11","QWE12","QWE13","QWE14","QWE15","QWE16","QWE17","QWE18","QWE19","QWE20","QWE21","QWE22","QWE23","QWE24","QWE25","QWE26","QWE27","QWE28","QWE29","QWE30","QWE31","QWE32","QWE33","QWE34","QWE35","QWE36","QWE37","QWE38","QWE39","QWE40","QWE41","QWE42","QWE43","QWE44","QWE45","QWE46","QWE47","QWE48","QWE49","QWE50","QWE51","QWE52","QWE53","QWE54","QWE55","QWE56","QWE57","QWE58","QWE59","QWE60","QWE61","QWE62","QWE63","QWE64","QWE65","QWE66","QWE67","QWE68","QWE69","QWE70","QWE71","QWE72","QWE73","QWE74","QWE75","QWE76","QWE77","QWE78","QWE79","QWE80","QWE81","QWE82","QWE83","QWE84","QWE85","QWE86","QWE87","QWE88","QWE89","QWE90","QWE91","QWE92","QWE93","QWE94","QWE95","QWE96","QWE97","QWE98","QWE99","QWE100","QWE101","QWE102","QWE103","QWE104","QWE105","QWE106","QWE107","QWE108","QWE109","QWE110","QWE111","QWE112","QWE113","QWE114","QWE115","QWE116","QWE117","QWE118","QWE119","QWE120","QWE121","QWE122","QWE123","QWE124","QWE125","QWE126","QWE127","QWE128","QWE129","QWE130","QWE131","QWE132","QWE133","QWE134","QWE135","QWE136","QWE137","QWE138","QWE139","QWE140","QWE141","QWE142","QWE143","QWE144","QWE145","QWE146","QWE147","QWE148","QWE149","QWE150","QWE151","QWE152","QWE153","QWE154","QWE155","QWE156","QWE157","QWE158","QWE159","QWE160","QWE161","QWE162","QWE163","QWE164","QWE165","QWE166","QWE167","QWE168","QWE169","QWE170","QWE171","QWE172","QWE173","QWE174","QWE175","QWE176","QWE177","QWE178","QWE179","QWE180","QWE181","QWE182","QWE183","QWE184","QWE185","QWE186","QWE187","QWE188","QWE189","QWE190","QWE191","QWE192","QWE193","QWE194","QWE195","QWE196","QWE197","QWE198","QWE199"]

③submit方式

    @Test
    public void testSubmit() throws ExecutionException, InterruptedException {
        ForkJoinPool forkJoinPool = new ForkJoinPool(8);
        List<String> strlist = new ArrayList<>();
        for (int i = 0; i < 100; i++) {
            strlist.add("qwe" + i);
        }
        ForkJoinTest forkJoinTest = new ForkJoinTest(0, strlist.size() - 1, strlist);
        ForkJoinTask<List<String>> submit = forkJoinPool.submit(forkJoinTest);
        System.out.println(forkJoinPool.getPoolSize());
        System.out.println(forkJoinPool.getStealCount());
        System.out.println(forkJoinPool.getActiveThreadCount());
        System.out.println(submit.get());
        System.out.println("执行完成");
    }

执行结果

主线程不会等待，执行get方法时，会等待子线程执行完成。

1
0
1
线程：ForkJoinPool-1-worker-1执行0
线程：ForkJoinPool-1-worker-1执行1
线程：ForkJoinPool-1-worker-1执行2
线程：ForkJoinPool-1-worker-1执行3
线程：ForkJoinPool-1-worker-1执行4
线程：ForkJoinPool-1-worker-1执行5
线程：ForkJoinPool-1-worker-1执行6
线程：ForkJoinPool-1-worker-1执行7
线程：ForkJoinPool-1-worker-1执行8
线程：ForkJoinPool-1-worker-1执行9
线程：ForkJoinPool-1-worker-1执行10
线程：ForkJoinPool-1-worker-1执行11
线程：ForkJoinPool-1-worker-1执行12
线程：ForkJoinPool-1-worker-3执行25
线程：ForkJoinPool-1-worker-3执行26
线程：ForkJoinPool-1-worker-4执行75
线程：ForkJoinPool-1-worker-4执行76
线程：ForkJoinPool-1-worker-2执行50
线程：ForkJoinPool-1-worker-3执行27
线程：ForkJoinPool-1-worker-5执行19
线程：ForkJoinPool-1-worker-6执行38
线程：ForkJoinPool-1-worker-2执行51
线程：ForkJoinPool-1-worker-1执行13
线程：ForkJoinPool-1-worker-4执行77
线程：ForkJoinPool-1-worker-0执行88
线程：ForkJoinPool-1-worker-1执行14
线程：ForkJoinPool-1-worker-7执行63
线程：ForkJoinPool-1-worker-2执行52
线程：ForkJoinPool-1-worker-6执行39
线程：ForkJoinPool-1-worker-5执行20
线程：ForkJoinPool-1-worker-3执行28
线程：ForkJoinPool-1-worker-5执行21
线程：ForkJoinPool-1-worker-6执行40
线程：ForkJoinPool-1-worker-2执行53
线程：ForkJoinPool-1-worker-7执行64
线程：ForkJoinPool-1-worker-1执行15
线程：ForkJoinPool-1-worker-0执行89
线程：ForkJoinPool-1-worker-4执行78
线程：ForkJoinPool-1-worker-0执行90
线程：ForkJoinPool-1-worker-1执行16
线程：ForkJoinPool-1-worker-7执行65
线程：ForkJoinPool-1-worker-2执行54
线程：ForkJoinPool-1-worker-6执行41
线程：ForkJoinPool-1-worker-5执行22
线程：ForkJoinPool-1-worker-3执行29
线程：ForkJoinPool-1-worker-5执行23
线程：ForkJoinPool-1-worker-6执行42
线程：ForkJoinPool-1-worker-2执行55
线程：ForkJoinPool-1-worker-7执行66
线程：ForkJoinPool-1-worker-1执行17
线程：ForkJoinPool-1-worker-0执行91
线程：ForkJoinPool-1-worker-4执行79
线程：ForkJoinPool-1-worker-0执行92
线程：ForkJoinPool-1-worker-0执行93
线程：ForkJoinPool-1-worker-1执行18
线程：ForkJoinPool-1-worker-7执行67
线程：ForkJoinPool-1-worker-2执行56
线程：ForkJoinPool-1-worker-2执行57
线程：ForkJoinPool-1-worker-6执行43
线程：ForkJoinPool-1-worker-5执行24
线程：ForkJoinPool-1-worker-3执行30
线程：ForkJoinPool-1-worker-5执行69
线程：ForkJoinPool-1-worker-6执行44
线程：ForkJoinPool-1-worker-6执行45
线程：ForkJoinPool-1-worker-6执行46
线程：ForkJoinPool-1-worker-6执行47
线程：ForkJoinPool-1-worker-6执行48
线程：ForkJoinPool-1-worker-6执行49
线程：ForkJoinPool-1-worker-2执行58
线程：ForkJoinPool-1-worker-7执行68
线程：ForkJoinPool-1-worker-0执行94
线程：ForkJoinPool-1-worker-4执行80
线程：ForkJoinPool-1-worker-0执行95
线程：ForkJoinPool-1-worker-2执行59
线程：ForkJoinPool-1-worker-6执行82
线程：ForkJoinPool-1-worker-5执行70
线程：ForkJoinPool-1-worker-1执行32
线程：ForkJoinPool-1-worker-3执行31
线程：ForkJoinPool-1-worker-1执行33
线程：ForkJoinPool-1-worker-1执行34
线程：ForkJoinPool-1-worker-5执行71
线程：ForkJoinPool-1-worker-6执行83
线程：ForkJoinPool-1-worker-2执行60
线程：ForkJoinPool-1-worker-0执行96
线程：ForkJoinPool-1-worker-4执行81
线程：ForkJoinPool-1-worker-0执行97
线程：ForkJoinPool-1-worker-0执行98
线程：ForkJoinPool-1-worker-0执行99
线程：ForkJoinPool-1-worker-2执行61
线程：ForkJoinPool-1-worker-2执行62
线程：ForkJoinPool-1-worker-6执行84
线程：ForkJoinPool-1-worker-5执行72
线程：ForkJoinPool-1-worker-1执行35
线程：ForkJoinPool-1-worker-5执行73
线程：ForkJoinPool-1-worker-6执行85
线程：ForkJoinPool-1-worker-5执行74
线程：ForkJoinPool-1-worker-1执行36
线程：ForkJoinPool-1-worker-1执行37
线程：ForkJoinPool-1-worker-6执行86
线程：ForkJoinPool-1-worker-6执行87
[QWE0, QWE1, QWE2, QWE3, QWE4, QWE5, QWE6, QWE7, QWE8, QWE9, QWE10, QWE11, QWE12, QWE13, QWE14, QWE15, QWE16, QWE17, QWE18, QWE19, QWE20, QWE21, QWE22, QWE23, QWE24, QWE25, QWE26, QWE27, QWE28, QWE29, QWE30, QWE31, QWE32, QWE33, QWE34, QWE35, QWE36, QWE37, QWE38, QWE39, QWE40, QWE41, QWE42, QWE43, QWE44, QWE45, QWE46, QWE47, QWE48, QWE49, QWE50, QWE51, QWE52, QWE53, QWE54, QWE55, QWE56, QWE57, QWE58, QWE59, QWE60, QWE61, QWE62, QWE63, QWE64, QWE65, QWE66, QWE67, QWE68, QWE69, QWE70, QWE71, QWE72, QWE73, QWE74, QWE75, QWE76, QWE77, QWE78, QWE79, QWE80, QWE81, QWE82, QWE83, QWE84, QWE85, QWE86, QWE87, QWE88, QWE89, QWE90, QWE91, QWE92, QWE93, QWE94, QWE95, QWE96, QWE97, QWE98, QWE99]
执行完成

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