java 使用线程池执行任务，最后汇总结果

女爷i 2024-03-17 11:27 54阅读 0赞

public class CompletableFutureTest {
        public static void main(String[] args) throws ExecutionException, InterruptedException {
            ThreadPoolExecutor executor = new ThreadPoolExecutor(
                    10,
                    10,
                    1L,
                    TimeUnit.SECONDS,
                    new ArrayBlockingQueue<>(100),
                    new ThreadPoolExecutor.CallerRunsPolicy());
            //CompletableFuture使用默认创建的线程池
            test1();
            //自定义线程池方式
            test2(executor);
        }
    
        public static void test1() throws ExecutionException, InterruptedException {
            CompletableFuture<List<Integer>> a = CompletableFuture.supplyAsync(() -> {
                List<Integer> ids = new ArrayList<>();
                for (int i = 0; i < 10; i++) {
                    try {
                        Thread.sleep(200);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    ids.add(i);
                    System.out.println(i);
                }
                return ids;
            });
    
            CompletableFuture<List<Integer>> b = CompletableFuture.supplyAsync(() -> {
                List<Integer> ids = new ArrayList<>();
                for (int i = 0; i < 10; i++) {
                    try {
                        Thread.sleep(200);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    ids.add(i * 10);
                    System.out.println(i * 10);
                }
                return ids;
            });
    
            CompletableFuture<List<Integer>> c = CompletableFuture.supplyAsync(() -> {
                List<Integer> ids = new ArrayList<>();
                for (int i = 0; i < 10; i++) {
                    try {
                        Thread.sleep(200);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    ids.add(i * 100);
                    System.out.println(i * 100);
                }
                return ids;
            });
    
            CompletableFuture.allOf(a, b, c).join();
            List<Integer> aList = a.get();
            List<Integer> bList = b.get();
            List<Integer> cList = c.get();
            System.out.println(aList);
            System.out.println(bList);
            System.out.println(cList);
        }
    
        public static void test2(ThreadPoolExecutor executor) throws ExecutionException, InterruptedException {
            System.out.println("开始执行submit");
            Future<List<Integer>> a = executor.submit(() -> {
                List<Integer> list = new ArrayList<>();
                for (int i = 0; i < 3; i++) {
                   list.add(i);
                    System.out.println(i);
                }
                return list;
            });
            Future<List<Integer>> b = executor.submit(() -> {
                List<Integer> list = new ArrayList<>();
                for (int i = 0; i < 3; i++) {
                    list.add(i * 10);
                    System.out.println(i * 10);
                }
                return list;
            });
            Future<List<Integer>> c = executor.submit(() -> {
                List<Integer> list = new ArrayList<>();
                for (int i = 0; i < 3; i++) {
                    list.add(i * 100);
                    System.out.println(i * 100);
                }
                return list;
            });
            System.out.println("跳过执行----");
            List<Integer> aList = a.get();
            List<Integer> bList = b.get();
            List<Integer> cList = c.get();
            System.out.println("submit.get");
            System.out.println(aList);
            System.out.println(bList);
            System.out.println(cList);
        }
    }