Java CompletableFuture组合拼装异步线程任务（2）

Java CompletableFuture组合拼装异步线程任务

 private void seq() throws ExecutionException, InterruptedException { System.out.println("时间1:" + System.currentTimeMillis()); CompletableFuture<String> f1 = CompletableFuture.supplyAsync(new Supplier<String>() { @Override public String get() { try { TimeUnit.SECONDS.sleep(3); } catch (InterruptedException e) { e.printStackTrace(); } return "2018"; } }); System.out.println("时间2:" + System.currentTimeMillis()); CompletableFuture<Integer> f2 = f1.thenApply(new Function<String, Integer>() { @Override public Integer apply(String s) { try { TimeUnit.SECONDS.sleep(3); } catch (InterruptedException e) { e.printStackTrace(); } return Integer.parseInt(s); } }); System.out.println("时间3:" + System.currentTimeMillis()); CompletableFuture<Double> f3 = f2.thenApply(new Function<Integer, Double>() { @Override public Double apply(Integer i) { try { TimeUnit.SECONDS.sleep(3); } catch (InterruptedException e) { e.printStackTrace(); } return (double) i; } }); System.out.println("时间4:" + System.currentTimeMillis()); f3.whenComplete((v, a) -> { System.out.println("v: " + v); System.out.println("a: " + a); }); System.out.println("时间5:" + System.currentTimeMillis()); System.out.println(f3.get()); System.out.println("时间6:" + System.currentTimeMillis()); }

输出结果：

06-12 18:49:08.337 6047-6047/zhangphil.test I/System.out: 时间1:1528800548337 06-12 18:49:08.339 6047-6047/zhangphil.test I/System.out: 时间2:1528800548339 06-12 18:49:08.340 6047-6047/zhangphil.test I/System.out: 时间3:1528800548340 06-12 18:49:08.341 6047-6047/zhangphil.test I/System.out: 时间4:1528800548341 06-12 18:49:08.342 6047-6047/zhangphil.test I/System.out: 时间5:1528800548342 06-12 18:49:17.347 6047-6089/zhangphil.test I/System.out: v: 2018.0 a: null 06-12 18:49:17.347 6047-6047/zhangphil.test I/System.out: 2018.0 06-12 18:49:17.348 6047-6047/zhangphil.test I/System.out: 时间6:1528800557348