标签：when AC 源码 interrupt syn code log nbsp any
先说Future, 它用来描述一个异步计算的结果。isDone方法可以用来检查计算是否完成，get方法可以用来获取结果，直到完成前一直阻塞当前线程，cancel方法可以取消任务。而对于结果的获取，只能通过阻塞(get())或者轮询的方式[while(!isDone)]. 阻塞的方式违背了异步编程的理念，轮询的方式耗费无谓的CPU资源（CPU空转）。于是，CompletableFuture应运而生。
后面介绍的源码都会以下面的用例为切入点，循着调用轨迹理解源码。
1 public void whenComplete() { 2 CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 100); 3 future.whenComplete((l, r) -> System.out.println(l)); 4 } 5 6 public void thenApply() { 7 CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 100); 8 future.thenApply(i -> -i); 9 } 10 11 public void thenAccept() { 12 CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 100); 13 future.thenAccept(System.out::println); 14 } 15 16 public void thenRun() { 17 CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 100); 18 future.thenRun(() -> System.out.println("Done")); 19 } 20 21 public void thenAcceptBoth() { 22 CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 100); 23 CompletableFuture<Integer> other = CompletableFuture.supplyAsync(() -> 200); 24 future.thenAcceptBoth(other, (x, y) -> System.out.println(x + y)); 25 } 26 27 public void acceptEither() { 28 CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 100); 29 CompletableFuture<Integer> other = CompletableFuture.supplyAsync(() -> 200); 30 future.acceptEither(other, System.out::println); 31 32 } 33 34 public void allOf() { 35 CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 100); 36 CompletableFuture<Integer> second = CompletableFuture.supplyAsync(() -> 200); 37 CompletableFuture<Integer> third = CompletableFuture.supplyAsync(() -> 300); 38 CompletableFuture.allOf(future, second, third); 39 40 } 41 42 public void anyOf() throws InterruptedException, ExecutionException { 43 CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 100); 44 CompletableFuture<Integer> second = CompletableFuture.supplyAsync(() -> 200); 45 CompletableFuture<Integer> third = CompletableFuture.supplyAsync(() -> 300); 46 CompletableFuture.anyOf(future, second, third); 47 }
行文至此结束。
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标签：when AC 源码 interrupt syn code log nbsp any
原文地址：https://www.cnblogs.com/aniao/p/aniao_cf.html
