是否可以使用 whenComplete(...) 向 CompletableFuture 添加多个操作?

Is it possible to add multiple actions to a CompletableFuture with whenComplete(...)?

class CompletableFuture 允许添加一个动作,在调用 complete(...) 之后未来完成时调用。

我可以使用whenComplete(...)添加多个BiConsumer操作用于完成未来时执行并且在调用complete(...)方法时全部执行吗?

是的,所有 BiConsumer 操作都被添加,并且在调用 complete(...) 时以相反的添加顺序执行。

演示这一点的示例可能如下所示:

public class Application {
    public static void main(String[] args) {
        System.out.println("My tests ...");
        CompletableFuture<String> futureString = new CompletableFuture<String>();
        futureString.whenComplete((s,e)->System.out.println("one " + s));
        futureString.whenComplete((s,e)->System.out.println("two " + s));
        futureString.whenComplete((s,e)->System.out.println("three " + s));
        System.out.println("do something else; "+ futureString.isDone());
        futureString.complete("step(s)");
        System.out.println("Done " + futureString.isDone());
    }
}

当运行此程序时,打印结果如下:

My tests ...
do something else; false 
three step(s)
two step(s)
one step(s)
Done true