未来与承诺的区别

本文介绍了未来与承诺的区别的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

未来和 promise之间有什么区别？？ 它们都像预留位置

根据 .edu / pipermail / concurrency-interest / 2012-December / 010423.html>此讨论， Promise 终于被调用 CompletableFuture 以包含在Java 8中，以及其javadoc 解释：

未来可以明确完成（设置其值和状态），并可用作完成区，支持完成后触发的依赖函数和动作。

列表中也列出了一个示例：

f.then（（s - > aStringFunction）.sasAsync（s - > ...）;

请注意，最终的API略有不同，但允许类似的异步执行：

CompletableFuture ; String> f = ...; f.thenApply（this :: modifyString）.thenAccept（System.out :: println）;

What's the difference between future and promise? They both act like a placeholder for future results, but where is the main difference?

解决方案

According to this discussion, Promise has finally been called CompletableFuture for inclusion in Java 8, and its javadoc explains:

A Future that may be explicitly completed (setting its value and status), and may be used as a CompletionStage, supporting dependent functions and actions that trigger upon its completion.

An example is also given on the list:

f.then((s -> aStringFunction(s)).thenAsync(s -> ...);

Note that the final API is slightly different but allows similar asynchronous execution:

CompletableFuture<String> f = ...; f.thenApply(this::modifyString).thenAccept(System.out::println);