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在计算机科学中，应用程序编程接口（API）是一个接口，用于定义应用程序可以从库请求服务的方式

In computer science, an application programming interface (API) is an interface that defines the ways by which an application program may request services from libraries

Java包含这些包中的许多库（Swing等），以及 API 是我们请求服务（执行操作等）的接口。

Java contains many libraries in those packages (Swing, etc.), and the API is the interface by which we request services (perform actions, etc.).