如何在Java中编写Composition和Aggregation

本文介绍了如何在Java中编写Composition和Aggregation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

我想知道如何在java中识别组合和聚合代码。我有C ++代码，但我不明白如何在java中写。

I want to know how to identify composition and aggregation code in java. I have C++ Code, But I don't understand how to write in java.

组合

class A {}; class B { A composited_A; };

通过指针汇总

class A {}; class B { A* pointer_to_A; B(A anA){ pointer_to_A = &anA; }

任何人都可以告诉我如何在JAVA中工作。 （我知道什么是Composition和聚合）};

Can anyone please tell me how both are working in JAVA. (I know what is meant by Composition and aggregation ) };

推荐答案

Java本身根本不区分组成和聚集之间。你不能在Java类型系统中表达引用的所有权的想法 - 如果你明确需要表达所有权，你必须用其他方法（通常只是通过构造一个新对象存储在类的实例中）来表示。

Java itself simply does not make the distinction between composition and aggregation. You cannot express the idea of ownership of a reference in the Java type system – if you explicitly need to express ownership you must denote this with some other means (usually simply by constructing a new object to be stored in the instance of a class).

因为Java有一个GC，内存的所有权不需要表示;内存只由GC拥有和管理。当然，对于其他资源也不是这样，在这里您可能仍然想表达所有权。

Since Java has a GC, ownership for memory doesn’t need to be expressed at all; memory is owned and managed solely by the GC. Of course, the same is not true for other resources and here you might still want to express ownership.