java - 比较两个列表

Question

我想比较两个列表。由于我们使用 List 编写接口(interface)，它不会从 Object 类继承 equals。我该怎么做？

Answer 1

即使 List 接口(interface)不包含 equals 方法，列表类可能(并且确实)仍然实现 equals 方法.

来自API docs on AbstractList (继承自例如 ArrayList、LinkedList、Vector):

public boolean equals(Object o)

Compares the specified object with this list for equality. Returns true if and only if the specified object is also a list, both lists have the same size, and all corresponding pairs of elements in the two lists are equal.

同样适用于toString、hashCode等方法。

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正如@Pascal 在评论中提到的那样，List 接口(interface)提到了 equals 方法并在文档中声明了以下内容:

The List interface places additional stipulations, beyond those specified in the Collection interface, on the contracts of the iterator, add, remove, equals, and hashCode methods.