在 java 映射中搜索对象
我是 Java 新手，我正在使用 Map 类及其派生类。
我只是想知道如何在其中找到元素。仅执行指针/引用检查吗？
假设我有一个 TreeMap。如果我有一个对象x，我希望你搜索一个整数v，使其键“等于”x，即使它们是MyObject 类的 2 个独立实例，因此有 2 个不同的指针。
是否有任何方法（接口/超类的方法）可以执行此类操作？
提前致谢。
I am new to Java, I was working with Map class and its derivatives.
I was just wondering about how elements are found inside them. Is only a pointer/reference check performed?
Let's say I have a TreeMap<MyObject, Integer>. If I have an object x i would like you to search an integer v such that its key is "equal" to x even if they are 2 separate instances of the class MyObject, hence 2 different pointers.
Is there any method (of an interface/superclass too) which can it do such operation?
Thanks in advance.
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Map 及其实现中涉及比较的所有方法都使用对象的“equals”方法。如果您尝试将键+值添加到已经包含与它比较的键的条目的Map，则新的键+值将替换旧的键+值。
请参阅文档：
如果实现可以通过其他方式（例如比较哈希码）确定键“不相等”，则它可能不会执行任何等于比较。
All the methods that involve comparisons in Map and its implementations make use of the 'equals' method for the objects. If you attempt to add a key+value to a Map which already contains aentry with a key that would compare equals to it, then the new key+value replaces the old one.
See the documentation:
The implementation may not execute any equals comparison if it can determine that the keys are 'unequal' through some other means, such as comparing hashcodes.
在您的示例中，您将执行
get(x)将迭代您的keys()并返回与aKey.equals(x ）。In your example, you would do
The
get(x)will iterate over yourkeys()and returning the integer value for the key matchingaKey.equals(x).在大多数情况下，
Map由哈希表支持，并且与HashMap非常相似。 TreeMap 通过在树上上下移动指针来提供每个节点的更多信息，但查找仍然通过哈希完成（我相信）In most cases,
Maps are backed by a hash table, and are very similar to aHashMap.TreeMapgives a bit more information with each node by having pointers up and down the tree, but lookups are still done via hashes (I believe)