Copying a HashMap in Java

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灰色年华
灰色年华 2020-11-29 22:02

I am trying to keep a temporary container of a class that contains member :

HashMap myobjectHashMap

A class called my

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  •  执念已碎
    2020-11-29 22:33

    The difference is that in C++ your object is on the stack, whereas in Java, your object is in the heap. If A and B are Objects, any time in Java you do:

    B = A
    

    A and B point to the same object, so anything you do to A you do to B and vice versa.

    Use new HashMap() if you want two different objects.

    And you can use Map.putAll(...) to copy data between two Maps.

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