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Java stores objects in a HashMap using an element field

I have a series of objects that contain a field name, and I want to save them in a HashMap, with the key of each object being name. Is there a way to do this, so changing the field of an object namealso changes the key in the HashMap (and even vice versa).

(is it possible to have a bilingual link in Java, so the key refers to a field name(which refers to String)).

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5 answers

This is not supported by any native functionality.

What you need to do is have a special method somewhere like

public static void updateName(String oldname, String newname, Map<String,MyObject> map) {
    synchronized(map) {
        MyObject obj = map.remove(oldname);
        obj.setName(newname);
        map.put(newname,obj);
    }
}

And document everything correctly so that the developers know that they are very careful when changing the name.

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