Java - Do I need to implement equals and hash code in treemap?

No, you don't.

We don't need to implement equals and hashCode in key object used in TreeMap or HashSet.

TreeMap and HashSet in java works by comparing objets (that's why we have sorted order). If the key is the same than the value is overrided by new value.

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• Java - do we need to implement equals and hash code methods in object used as key in TreeMap (or HashSet)