What is the use of defining equals , compareTo and hashcode methods in a class ? Where are they used ?
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 Q1. What is the use of defining equals , compareTo and hashcode methods in a class ? Where are they used ?Core Java2020-01-09 16:32:57

Ans. equals, compareTo and hashcode are of use when the objects are used within collections.

Equals helps with collections that helps maintaining only unique objects ( like Set )

compare and compareTo helps with collections that helps maintaining objects in order ( TreeSet, TreeMap etc )

hascode helps with collections that facilitates hash searching ( like hashSet, hashMap etc )

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