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equals&==operator

1. What is difference between == operator and .equals() method?
== Opertor .equals() method
=========================================== ==============================================
-> It is an operator, applicable for both premitives -> It is a method, applicable only for Object types but
     and Object types.      not premitives.
---------------------------------------------------      --------------------------------------------------------------
-> In general == operator meant           -> in general .equals method is used for content comparision.
     for reference/address comparision.    
---------------------------------------------------     ---------------------------------------------------------------------
-> It is not possible to override == operator for -> It is possible to override equals(-) method for content
     content comparision.      comparision.
-------------------------------------------------      -----------------------------------------------------------------------

Note:**.equals method present in object class also meant for reference comparision only based on our requirement we can override fro content comparision.
     ** In string class all wrapper class and all collection classes .equals() is overridden for content comparision.

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