Overriding follow the convention for the hashCode() method that states, the equal object must have equal hash code. Remember: When we override the equals() method, it is necessary to override the hashCode() method. In short, for any non-null reference say x and y, it returns true if and only if both references refer to the same object. For any non-null reference x, x.equals(null) returns false.It does not provide any information used in the comparison. Consistent: If the two non-null references are x and y, the multiple calling of x.equals(y) constantly returns either true or false.Transitive: If the three non-null references are x, y, and z, x.equals(z) will also return true if x.equals(y) and y.equals(z) both returns true.Symmetric: If the two non-null references are x and y, x.equals(y) will return true if and only if y.equals(x) return true.Reflexive: If x is a non-null reference, the calling of x.equals(x) must return true.It is also possible that an object is equal to another given object, then the equals() method follow the equivalence relation to compare the objects. It returns true if the objects are equal, else returns false. The method parses a reference object as a parameter.

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