Question

Please answer the following question in java:

1. Why do we need to override the method public boolean equals(Object ob) in any class?

2. Is public boolean equals(Object ob) is same as public boolean equals(Circle ob)?

Answer 1

1. Why do we need to override the method public boolean equals(Object ob) in any class?

equals(Object ob) method belongs to the object class. so every class will automatically inherit this equals(Object ob) method. Internally this equal method compares two objects based on their reference memory value.

But if we want to compare the object based on the value we want then we override the equals() method.

2. Is public boolean equals(Object ob) is same as public boolean equals(Circle ob)?

equals(Object ob)

the above function will compare object class object to whatever object we calling on it. But equals(Circle ob) function will compare only the same two Circle objects.

OutPut wise even if instead of equals(Circle ob) we write equals(Object ob), it won't create any problem, cause Circle class is child of Object class. But it is not recommended to do that.