What is Difference between equals and hashcode method? -...

The differences between The hashCode() method and The equals() method are as follows:

The hashCode() method	The equals() method
The hashCode() method The hashCode() method returns an integer value, which is referred to as the hash code value of an object. Every Object, at the time of creation assigned with a unique 32-bit, signed int value. This value is the hash code value of that object. The hashCode() method should return the same integer value for the same object for each calling of this method unless the value stored in the object is modified. If two objects are equal(according to equals() method) then the hashCode() method should return the same integer value for both the objects. But, it is not necessary that the hashCode() method will return the distinct result for the objects that are not equal (according to equals() method).	The equals() method The equals() method of Object class checks the equality of the objects and accordingly it returns true or false. The default implementation, as provided by the Object class, checks the equality of the objects on the basis if both references refer to the same object. It does not check the value or state of the objects. But we can override this method to provide our own implementation to compare the state or value of the objects. For any non-null reference variables a, b and c a.equals(a) should always return true. a.equals(b) should return true if and only if b.equals(a) returns true. If a.equals(b) returns true and b.equals(c) returns true then a.equals(c) should return true. Multiple calling of a.equals(b) should consistently return true or consistently return false If the value of the object is not modified for either object. a.equals(null) should return false.

The hashCode() method

The equals() method

The hashCode() method The hashCode() method returns an integer value, which is referred to as the hash code value of an object. Every Object, at the time of creation assigned with a unique 32-bit, signed int value. This value is the hash code value of that object. The hashCode() method should return the same integer value for the same object for each calling of this method unless the value stored in the object is modified. If two objects are equal(according to equals() method) then the hashCode() method should return the same integer value for both the objects. But, it is not necessary that the hashCode() method will return the distinct result for the objects that are not equal (according to equals() method).

The equals() method The equals() method of Object class checks the equality of the objects and accordingly it returns true or false. The default implementation, as provided by the Object class, checks the equality of the objects on the basis if both references refer to the same object. It does not check the value or state of the objects. But we can override this method to provide our own implementation to compare the state or value of the objects. For any non-null reference variables a, b and c a.equals(a) should always return true. a.equals(b) should return true if and only if b.equals(a) returns true. If a.equals(b) returns true and b.equals(c) returns true then a.equals(c) should return true. Multiple calling of a.equals(b) should consistently return true or consistently return false If the value of the object is not modified for either object. a.equals(null) should return false.

What is Difference between equals and hashcode method?

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