Object class has following five non final methods.
1. clone()
2. equals(Object obj)
3. finalize()
4. hashCode()
5. toString()
Every Java class has Object as a superclass so by default all above methods are provided in every java class. In this article we will discuss in detail the concepts of equals() and hashCode() method. We will discuss why it is necessary to override these methods and how we can override them.
Default implementation of equals() in Object class
The default version of equals method present in the Object class has the same behavior as the == operator which in turn simply checks if two reference variables are referring the same objects.Consider x and y, two object references, then x.equals(y) comparing the memory addresses of the objects referenced by x and y (i.e. not the data of the objects).
1. clone()
2. equals(Object obj)
3. finalize()
4. hashCode()
5. toString()
Every Java class has Object as a superclass so by default all above methods are provided in every java class. In this article we will discuss in detail the concepts of equals() and hashCode() method. We will discuss why it is necessary to override these methods and how we can override them.
Default implementation of equals() in Object class
The default version of equals method present in the Object class has the same behavior as the == operator which in turn simply checks if two reference variables are referring the same objects.Consider x and y, two object references, then x.equals(y) comparing the memory addresses of the objects referenced by x and y (i.e. not the data of the objects).
