The reference variable of the Parent class is capable to hold its object reference as well as its child object reference.
In Java, methods are virtual by default (See this for details).
What about non-method members. For example, predict the output of following Java program.
Parent Constructor Child Constructor Reference of Child Type : 10 Reference of Parent Type : 1000
If a parent reference variable is holding the reference of the child class and we have the “value” variable in both the parent and child class, it will refer to the parent class “value” variable, whether it is holding child class object reference. The reference holding the child class object reference will not be able to access the members (functions or variables) of the child class. It is because compiler uses special run-time polymorphism mechanism only for methods.
It is possible to access child data members using parent pointer with typecasting. Please see last example of this for complete code.
This article is contributed by Twinkle Tyagi .If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to email@example.com. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.
- Java.util.BitSet class methods in Java with Examples | Set 2
- Shadowing of static functions in Java
- How does default virtual behavior differ in C++ and Java ?
- How are Java objects stored in memory?
- How are parameters passed in Java?
- Are static local variables allowed in Java?
- final variables in Java
- Default constructor in Java
- Assigning values to static final variables in Java
- Comparison of Exception Handling in C++ and Java
- Does Java support goto?
- Arrays in Java
- Inheritance and constructors in Java
- More restrictive access to a derived class method in Java
- Comparison of static keyword in C++ and Java