Abstract Class Example In Java Constructor

The abstract constructor forces classes that inherit from the class to implement or call the constructor.

Abstract class example in java constructor. This implies that you can be sure that any operations in the constructor of the abstract class will be executed. Java abstract class example code lets see an example where an abstract class name objectsahpe and have one abstract method without body method with the name draw a shape class is to have the main method to access this program. In the above example we have a private constructor named main. Main obj new main.

During this process the constructor is called. All classes have constructors by default. In abstract class can also have constructor because constructors are not used for creating object constructors are used to initialize the data members of a class and abstract class can also have data member and for initialize the data member of abstract class need a constructor if we did not provide the constructor then jvm supply the 0 param or default constructor for. Derived fun called 2 like c an abstract class can contain constructors in java.

Note that the constructor name must match the class name and it cannot have a return type like void. An abstract class can have parameterized constructors and default constructor is always present in an abstract class. Its a very simple and basic example of abstraction in java. Hence the print statement is executed and the variable x is initialized.

Subclass provides that name to superclass while creating a concrete instance of server and overriding abstract method starts. Also note that the constructor is called when the object is created. If you do not create a class constructor yourself java creates one for you. An abstract class can have abstract and non abstract concrete methods and cant be instantiated with inheritance polymorphism abstraction encapsulation exception handling multithreading io streams networking string regex collection jdbc etc.

In this example java program we have an abstract class server which has a constructor with one parameter which accepts the name. For example the following is a valid java program. Read more about abstract class with examples at what is abstract class and abstract method in java with examples github repository the source code of this article available on my github repository at oops concepts tutorial.