Inheritance enables you to extend the functionality of an existing class.
In inheritance, a superclass or a parent class is the one from which another class inherits attributes and behavior. A subclass or child class is a class that inherits attributes and behavior from a superclass.
Note
Th object class is called as a supermost class. Inheritance is applicable only for nonstatic classes.
The following is an example of inheritance in a Java program:
package MyFirstPackage;
class SampleClass1 {
void sampleMethod(){
System.out.println("executing sample method");
}
}
class SampleClass2 extends SampleClass1 {
void sampleMethod1(){
System.out.println("executing sample method 2");
}
}
public class Inhertance {
public static void main(String[] args) {
SampleClass2 methodcall = new SampleClass2();
methodcall.sampleMethod1();
methodcall.sampleMethod();
}
}The output of the preceding code will be as follows:
executing sample method 2 executing sample method
The following is an example of an abstract class in a Java program:
package MyFirstPackage;
abstract class sample_abs {
abstract void abstr_method ();
abstract void abstr_method1 ();
abstract void abstr_method2 ();
abstract void abstr_method3 ();
abstract void abstr_method4 ();
void nonabstr (){
}
}
abstract class sample_abs1 extends sample_abs {
void abstr_method () {
}
void abstr_method1 () {
}
void abstr_method2 () {
}
void abstr_method3 () {
}
public class AbstractClass extends sample_abs1 {
void abstr_method1 () {
}
void abstr_method4 () {
}
public static void main(String[] args) {
System.out.println("Abstract class demo");
}
}The output will be as follows:
Abstract class demo