Polymorphism is the ability of an object to take on many forms. The most common use of polymorphism in OOP occurs when a parent class reference is used to refer to a child class object.
Methods with the same names in a class are allowed provided each method has a different signature. Overloading can be done in the following ways:
Number of arguments
Type of arguments
Position of arguments
The following is an example of overloading in a Java program:
package MyFirstPackage;
class SampleClass10 {
void sampleMethod(){
System.out.println("executing sample method");
}
void sampleMethod(float b){
System.out.println("executing sample method" + b);
}
}
class SampleClass20 extends SampleClass10 {
void sampleMethod1(){
System.out.println("executing sample method 2");
}
void sampleMethod1(int a){
System.out.println("executing sample method 2" + a);
}
}
public class OverLoading {
public static void main(String[] args) {
SampleClass20 methodcall = new SampleClass20();
methodcall.sampleMethod1();
methodcall.sampleMethod();
methodcall.sampleMethod1(12);
methodcall.sampleMethod(1);
}
}The output will be as follows:
executing sample method 2 executing sample method executing sample method 212 executing sample method1.0
The subclass accessing the method of a superclass and changing its behavior as per the request of a subclass is called overriding.
The following is an example of overriding in a Java program:
package MyFirstPackage;
class SampleClass100 {
void sampleMethod(){
System.out.println("executing sample method");
}
void sampleMethod(float b){
System.out.println("executing sample method" + b);
}
}
class SampleClass200 extends SampleClass100 {
void sampleMethod(){
System.out.println("overidding is done");
}
void sampleMethod1(int a){
System.out.println("executing sample method 2" + a);
}
}
public class OverRiding {
public static void main(String[] args) {
SampleClass200 methodcall = new SampleClass200();
methodcall.sampleMethod();
}
}The output will be as follows:
overriding is done