Method Overloading in java

METHOD OVERLOADING

  •  In a class defining multiple method with a same name and different parameter is
    known as method overloading.
  •  Parameter should differ either in terms of parameter type or
    parameter length.
  •  In a class we can overload both static and non-static method.
  • The overloaded method is invoked based on the argument.
  •  Any two method having same name should not be match of in terms of argument.
  •  Method overloading is used to achieve compile time polymorphism.

When to use method overloading:


  •  When developing application if we come across an operation which has required the different  parameter then we go for method overloading
  • i.e. while doing payment in Amazon website we have many payment option like debit  card, credit card and   wallet option to make payment but operation is same.

Method overloading Example


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class Demo1
{
 
  	void test()
 
	{
 
		System.out.println("running no arg test method");
	}
 
	void test(int arg)
	{
 
		System.out.println("running int arg test method");
 
	}
 
	static void test(double arg1)//static method
	{
 
		System.out.println("running double arg static test method");
	}
 
 
}
 
 
public class MethodOverloading
{
	public static void main(String[] args) {
 
		System.out.println("*************************");
 
		Demo1 obj1=new Demo1();
 
		obj1.test();//calling no arg test method
 
		obj1.test(10);// calling int arg test method
 
		System.out.println("*************************");
 
		Demo1.test(12.4);//calling static test double arg method
 
 
		System.out.println("**************************");
 
	}
}
 
 
output:
 
*************************
running no arg test method
running int arg test method
*************************
running double arg static test method
**************************

Var arg method

Example of Var Arg Method
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package MethodOverloading;
 
public class Varmethod
{
   void add(int...args)
   {
     int sum=0;
     for(int i=0;i<args.length;i++)
      {
        sum=sum+args[i];
      }
 
     System.out.println(sum);
   }
 
    void add(int a)
     {
       System.out.println("runnning int arg");
     }
     void add(int a,int b)
     {
       System.out.println("multi arg method");
     }
     public static void main(String[] args)
      {
         Varmethod v=new Varmethod();
          v.add(5);// int arg method called
          v.add(5,7);//two int arg method called
          v.add(2,2,3,4);// var arg method called
   }
}
 
OUTPUT:
runnning int arg
multi arg method
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