Variable-argument method

Var-Argument method:
Method which accepts any number of arguments is called var-argument method.

Syntax:
Access_Specifier Aceess_Modifier Return_Type methodName(DataType1... var1){
       //Method body
}

Rule of Var-Argument method:

• Only one argument should be variable argument
• Last argument should be var argument

Example 1:

package com.java.basics;

public class VarArgumentMethod {
    
    public static void display(String... str){
        System.out.print("Number of arguments is " + str.length + " ");
        for (int i = 0; i < str.length; i++) {
            System.out.print(str[i] + " ");
        }
        System.out.println(" ");
    }
    
    public static void main(String[] args) {
        display();
        display("Hello");
        display("Hello", "World");
        display("Hello", "World", "Java");
    }
}

Output:
Number of arguments is 0
Number of arguments is 1 Hello
Number of arguments is 2 Hello World
Number of arguments is 3 Hello World Java

Example 2:

package com.java.basics;

public class VariableArgumentMethod {
    
    public static int sum(int... va){
        System.out.print("Number of arguments is " + va.length + " and addition result is: ");
        int sum = 0;
        for (int i = 0; i < va.length; i++) {
            sum += va[i];
        }
        return sum;
    }
    
    public static void main(String[] args) {
        System.out.println(sum());
        System.out.println(sum(25));
        System.out.println(sum(15, 25));
        System.out.println(sum(10, 20, 30));
    }
}

Output:
Number of arguments is 0 and addition result is: 0
Number of arguments is 1 and addition result is: 25
Number of arguments is 2 and addition result is: 40
Number of arguments is 3 and addition result is: 60