Java 实例 使用方法重载执行算术运算

public class JavaExample
{
    int add(int num1, int num2)
    {
        return num1+num2;
    }
    int add(int num1, int num2, int num3)
    {
        return num1+num2+num3;
    }
    int add(int num1, int num2, int num3, int num4)
    {
        return num1+num2+num3+num4;
    }
    public static void main(String[] args) 
    {    
        JavaExample obj = new JavaExample();
        //This will call the first add method
        System.out.println("Sum of two numbers: "+obj.add(10, 20));
        //This will call second add method
        System.out.println("Sum of three numbers: "+obj.add(10, 20, 30));
        //This will call third add method
        System.out.println("Sum of four numbers: "+obj.add(1,  2, 3, 4));
    }
}

Sum of two numbers: 30
Sum of three numbers: 60
Sum of four numbers: 10