java,方法重载小问题

//显示/int result =sum(a:10,b:20);报错
import java.util.*;

public class HelloWorld {
public static void main(String[] args) {
//System.out.println("Hello world!");
int result =sum(a:10,b:20);
System.out.println(result);
}
public static int sum(int a,int b){
return a+b;
}
public static double sum(double a, double b){
return a+b;
}
public static int sum(int a,int b,int c){
return a+b+c;
}

}

你这是什么神仙写法？？？？？？？？不需要a:和b:

public class HelloWorld {
    public static void main(String[] args) {
        //System.out.println("Hello world!");
        int result = sum(10, 20);
        System.out.println(result);
    }

    public static int sum(int a, int b) {
        return a + b;
    }

    public static double sum(double a, double b) {
        return a + b;
    }

    public static int sum(int a, int b, int c) {
        return a + b + c;
    }

}