... <看更多>

Overload is decided at compile-time, so when the first method gets the abc parameter it sees it as an Object (not a String ) and calls ... ... <看更多>

import java.util.Scanner;. interface Operator {. int calc(int a, int b);. } class Add implements Operator {. public int calc(int a, int b) { return a + b; }. }. ... <看更多>