How to select which overloaded version of a method to call without using a cast?

Question

i have a question to Java Overload Methods.

Suppose i have an overload methods foo:

public static String foo(String x) {
    return "foo-String: " + x;
}

public static String foo(Object x) {
    return "foo-Object: " + x;
}

How can I implement to functions like

public static String useString() {
    return(foo("useString"));   
}
public static String useObject() {
    return(foo("useObject"));   
}

of which one uses the overloaded string method, and one the overloaded object method?

The call of the foo-Method should use an String input. (that means i do not want to work with a cast like

return(foo((Object)"useObject")); 

Maybe you can help me with this problem

EDIT:

Above, just is an example for an exercise. I am trying to understand Overloads and Dispatch better and was looking for alternative solution for calling (and selecting) an overload method.

Answer 1

If we keep aside the motive behind this for a second and try to answer the direct question, you can create an object reference instead of using an explicit cast.

public static String useObject() {
    Object obj = "useObject";
    return foo(obj);   
}

While the end result is the same, you avoid the need to have an explicit cast with this approach.

Answer 2

I guess this is a bit of cheating, but strictly speaking this doesn't use a cast on the syntax level:

public static String useObject() {
    return(foo(Object.class.cast("useObject")));   
}

Answer 3

If you want to use the method that receive an Object, you can upcast your string to object:

public class Main {
    public static String foo(String x) {
        return "foo-String: " + x;
    }

    public static String foo(Object x) {
        return "foo-Object: " + x;
    }

    public static String useString() {
        return(foo("useString"));
    }
    public static String useObject() {
        Object x = "useObject";
        return(foo(x));
    }

    public static void main(String[] args) {
        System.out.println(Main.useObject());
    }
}

The method public static String foo(Object x) will be called