Question

Alright so I just want to confirm something.

I am creating a wrapper class for java’s Properties class and I came a cross a little question.

if I have

public static void set(String key, Object value) { _p.set(key, value.toString()); }

and

public static void set(String key, SomeClass value) { _p.set(key, value.SomeMethod().toString()); }

is the Object overload called only when none of the other overloads suffice?

Answer 1

Java will choose the most specific match, in your case a boolean will be automatically converted using auto-boxing boolean <-> Boolean. If you use any other type like String the Object variant will be used.

The Details you find in the Java Language
Specification
see 8.4.9 Overloading

Added in response to comment:

You can easily test the behaviour with some code like:

class A {
    public void print(Object o) {
        System.out.println("A.print " + o);
    }

    public static void main(String[] args) {
        B b = new B();
        A a = new A();
        b.print("test b");
        a.print("test a");
        ((A) b).print("test a or b");
    }
}

class B extends A {
    public void print(Object o) {
        System.out.println("B.print " + o);
    }
}

Prints:

B.print test b
A.print test a
B.print test a or b

I hope now it is more clear what happens.