Overloaded method selection based on the parameter's real type

Question

I\'m experimenting with this code:

interface Callee {
    public void foo(Object o);
    public void foo(String s);
    public void foo(Integer i);
}

class          


        

Answer 1

If there is an exact match between the number and types of arguments specified in the method call and the method signature of an overloaded method then that is the method that will be invoked. You are using Object references, so java decides at compile time that for Object param, there is a method which accepts directly Object. So it called that method 3 times.