编译器根据什么标准选择重载方法之一

Question

What is the formal reason of prefering one to method to the other(by compiler)? Why it chooses first one for bytes etc. I know that int can represent bytes, but float also. Why is it so formally?

public class MethodCurrier {

    public void setValue(int wrt){//naglowek
        System.out.println("Typ int "+ wrt);
    }
    public void setValue(float wrt){//naglowek
        System.out.println("Typ float "+ wrt);
    }
    public static void main(String[] args) {
        MethodCurrier currier = new MethodCurrier();
        currier.setValue(4);//int
        currier.setValue(2.3f);//float
        currier.setValue('c');//char
        currier.setValue((byte)4);

    }
}

Answer 1

The Java Language Specification defines this as follows:

If more than one member method is both accessible and applicable to a method invocation, it is necessary to choose one to provide the descriptor for the run-time method dispatch. The Java programming language uses the rule that the most specific method is chosen.

The informal intuition is that one method is more specific than another if any invocation handled by the first method could be passed on to the other one without a compile-time type error.

In your case, the int method is more specific than the float method, because an int can be implictly converted to a float , but not vice versa.

Answer 2

因为Java语言规范是这样说的。