如何反映像java.Math这样的类（我想提取参数的函数类型，如：Math.abs（）等）

Question

I am trying to get the parameters' types(double, int) of the functions like Math.sin(double), Math.abs(int)

Answer 1

You can use getParameterTypes() for publicly declared methods. Something like this:

import java.lang.reflect.Method;

public class Main {

public static void main(String[] args) {
    for (Method m : Math.class.getMethods()) {
        Class<?>[] params = m.getParameterTypes();
        for (Class<?> param : params) {
            System.out.println(m.getName()+":"+param.getCanonicalName());
        }
     }
   } 
}

Answer 2

You can't chage the type of that function bec that are provided by Java and it's final class you can't chage the type