java反射实现根据类名和方法名字符串调用

import java.lang.reflect.Method;

public class Test {
 public static void main(String[] args) throws  Exception {
  String className = "com.runqianapp.ngr.alias.example.FunClass";
  String methodName = "sayHello";
  Class clz = Class.forName(className);
  //  
  Object obj = clz.newInstance();
  //获取方法  
  Method m = obj.getClass().getDeclaredMethod(methodName, String.class);
  //调用方法  
  String  result = (String) m.invoke(obj, "aaaaa");
  System.out.println(result);
 }
}

class FunClass{
 public String sayHello(String s){
  System.out.println(s);
  return "hello!";
 }
}