java暴力反射

暴力反射可以获取java类中私有的方法

儿子

package cn.itcast.travel.web.servlet;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebServlet("/user/*")
public class UserServlet extends BaseServlet {
    protected void add(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        System.out.println("userServlet add方法");

    }

    protected void find(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        System.out.println("userServlet find方法");
    }
}

老爹

package cn.itcast.travel.web.servlet;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

public class BaseServlet extends HttpServlet {
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//        完成方法分发
//                获取请求路径
            String uri =  req.getRequestURI();// /travel/user/123

//                获取方法名称
      String methodname =  uri.substring(uri.lastIndexOf("/")+1);
        System.out.println(methodname);
//                获取方法对象 反射相关的知识
        try {
//            getDeclaredMethod忽略访问权限修饰符
            Method method = this.getClass().getDeclaredMethod(methodname,HttpServletRequest.class,HttpServletResponse.class);
        //执行方发
//                暴力反射
            method.setAccessible(true);
            method.invoke(this,req,resp);
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }
    }
}