反射reflect

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反射调用方法实体类

测试类

package bean;import java.lang.reflect.Constructor;import java.lang.reflect.Method;import org.junit.Test;/* * 测试类 * public 方法（通过反射去调用共有的方法） * private 方法（通过反射去调用私有的方法） * 共有构造方法（通过反射去调用的构造方法） */public class Reflect {    // public 方法（通过反射去调用共有的方法）    @Test    public void test1() {        SysUser sysUser = new SysUser();        try {            Class<?> clazz = Class.forName("bean.SysUser");            Method method = clazz.getMethod("eat1", String.class);            String invoke = (String) method.invoke(sysUser, "111");            System.out.println("invoke=" + invoke);        } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();        }    }    // private 方法（通过反射去调用私有的方法）    @Test    public void test2() {        SysUser sysUser = new SysUser();        try {            Class<?> clazz = Class.forName("bean.SysUser");            Method method = clazz.getDeclaredMethod("eat2", String.class);            method.setAccessible(true);            String invoke = (String) method.invoke(sysUser, "112");            System.out.println("invoke=" + invoke);        } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();        }    }    // 共有构造方法（通过反射去调用的构造方法）    @Test    public void test3() {        SysUser sysUser = new SysUser();        try {            Class<?> clazz = Class.forName("bean.SysUser");            Constructor<?> constructor = clazz.getConstructor(String.class);            SysUser newInstance = (SysUser) constructor.newInstance("2222");            System.out.println(newInstance.name);        } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();        }    }}

实体类

package bean;/* *  */public class SysUser {    String name;    String password;    public String eat1(String str) {        return str;    }    private String eat2(String str) {        return str;    }    public SysUser(String name) {        this.name = name;    }    public SysUser(String name, String password) {        super();        this.name = name;        this.password = password;    }    public SysUser() {    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public String getPassword() {        return password;    }    public void setPassword(String password) {        this.password = password;    }    @Override    public String toString() {        return "SysUser [name=" + name + ", password=" + password + "]";    }}

CommonServlet

package com.huaxin.webexam.web.common;import java.io.IOException;import java.lang.reflect.Method;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class CommonServlet extends HttpServlet {    protected void doGet(HttpServletRequest request, HttpServletResponse response)            throws ServletException, IOException {        request.setCharacterEncoding("utf-8");        response.setContentType("text/html; charset=UTF-8");        try {            /** 0.当前字节码文件 **/            Class<? extends CommonServlet> clazz = this.getClass();            /** 1.获取method参数 **/            String method = request.getParameter("method");            /** 2.获取method 反射出当前访问的方法 **/            Method method2 = clazz.getMethod(method, HttpServletRequest.class, HttpServletResponse.class);            /** 3.调用方法 **/            // this调用 ，参数有request，response            Object path = method2.invoke(this, request, response);            System.out.println("path " + path);            /** 4.跳转页面 **/            if (path != null) {                request.getRequestDispatcher("/WEB-INF/jsp/" + path.toString() + ".jsp").forward(request, response);            }        } catch (Exception e) {            e.printStackTrace();        }    }    protected void doPost(HttpServletRequest request, HttpServletResponse response)            throws ServletException, IOException {        request.setCharacterEncoding("utf-8");        doGet(request, response);    }}

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