java框架008——MVC模式

桃扇骨 2023-10-06 19:39 4阅读 0赞

## 一、Java Web 开发流程 ##

![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_20_color_FFFFFF_t_70_g_se_x_16]

## 二、MVC的概念 ##

。MVC是Model-View-Controller的简称，即模型-视图-控制器。  
。MVC是一种设计模式，它把应用程序分成三个核心模块：模型、视图、控制器，它们各自处理自己的任务。

> 1、模型(Model)  
> 模型是应用程序的主体部分，`模型表示业务数据和业务逻辑`。  
> 一个模型能为多个视图提供数据。  
> 由于应用于模型的代码只需写一次就可以被多个视图重用，所以提高了代码的可重用性。  
> 2、视图(View)  
> 视图是`用户看到并与之交互的界面`，作用如下：  
> ——视图向用户显示相关的数据。  
> ——接受用户的输入。  
> ——不进行任何实际的业务处理。  
> 3、控制器(Controller)  
> 控制器`接受用户的输入并调用模型和视图去完成用户的需求`。  
> 控制器接收请求并决定调用哪个模型组件去处理请求，然后决定调用哪个视图来显示模型处理返回的数据。

![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_20_color_FFFFFF_t_70_g_se_x_16 1]

## 三、MVC模式的实现例子 ##

项目结构  
![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_12_color_FFFFFF_t_70_g_se_x_16]  
![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_13_color_FFFFFF_t_70_g_se_x_16]  
使用的数据库表  
![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_20_color_FFFFFF_t_70_g_se_x_16 2]

## c3p0-config.xml ##

<?xml version="1.0" encoding="UTF-8"?>
    
    <c3p0-config>
      <named-config name="com.dgut.javaweb"> 
      	
    	<property name="driverClass">com.mysql.cj.jdbc.Driver</property>
    	<property name="jdbcUrl">jdbc:mysql://localhost:3306/jdbc?serverTimezone=Hongkong</property>
    	<property name="user">root</property>
    	<property name="password">75688</property>
    	
        <property name="acquireIncrement">2</property>
        <property name="initialPoolSize">2</property>
        <property name="minPoolSize">2</property>
        <property name="maxPoolSize">10</property>
      </named-config>
    </c3p0-config>

## web.xml ##

<?xml version="1.0" encoding="UTF-8"?>
    <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xmlns="http://xmlns.jcp.org/xml/ns/javaee" 
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" id="WebApp_ID" version="4.0">
      <display-name>javawebMVC</display-name>
     
      
      <servlet>
    	  	<servlet-name>initServlet</servlet-name>
    	  	<servlet-class>com.dgut.mvc.controller.InitServlet</servlet-class>
    	  	<load-on-startup>1</load-on-startup>
      </servlet>
      
     
      <filter>
    	  	<filter-name>encodingFilter</filter-name>
    	  	<filter-class>com.dgut.mvc.filter.EncodingFilter</filter-class>
      </filter>
      
      <filter-mapping>
    	  	<filter-name>encodingFilter</filter-name>
    	  	<url-pattern>/*</url-pattern>
    	  	
    	  	<dispatcher>REQUEST</dispatcher>
    	  	<dispatcher>FORWARD</dispatcher>
      </filter-mapping>
    </web-app>

## JdbcTools ##

### JdbcTools.java ###

package com.dgut.mvc.utils;
    
    import java.sql.Connection;
    import java.sql.ResultSet;
    import java.sql.Statement;
    
    import com.mchange.v2.c3p0.ComboPooledDataSource;
    
    public class JdbcTools {
        
    
    	private static ComboPooledDataSource cpds = null;
    
    	public static Connection getConnectionFromPool() throws Exception {
        
    		if (cpds == null)
    			cpds = new ComboPooledDataSource("com.dgut.javaweb");
    		return cpds.getConnection();
    	}
    
    	public static Connection getConnection() throws Exception {
        
    //		String driverClass = "com.mysql.cj.jdbc.Driver";
    //		String jdcbUrl = "jdbc:mysql://localhost:3306/jdbc?serverTimezone=Hongkong";
    //		String user = "root";
    //		String password = "75688";
    //		Class.forName(driverClass);
    //
    //		Connection connection = DriverManager.getConnection(jdcbUrl, user, password);
    		return getConnectionFromPool();
    	}
    
    	public static void releaseResource(Statement statement, Connection connection) {
        
    		try {
        
    			if (statement != null)
    				statement.close();
    		} catch (Exception e1) {
        
    			e1.printStackTrace();
    		}
    		try {
        
    			if (connection != null)
    				connection.close();
    		} catch (Exception e2) {
        
    			e2.printStackTrace();
    		}
    	}
    
    	public static void releaseResource(ResultSet rs, Statement statement, Connection connection) {
        
    		try {
        
    			if (rs != null)
    				rs.close();
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		}
    		try {
        
    			if (statement != null)
    				statement.close();
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		}
    		try {
        
    			if (connection != null)
    				connection.close();
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		}
    	}
    
    }

## Bean ##

### Member.java ###

![在这里插入图片描述][a78f2a1ef5274ddca40b50dfacb05ea3.png]

### MemberSearchCondition.java ###

![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_18_color_FFFFFF_t_70_g_se_x_16]

## Dao ##

### DAO.java ###

package com.dgut.mvc.dao;
    
    import java.sql.Connection;
    import java.sql.SQLException;
    import java.util.List;
    
    public interface DAO<T> {
        
    
    	// 查询一个
    	public T fetch(Connection connection, String sql, Object... objects) throws SQLException;
    
    	// 查询一组
    	public List<T> fetchList(Connection connection, String sql, Object... objects) throws SQLException;
    
    	// 增删改
    	public void update(Connection connection, String sql, Object... objects) throws SQLException;
    
    	// 查询一个分量
    	public <E> E fetchScaler(Connection connection, String sql, Object... objects) throws SQLException;
    
    }

### MemberDao.java ###

package com.dgut.mvc.dao;
    
    import java.sql.Connection;
    import java.sql.SQLException;
    import java.util.List;
    
    import com.dgut.mvc.bean.Member;
    import com.dgut.mvc.bean.MemberSearchCondition;
    
    public interface MemberDao {
        
    
    	public void addMember(Connection connection, Member member) throws SQLException;
    
    	public void deleteMember(Connection connection, int id) throws SQLException;
    
    	public void updateMember(Connection connection, Member member) throws SQLException;
    
    	public Member searchMemberById(Connection connection, int id) throws SQLException;
    
    	public List<Member> fetchAllMembers(Connection connection) throws SQLException;
    
    	public List<Member> searchMemberByCondition(Connection connection, MemberSearchCondition conditions)
    			throws SQLException;
    }

## DAOImpl ##

### DAOJdbcImpl.java ###

package com.dgut.mvc.daoImpl;
    
    import java.lang.reflect.ParameterizedType;
    import java.lang.reflect.Type;
    import java.sql.Connection;
    import java.sql.SQLException;
    import java.util.List;
    
    import org.apache.commons.dbutils.QueryRunner;
    import org.apache.commons.dbutils.handlers.BeanHandler;
    import org.apache.commons.dbutils.handlers.BeanListHandler;
    import org.apache.commons.dbutils.handlers.ScalarHandler;
    
    import com.dgut.mvc.dao.DAO;
    
    public class DAOJdbcImpl<T> implements DAO<T> {
        
    	private QueryRunner queryRunner;
    	private Class<T> type;
    
    	@SuppressWarnings("unchecked")
    	public DAOJdbcImpl() {
        
    		queryRunner = new QueryRunner();
    		type = getSuperClassGenricType(getClass(), 0);
    	}
    
    	@SuppressWarnings("rawtypes")
    	private Class getSuperClassGenricType(Class clazz, int index) {
        
    		Type genType = clazz.getGenericSuperclass();
    		if (!(genType instanceof ParameterizedType)) {
        
    			return Object.class;
    		}
    		Type[] params = ((ParameterizedType) genType).getActualTypeArguments();
    		if (index >= params.length || index < 0) {
        
    			return Object.class;
    		}
    		if (!(params[index] instanceof Class)) {
        
    			return Object.class;
    		}
    		return (Class) params[index];
    	}
    
    	public T fetch(Connection connection, String sql, Object... objects) throws SQLException {
        
    		BeanHandler<T> rsh = new BeanHandler<T>(type);
    		return queryRunner.query(connection, sql, rsh, objects);
    	}
    
    	public List<T> fetchList(Connection connection, String sql, Object... objects) throws SQLException {
        
    		BeanListHandler<T> rsh = new BeanListHandler<T>(type);
    		return queryRunner.query(connection, sql, rsh, objects);
    	}
    
    	public void update(Connection connection, String sql, Object... objects) throws SQLException {
        
    		queryRunner.update(connection, sql, objects);
    	}
    
    	public <E> E fetchScaler(Connection connection, String sql, Object... objects) throws SQLException {
        
    		ScalarHandler<E> rsh = new ScalarHandler<E>();
    		return (E) queryRunner.query(connection, sql, rsh, objects);
    	}
    
    }

### MemberDaoJdbcImpl.java ###

package com.dgut.mvc.daoImpl;
    
    import java.sql.Connection;
    import java.sql.SQLException;
    import java.util.List;
    
    import com.dgut.mvc.bean.Member;
    import com.dgut.mvc.bean.MemberSearchCondition;
    import com.dgut.mvc.dao.MemberDao;
    
    public class MemberDaoJdbcImpl extends DAOJdbcImpl<Member> implements MemberDao {
        
    
    	public void addMember(Connection connection, Member member) throws SQLException {
        
    		String sql = "INSERT INTO member (name,Idcard, phone, credits) VALUES (?, ?, ?, ?)";
    		Object[] objs = {
         member.getName(), member.getIdCard(), member.getPhone(), member.getCredits() };
    		update(connection, sql, objs);
    	}
    
    	public void deleteMember(Connection connection, int id) throws SQLException {
        
    		String sql = "DELETE FROM member WHERE memberId=?";
    		update(connection, sql, id);
    	}
    
    	public void updateMember(Connection connection, Member member) throws SQLException {
        
    		String sql = "UPDATE member set name=?, idCard=?, phone=?, credits=? WHERE memberId=?";
    		Object[] objs = {
         member.getName(), member.getIdCard(), member.getPhone(), member.getCredits(),
    				member.getId() };
    		update(connection, sql, objs);
    	}
    
    	public Member searchMemberById(Connection connection, int id) throws SQLException {
        
    		String sql = "SELECT memberId id,name,idCard,phone,credits FROM member WHERE memberId=?";
    		return fetch(connection, sql, id);
    	}
    
    	public List<Member> fetchAllMembers(Connection connection) throws SQLException {
        
    		String sql = "SELECT memberId id,name,idCard,phone,credits FROM member";
    		return fetchList(connection, sql);
    	}
    
    	@Override
    	public List<Member> searchMemberByCondition(Connection connection, MemberSearchCondition conditions)
    			throws SQLException {
        
    		String sql = "SELECT memberId id,name,idCard,phone,credits FROM member "
    				+ "WHERE name like ? AND idCard like ? AND phone like ? ";
    		Object[] objs = {
         conditions.getName(), conditions.getIdCard(), conditions.getPhone() };
    		return fetchList(connection, sql, objs);
    	}
    
    }

## TestDao ##

### TestMemberDao.java ###

package com.dgut.mvc.test;
    
    import java.sql.Connection;
    import java.util.List;
    
    import org.junit.jupiter.api.Test;
    
    import com.dgut.mvc.bean.Member;
    import com.dgut.mvc.dao.MemberDao;
    import com.dgut.mvc.daoImpl.MemberDaoJdbcImpl;
    import com.dgut.mvc.utils.JdbcTools;
    
    class TestMemberDao {
        
    
    	@Test
    	public void testGetAll() {
        
    		MemberDao dao = new MemberDaoJdbcImpl();
    		Connection connection = null;
    		try {
        
    			connection = JdbcTools.getConnection();
    			List<Member> members = dao.fetchAllMembers(connection);
    			System.out.println(members);
    
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    	}
    
    	@Test
    	public void testGetById() {
        
    		int id = 10;
    		MemberDao dao = new MemberDaoJdbcImpl();
    		Connection connection = null;
    		try {
        
    			connection = JdbcTools.getConnection();
    			Member member = dao.searchMemberById(connection, id);
    			System.out.println(member);
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    
    	}
    
    	@Test
    	public void testUpdateMember() {
        
    		Member member = new Member(7, "heihei", "20201001", "13920201001", 200);
    		MemberDao dao = new MemberDaoJdbcImpl();
    		Connection connection = null;
    		try {
        
    			connection = JdbcTools.getConnection();
    			dao.updateMember(connection, member);
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    	}
    
    	@Test
    	public void testDeleteMember() {
        
    		int id = 13;
    		MemberDao dao = new MemberDaoJdbcImpl();
    		Connection connection = null;
    		try {
        
    			connection = JdbcTools.getConnection();
    			dao.deleteMember(connection, id);
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    	}
    
    	@Test
    	public void testAddMember() {
        
    		Member member = new Member(null, "CCC", "2020002", "1392020002", 100);
    		MemberDao dao = new MemberDaoJdbcImpl();
    		Connection connection = null;
    		try {
        
    			connection = JdbcTools.getConnection();
    			dao.addMember(connection, member);
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    	}
    }

## Servlet ##

### InitServlet.java ###

package com.dgut.mvc.controller;
    
    import java.io.IOException;
    import java.sql.Connection;
    
    import javax.servlet.Servlet;
    import javax.servlet.ServletConfig;
    import javax.servlet.ServletException;
    import javax.servlet.ServletRequest;
    import javax.servlet.ServletResponse;
    
    import com.dgut.mvc.utils.JdbcTools;
    
    public class InitServlet implements Servlet {
        
    
    	@Override
    	public void destroy() {
        
    	}
    
    	@Override
    	public ServletConfig getServletConfig() {
        
    		return null;
    	}
    
    	@Override
    	public String getServletInfo() {
        
    		return null;
    	}
    
    	@Override
    	public void init(ServletConfig arg0) throws ServletException {
        
    		Connection connection = null;
    		try {
        
    			connection = JdbcTools.getConnection();
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    	}
    
    	@Override
    	public void service(ServletRequest arg0, ServletResponse arg1) throws ServletException, IOException {
        
    
    	}
    
    }

### MemberServlet.java ###

package com.dgut.mvc.controller;
    
    import java.io.IOException;
    import java.lang.reflect.InvocationTargetException;
    import java.lang.reflect.Method;
    import java.util.List;
    
    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 com.dgut.mvc.bean.Member;
    import com.dgut.mvc.bean.MemberSearchCondition;
    import com.dgut.mvc.service.MemberService;
    
    @WebServlet("*.do") // 响应所有以.do结尾的请求
    public class MemberServlet extends HttpServlet {
        
    	private static final long serialVersionUID = 1L;
    	private MemberService memberService;
    
    	public MemberServlet() {
        
    		super();
    		this.memberService = new MemberService();
    	}
    
    	protected void doGet(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
        
    		String servletpath = request.getServletPath();// 获取请求路径
    		String methodName = servletpath.substring(1, servletpath.length() - 3);// 提取路径中“.do”前的名字
    		System.out.println("servletpath==" + servletpath);
    		System.out.println("methodName==" + methodName);
    
    		// 使用反射机制,即通过上面取得的方法名，自动去调用下面具体的方法，
    		// 例如请求为listMember.do的路径，将调用listMember（）方法
    		try {
        
    			Method method = getClass().getDeclaredMethod(methodName, HttpServletRequest.class,
    					HttpServletResponse.class);
    			method.invoke(this, request, response);// 调用Method类代表的方法。可以实现动态调用，例如可以动态的传人参数，可以把方法参数化。
    		} catch (NoSuchMethodException | IllegalAccessException | IllegalArgumentException
    				| InvocationTargetException e) {
        
    			e.printStackTrace();
    		}
    	}
    
    	// 查询所有
    	public void listMember(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
        
    		List<Member> members = memberService.getAllMembers();
    
    		request.setAttribute("members", members);
    		request.getRequestDispatcher("/WEB-INF/views/memberList.jsp").forward(request, response);
    	}
    
    	// 删除
    	public void deleteMember(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
        
    		int id = Integer.parseInt(request.getParameter("id"));
    		memberService.deleteMembers(id);
    		// 回到listMember页面,显示所有信息
    		listMember(request, response);
    
    	}
    
    	// 转到添加页面
    	public void toInputMember(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
        
    		request.getRequestDispatcher("/WEB-INF/views/inputMember.jsp").forward(request, response);
    	}
    
    	// 添加
    	public void inputMember(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
        
    		String name = request.getParameter("name");
    		String idCard = request.getParameter("idCard");
    		String phone = request.getParameter("phone");
    		int credits = Integer.parseInt(request.getParameter("credits"));
    
    		Member member = new Member(null, name, idCard, phone, credits);
    
    		boolean res = memberService.inputMembers(member);
    
    		if (res) {
        
    			request.setAttribute("SucceedMessage", "添加成功");
    			request.getRequestDispatcher("/WEB-INF/views/succeed.jsp").forward(request, response);
    		} else {
        
    			request.setAttribute("ErrorMessage", "添加失败，IdCard已存在");
    			request.getRequestDispatcher("/WEB-INF/views/inputMember.jsp").forward(request, response);
    		}
    	}
    
    	// 转到编辑页面
    	public void editMember(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
        
    		int id = Integer.parseInt(request.getParameter("id"));
    
    		Member member = memberService.getMembers(id);
    
    		request.setAttribute("member", member);
    
    		request.getRequestDispatcher("/WEB-INF/views/updateMember.jsp").forward(request, response);
    
    	}
    
    	// 编辑
    	public void updateMember(HttpServletRequest request, HttpServletResponse response) throws Exception, IOException {
        
    		int id = Integer.parseInt(request.getParameter("id"));
    		String name = request.getParameter("name");
    		String idCard = request.getParameter("idCard");
    		String phone = request.getParameter("phone");
    		int credits = Integer.parseInt(request.getParameter("credits"));
    
    		Member member = new Member(id, name, idCard, phone, credits);
    
    		memberService.updateMember(member);
    
    		request.setAttribute("SucceedMessage", "编辑成功");
    		request.getRequestDispatcher("/WEB-INF/views/succeed.jsp").forward(request, response);
    
    	}
    
    	// 模糊查询
    	public void searchMember(HttpServletRequest request, HttpServletResponse response) throws Exception, IOException {
        
    		String name = request.getParameter("name");
    		String idCard = request.getParameter("idCard");
    		String phone = request.getParameter("phone");
    
    		MemberSearchCondition sc = new MemberSearchCondition(name, idCard, phone);
    
    		List<Member> members = memberService.searchMemberByCondition(sc);
    
    		request.setAttribute("members", members);
    		request.getRequestDispatcher("/WEB-INF/views/memberList.jsp").forward(request, response);
    
    	}
    
    	protected void doPost(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
        
    		doGet(request, response);
    	}
    
    }

## Service ##

### MemberService.java ###

package com.dgut.mvc.service;
    
    import java.sql.Connection;
    import java.util.ArrayList;
    import java.util.List;
    
    import com.dgut.mvc.bean.Member;
    import com.dgut.mvc.bean.MemberSearchCondition;
    import com.dgut.mvc.dao.MemberDao;
    import com.dgut.mvc.daoImpl.MemberDaoJdbcImpl;
    import com.dgut.mvc.utils.JdbcTools;
    
    public class MemberService {
        
    	private MemberDao dao;
    
    	public MemberService() {
        
    		this.dao = new MemberDaoJdbcImpl();
    	}
    
    	// 获取所有
    	public List<Member> getAllMembers() {
        
    		Connection connection = null;
    		List<Member> memberms = new ArrayList<Member>();
    		try {
        
    			connection = JdbcTools.getConnection();
    			memberms = dao.fetchAllMembers(connection);
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    		return memberms;
    	}
    
    	// 删除
    	public void deleteMembers(int id) {
        
    		Connection connection = null;
    
    		try {
        
    			connection = JdbcTools.getConnection();
    			dao.deleteMember(connection, id);
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    	}
    
    	// 添加
    	public boolean inputMembers(Member member) {
        
    		boolean result = false;
    		Connection connection = null;
    		try {
        
    			connection = JdbcTools.getConnection();
    			dao.addMember(connection, member);
    			result = true;// 添加成功，则为true
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    		return result;
    	}
    
    	// 查找
    	public Member getMembers(int id) {
        
    		Connection connection = null;
    		Member member = new Member();
    		try {
        
    			connection = JdbcTools.getConnection();
    			member = dao.searchMemberById(connection, id);
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    		return member;
    	}
    
    	// 编辑
    	public void updateMember(Member member) {
        
    		Connection connection = null;
    		try {
        
    			connection = JdbcTools.getConnection();
    			dao.updateMember(connection, member);
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    	}
    
    	// 模糊查询
    	public List<Member> searchMemberByCondition(MemberSearchCondition conditions) {
        
    		Connection connection = null;
    		List<Member> memberms = new ArrayList<Member>();
    		try {
        
    			connection = JdbcTools.getConnection();
    			memberms = dao.searchMemberByCondition(connection, conditions);
    		} catch (Exception e) {
        
    			e.printStackTrace();
    		} finally {
        
    			JdbcTools.releaseResource(null, connection);
    		}
    		return memberms;
    	}
    
    }

### EncodingFilter.java ###

package com.dgut.mvc.filter;
    
    import java.io.IOException;
    
    import javax.servlet.Filter;
    import javax.servlet.FilterChain;
    import javax.servlet.ServletException;
    import javax.servlet.ServletRequest;
    import javax.servlet.ServletResponse;
    
    public class EncodingFilter implements Filter {
        
    
    	@Override
    	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
    			throws IOException, ServletException {
        
    		request.setCharacterEncoding("utf-8");
    		chain.doFilter(request, response);
    	}
    
    }

## view ##

### index.jsp ###

### memberList.jsp ###

<%@page import="com.dgut.mvc.bean.Member"%>
    <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
    <%@page import="java.util.List,java.util.ArrayList"%>
    <%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html>
    <html>
    <head>
    <meta charset="UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    	<h3>显示所有界面</h3>
    	<hr>
    		<form action="${pageContext.request.contextPath }/searchMember.do" method="post">
    			Name:<input type="text"  name="name" value="${param.name }"><br>
    			IdCard:<input type="text"  name="idCard" value="${param.idCard }"><br>
    			Phone:<input type="text"  name="phone" value="${param.phone }"><br>
    			<input type="submit" value="模糊查询">
    		</form>
    	<hr>
    	<%
    		List<Member> members = (List<Member>) request.getAttribute("members");
    	%>
    	<a href="${pageContext.request.contextPath }/toInputMember.do">Add Member</a>
    	<table border="1" cellspacing="0" cellpadding="5">
    		<tr>
    			<th>Name</th>
    			<th>IdCard</th>
    			<th>Phone</th>
    			<th>Credits</th>
    			<th>update</th>
    			<th>delete</th>
    		</tr>
    		<%
    		if(members!=null){
    			for(Member member:members){
    		%>
    		
    		<tr>
    			<td><%=member.getName() %></td>
    			<td><%=member.getIdCard() %></td>
    			<td><%=member.getPhone() %></td>
    			<td><%=member.getCredits() %></td>
    			<td><a href="${pageContext.request.contextPath }/editMember.do?id=<%=member.getId() %>">Update</a></td>
    			<td><a href="${pageContext.request.contextPath }/deleteMember.do?id=<%=member.getId() %>">Delete</a></td>
    		</tr>
    		<%
    			}
    			
    		}
    		 %>
    	</table>
    	
    	<h1>use jstl</h1>
    	<table border="1" cellspacing="0" cellpadding="5">
    		<tr>
    			<th>Name</th>
    			<th>IdCard</th>
    			<th>Phone</th>
    			<th>Credits</th>
    			<th>update</th>
    			<th>delete</th>
    		</tr>
    		<c:if test="${!empty requestScope.members}">
    			<c:forEach items="${requestScope.members}" var="member">
    				<tr>
    					<td>${member.name}</td> 
    					<td>${member.idCard}</td> 
    					<td>${member.phone}</td>
    					<td>${member.credits}</td>
    					<td><a href="${pageContext.request.contextPath }/editMember.do?id=${member.id }">Update</a></td>
    					<td><a href="${pageContext.request.contextPath }/deleteMember.do?id=${member.id}">Delete</a></td>
    				</tr>
    			</c:forEach>
    		</c:if>
    	</table>
    </body>
    </html>

### succeed.jsp ###

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html>
    <html>
    <head>
    <meta charset="UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    	<h4>${requestScope.SucceedMessage }</h4>
    	<a href="${pageContext.request.contextPath }/listMember.do">Member Manager</a>
    </body>
    </html>

### inputMember.jsp ###

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html>
    <html>
    <head>
    <meta charset="UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    
    	<h3>添加界面</h3>
    	<h4>${requestScope.ErrorMessage }</h4>
    
    
    	
    	
    	<form action="${pageContext.request.contextPath }/inputMember.do" method="post">
    		Name:<input type="text" name="name" value="${param.name}"><br>
    		IdCard:<input type="text" name="idCard" value="${param.idCard}"><br>
    		Phone:<input type="text" name="phone" value="${param.phone}"><br>
    		Credits:<input type="text" name="credits" value="${param.credits}"><br>
    		<input type="submit" value="添加">
    		<a href="${pageContext.request.contextPath }/listMember.do">Member Manager</a>
    	</form>
    </body>
    </html>

### updateMember.jsp ###

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html>
    <html>
    <head>
    <meta charset="UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    
    	<h3>编辑界面</h3>
    	<h4>${requestScope.ErrorMessage }</h4>
    
    	
    	
    	<form action="${pageContext.request.contextPath }/updateMember.do" method="post">
    		<input type="hidden"  name="idCard" value="${requestScope.member.idCard}"><br>
    		<input type="hidden"  name="id" value="${requestScope.member.id}"><br>
    		
    		Name:<input type="text" name="name" value="${requestScope.member.name}"><br>
    		IdCard:<input type="text" disabled="disabled" name="idCard" value="${requestScope.member.idCard}"><br>
    		Phone:<input type="text" name="phone" value="${requestScope.member.phone}"><br>
    		Credits:<input type="text" name="credits" value="${requestScope.member.credits}"><br>
    		<input type="submit" value="确定编辑">
    		<a href="${pageContext.request.contextPath }/listMember.do">Member Manager</a>
    	</form>
    </body>
    </html>

![在这里插入图片描述][d10b9bc502484c7b8291c9c323ce7bbf.png]  
![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_18_color_FFFFFF_t_70_g_se_x_16 1]  
![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_16_color_FFFFFF_t_70_g_se_x_16]  
![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_17_color_FFFFFF_t_70_g_se_x_16]

[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_20_color_FFFFFF_t_70_g_se_x_16]: https://img-blog.csdnimg.cn/565d623691af4fbb949df0e64832d0ae.png?x-oss-process=image/watermark,type_ZHJvaWRzYW5zZmFsbGJhY2s,shadow_50,text_Q1NETiBA5rGf5bee55uK5b2k,size_20,color_FFFFFF,t_70,g_se,x_16
[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_20_color_FFFFFF_t_70_g_se_x_16 1]: https://img-blog.csdnimg.cn/1e64be855a3f4f60a105b12a649633d9.png?x-oss-process=image/watermark,type_ZHJvaWRzYW5zZmFsbGJhY2s,shadow_50,text_Q1NETiBA5rGf5bee55uK5b2k,size_20,color_FFFFFF,t_70,g_se,x_16
[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_12_color_FFFFFF_t_70_g_se_x_16]: https://img-blog.csdnimg.cn/7c71f06d9abb4605acc568d6ac4e9df8.png?x-oss-process=image/watermark,type_ZHJvaWRzYW5zZmFsbGJhY2s,shadow_50,text_Q1NETiBA5rGf5bee55uK5b2k,size_12,color_FFFFFF,t_70,g_se,x_16
[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_13_color_FFFFFF_t_70_g_se_x_16]: https://img-blog.csdnimg.cn/96aa3067a2fb460e8565ec153232aa84.png?x-oss-process=image/watermark,type_ZHJvaWRzYW5zZmFsbGJhY2s,shadow_50,text_Q1NETiBA5rGf5bee55uK5b2k,size_13,color_FFFFFF,t_70,g_se,x_16
[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_20_color_FFFFFF_t_70_g_se_x_16 2]: https://img-blog.csdnimg.cn/16432c57494440f0b3b937fe8b625ba6.png?x-oss-process=image/watermark,type_ZHJvaWRzYW5zZmFsbGJhY2s,shadow_50,text_Q1NETiBA5rGf5bee55uK5b2k,size_20,color_FFFFFF,t_70,g_se,x_16
[a78f2a1ef5274ddca40b50dfacb05ea3.png]: https://img-blog.csdnimg.cn/a78f2a1ef5274ddca40b50dfacb05ea3.png
[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_18_color_FFFFFF_t_70_g_se_x_16]: https://img-blog.csdnimg.cn/9d0f5cbf691d4077be9f49566a9ebb00.png?x-oss-process=image/watermark,type_ZHJvaWRzYW5zZmFsbGJhY2s,shadow_50,text_Q1NETiBA5rGf5bee55uK5b2k,size_18,color_FFFFFF,t_70,g_se,x_16
[d10b9bc502484c7b8291c9c323ce7bbf.png]: https://img-blog.csdnimg.cn/d10b9bc502484c7b8291c9c323ce7bbf.png
[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_18_color_FFFFFF_t_70_g_se_x_16 1]: https://img-blog.csdnimg.cn/d6cbafc659614d939270a0c4cc47be54.png?x-oss-process=image/watermark,type_ZHJvaWRzYW5zZmFsbGJhY2s,shadow_50,text_Q1NETiBA5rGf5bee55uK5b2k,size_18,color_FFFFFF,t_70,g_se,x_16
[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_16_color_FFFFFF_t_70_g_se_x_16]: https://img-blog.csdnimg.cn/a77fae12719c4c0f8c32badbf4d2345d.png?x-oss-process=image/watermark,type_ZHJvaWRzYW5zZmFsbGJhY2s,shadow_50,text_Q1NETiBA5rGf5bee55uK5b2k,size_16,color_FFFFFF,t_70,g_se,x_16
[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBA5rGf5bee55uK5b2k_size_17_color_FFFFFF_t_70_g_se_x_16]: https://img-blog.csdnimg.cn/e2fd9b919d314f2a9eff003c0d166c35.png?x-oss-process=image/watermark,type_ZHJvaWRzYW5zZmFsbGJhY2s,shadow_50,text_Q1NETiBA5rGf5bee55uK5b2k,size_17,color_FFFFFF,t_70,g_se,x_16