<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.1" id="WebApp_ID"
	xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
	xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
	<display-name>T269_mvc_student</display-name>
	<servlet>
		<servlet-name>mvc</servlet-name>
		<servlet-class>com.hpw.framework.DispatchServlet</servlet-class>
		<init-param>
			<param-name>configurationLocation</param-name>
			<param-value>/hpw.xml</param-value>
		</init-param>
	</servlet>
	<servlet-mapping>
		<servlet-name>mvc</servlet-name>
		<url-pattern>*.action</url-pattern>
	</servlet-mapping>

</web-app>

②导入jar包

mvc.jar框架包

③BaseDao（通用增删改方法、查询、分页）

package hpw..util;

import java.lang.reflect.Field;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;

import com.hpw.util.DBAccess;
import com.hpw.util.PageBean;

/**
 * 所有Dao层的父类
 * 	BookDao
 * 	UserDao
 * 	OrderDao
 * 	...
 * @author Administrator
 *
 * @param <T>
 */
public class BaseDao<T> {
	/**
	 * 通用的增删改方法
	 * @param book
	 * @throws Exception
	 */
	public void executeUpdate(String sql, T t, String[] attrs) throws Exception {
//		String[] attrs = new String[] {"bid", "bname", "price"};
		Connection con = DBAccess.getConnection();
		PreparedStatement pst = con.prepareStatement(sql);
//		pst.setObject(1, book.getBid());
//		pst.setObject(2, book.getBname());
//		pst.setObject(3, book.getPrice());
		/*
		 * 思路：
		 * 	1.从传进来的t中读取属性值
		 *  2.往预定义对象中设置了值
		 *  
		 *  t->book
		 *  f->bid
		 */
		for (int i = 0; i < attrs.length; i++) {
			Field f = t.getClass().getDeclaredField(attrs[i]);
			f.setAccessible(true);
			pst.setObject(i+1, f.get(t));
		}
		pst.executeUpdate();
	}
	
	/**
	 * 通用分页查询
	 * @param sql
	 * @param clz
	 * @return
	 * @throws Exception
	 */
	public List<T> executeQuery(String sql,Class<T> clz,PageBean pageBean) throws Exception{
		List<T> list = new ArrayList<T>();
		Connection con = DBAccess.getConnection();;
		PreparedStatement pst = null;
		ResultSet rs = null;
		
		/*
		 * 是否需要分页？
		 * 	无需分页（项目中的下拉框，查询条件教员下拉框，无须分页）	
		 * 	必须分页（项目中列表类需求、订单列表、商品列表、学生列表...）
		 */
		if(pageBean != null && pageBean.isPagination()) {
//			必须分页（列表需求）
			String countSQL = getCountSQL(sql);
			pst = con.prepareStatement(countSQL);
			rs = pst.executeQuery();
			if(rs.next()) {
				pageBean.setTotal(String.valueOf(rs.getObject(1)));
			}
			
//			挪动到下面，是因为最后才处理返回的结果集
//			-- sql=SELECT * FROM t_mvc_book WHERE bname like '%圣墟%'
//			-- pageSql=sql limit (page-1)*rows,rows 	对应某一页的数据
//			-- countSql=select count(1) from (sql) t 	符合条件的总记录数
			String pageSQL = getPageSQL(sql,pageBean);//符合条件的某一页数据
			pst = con.prepareStatement(pageSQL);
			rs = pst.executeQuery();
		}else {
//			不分页（select需求）
			pst = con.prepareStatement(sql);//符合条件的所有数据
			rs = pst.executeQuery();
		}
		
		
		while (rs.next()) {
			T t = clz.newInstance();
			Field[] fields = clz.getDeclaredFields();
			for (Field f : fields) {
				f.setAccessible(true);
				f.set(t, rs.getObject(f.getName()));
			}
			list.add(t);
		}
		return list;
	}

	/**
	 * 将原生SQL转换成符合条件的总记录数countSQL
	 * @param sql
	 * @return
	 */
	private String getCountSQL(String sql) {
//		-- countSql=select count(1) from (sql) t 	符合条件的总记录数
		return "select count(1) from ("+sql+") t";
	}

	/**
	 * 将原生SQL转换成pageSQL
	 * @param sql
	 * @param pageBean
	 * @return
	 */
	private String getPageSQL(String sql,PageBean pageBean) {
//		(this.page - 1) * this.rows
//		pageSql=sql limit (page-1)*rows,rows
		return sql + " limit "+ pageBean.getStartIndex() +","+pageBean.getRows();
	}
}

④StudentDao


public class StudentDao extends BaseDao<Student>{

	public void add(Student s)throws Exception{
		String sql = "insert into t_struts_student values(?,?,?,'adad','男','测试')";
		super.executeUpdate(sql, s, new String[] {"sid","cid","sname"});
	}
	
	public void edit(Student s)throws Exception{
		String sql = "update t_struts_student set cid=?,sname=? where sid=?";
		super.executeUpdate(sql, s, new String[] {"cid","sname","sid"});
	}
	
	public void delete(Student s)throws Exception{
		String sql = "delete from t_struts_student where sid=?";
		super.executeUpdate(sql, s, new String[] {"sid"});
	}
	
	public List<Student> list(Student s,PageBean pageBean) throws Exception {
		String sql = "select * from t_struts_student where 1 = 1";
		String sname = s.getSname();
		if(StringUtils.isNotBlank(sname)) {
			sql += " and sname like '%"+sname+"%' ";
		}
		
		return super.executeQuery(sql, Student.class, pageBean);
	}
	
	public Student getOne(Student s)throws Exception{
		String sql = "select * from t_struts_student where sid="+s.getSid();
		return super.executeQuery(sql, Student.class, null).get(0);
	}
	
}

⑤子控制器Action

package com.hpw.web;

import java.util.List;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.hpw.dao.StudentDao;
import com.hpw.entity.Student;
import com.hpw.framework.ActionSupport;
import com.hpw.framework.ModelDriver;
import com.hpw.util.PageBean;

public class StudentAction extends ActionSupport implements ModelDriver<Student>{

	private Student student = new Student();
	
	private StudentDao dao = new StudentDao();

	public Student getModel() {
		return student;
	}

	public String list(HttpServletRequest req,HttpServletResponse resp) throws Exception {
		PageBean pageBean = new PageBean();
		pageBean.setRequest(req);
		List<Student> list = dao.list(student, pageBean);
		req.setAttribute("students", list);
		req.setAttribute("pageBean", pageBean);
		return "list"; 
	}
	
	public String add(HttpServletRequest req,HttpServletResponse resp)throws Exception{
		dao.add(student);
		return "toList";
	}
	
	public String delete(HttpServletRequest req,HttpServletResponse resp)throws Exception{
		dao.delete(student);
		return "toList";
	}
	
	public String edit(HttpServletRequest req,HttpServletResponse resp)throws Exception{
		dao.edit(student);
		return "toList";
	}
	
	public String toEdit(HttpServletRequest req,HttpServletResponse resp)throws Exception{
		if(student.getSid()!=0) {
			Student s = dao.getOne(student);
			req.setAttribute("s", s);
		}
		return "toEdit";
	}
}

⑥ 在src文件夹目录下创建conf文件夹

hpw.xml

<?xml version="1.0" encoding="UTF-8"?>
<config>

<action type="com.hpw.web.StudentAction" path="/student">
	<forward path="/studentList.jsp" redirect="false" name="list"/>
	<forward path="/student.action?methodName=list" redirect="true" name="toList"/>
	<forward path="/studentEdit.jsp" redirect="false" name="toEdit"/>
</action>

</config>

⑦jsp界面

门户界面（主界面）

<%@ page language="java" contentType="text/html; charset=UTF-8"
	pageEncoding="UTF-8"%>
<%@ taglib uri="http://jsp.veryedu.cn" prefix="z"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<link
	href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css"
	rel="stylesheet">
<script
	src="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/js/bootstrap.js"></script>
<title>学生列表</title>
<style type="text/css">
.page-item input {
	padding: 0;
	width: 40px;
	height: 100%;
	text-align: center;
	margin: 0 6px;
}
 
.page-item input, .page-item b {
	line-height: 38px;
	float: left;
	font-weight: 400;
}
 
.page-item.go-input {
	margin: 0 10px;
}
</style>
</head>
<body>
	<form class="form-inline"
		action="${pageContext.request.contextPath }/student.action?methodName=list" method="post">
		<div class="form-group mb-2">
			<input type="text" class="form-control-plaintext" name="sname"
				placeholder="请输入学生名称">
			<!-- <input name="rows" value="20" type="hidden">   一页显示二十行-->
			<!-- <input name="pagination" value="false" type="hidden">   不分页-->
		</div>
		<button type="submit" class="btn btn-primary mb-2">查询</button>
		<a class="btn btn-primary mb-2" href="${pageContext.request.contextPath }/student.action?methodName=toEdit">新增</a>		
	</form>
 
	<table class="table table-striped bg-success">
		<thead>
			<tr>
				<th scope="col">学生id</th>
				<th scope="col">班级编号</th>
				<th scope="col">学生名字</th>
				<th scope="col">操作</th>
			</tr>
		</thead>
		<tbody>
			<c:forEach var="s" items="${students}">
				<tr>
					<td>${s.sid }</td>
					<td>${s.cid }</td>
					<td>${s.sname }</td>
					<td>
					<a href="${pageContext.request.contextPath }/student.action?methodName=toEdit&sid=${s.sid}">修改</a>
					<a href="${pageContext.request.contextPath }/student.action?methodName=delete&sid=${s.sid}">删除</a>
					</td>
				</tr>
			</c:forEach>
		</tbody>
	</table>
	
	<z:page pageBean="${pageBean }"></z:page>
 
</body>
</html>

增加/修改界面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>新增与修改</title>
</head>
<body>

<form class="form-inline"
		action="${pageContext.request.contextPath }/student.action?methodName=${empty s ? 'add' : 'edit'}" method="post">
		学生id：<input type="text" name="sid" value="${s.sid} "><br>
		班级编号：<input type="text" name="cid" value="${s.cid} "><br>
		学生名字：<input type="text" name="sname" value="${s.sname} "><br>
		操作：<input type="submit"><br>
</form>
</body>
</html>