具备的测试工具:Eclipse,MySQL数据库,HBuilder,jstl1.2jar,mysql.connector.java.8.0.jar
jstl1.2jar下载地址:https://pan.baidu.com/s/1T23zxoEg3jlZHFikrbWtHw
mysql.connector.java.8.0.jar包下载地址:https://pan.baidu.com/s/1kqfOuxo3nOT--CTrlp1BmA
首先打开Eclipse创建一个动态Web项目(Dynamic Web Project),在Src下分别创建以下包
其中web其实就是对应action层,这就是典型的MVC模型,这是属于后端
首先创建与你数据库的表结构对应的实体类
1、我的数据库结构如下
建立数据库
create database LoveDB;
建立数据表LoveInHeart
use LoveDB;
create table LoveInHeart(
lid int auto_increment primary key,
lname varchar(50) not null,
lsex varchar(50) not null,
ltime date not null,
lmoney float
);
然后可以向里面添加一些测试数据
insert into LoveInHeart(lname,lsex,ltime,lmoney)
values ('张三','男','1999-02-15',1000000);insert into LoveInHeart(lname,lsex,ltime,lmoney)
values ('李四','女','1998-8-19',1000);insert into LoveInHeart(lname,lsex,ltime,lmoney)
values ('科比','男','2008-05-05',100);
然后实体类的属性参数要和数据库的表结构保持一致,注:实体类是放在entity包下
声明变量以后进行封装,右键选择 source --> Getter and Setter ,然后select All 点击完成
接下来创建与数据库链接的DatabaseConnection类来完成与数据库的交互,在dao包下新建一个类,名字为:BaseDB
package com.nf.dao;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class BaseDao {
private static final String DRIVER_CLASS = "com.mysql.cj.jdbc.Driver";
private static final String SERVER_IP = "localhost";// 服务器IP地址
private static final String DATABASE_NAME = "lovedb";// 连接到哪一个数据库
private static final String USER_NAME = "root";// 用户名
private static final String PASSWORD = "123456";// 密码
public Connection getConnection() {
Connection conn = null;
String jdbcUrl = "jdbc:mysql://" + SERVER_IP + ":3306/" + DATABASE_NAME
+ "?serverTimezone=Asia/Shanghai&useSSL=true";
try {
Class.forName(DRIVER_CLASS);
conn = DriverManager.getConnection(jdbcUrl, USER_NAME, PASSWORD);
} catch (Exception e) {
System.out.println("获取连接时,异常" + e.getMessage());
conn = null;
}
return conn;
}
public void closeAll(Connection conn, PreparedStatement pst, ResultSet rs) {
try {
if (rs != null) {
rs.close();
}
if (pst != null) {
pst.close();
}
if (conn != null) {
conn.close();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
在dao层下面创建一个Interface类,声明三个方法(查询、添加、删除),名字:LoveInHeartDao
package com.nf.dao;
import java.util.List;
import com.nf.entity.LoveInHeart;
import com.nf.util.MyPage;
public interface LoveInHeartDao{
public List<LoveInHeart> getAll(MyPage myPage);
public boolean add(LoveInHeart love);
public boolean delete(int id);
}
然后创建一个实现接口class类(Implments),名字:LoveInHeart_Impl
package com.nf.dao;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import com.nf.entity.LoveInHeart;
import com.nf.util.MyPage;
public class LoveInHeartDaoImpl extends BaseDao implements LoveInHeartDao {
@Override //查询
public List<LoveInHeart> getAll(MyPage myPage) {
// 操作数据库,需要一个连接Connection
Connection connection = getConnection();
PreparedStatement prepareStatement = null;
ResultSet resultSet = null;
List<LoveInHeart> loveInHeartList = new ArrayList();
String sql_data = "select * from loveinheart order by lid desc ";
String sql_recodeCount = "select count(1) as mycount from loveinheart";
sql_data += "limit ";
sql_data += (myPage.getCurrentPage()-1)*myPage.getPerPageSize();
sql_data += ",";
sql_data += myPage.getPerPageSize();
System.out.println("分页的SQL:"+sql_data);
try {
prepareStatement = connection.prepareStatement(sql_data);
resultSet = prepareStatement.executeQuery();
while (resultSet.next()) {
LoveInHeart l = new LoveInHeart();
l.setLid(resultSet.getInt("lid"));
l.setLname(resultSet.getString("lname"));
l.setLsex(resultSet.getString("lsex"));
l.setLtime(resultSet.getDate("ltime"));
l.setLmoney(resultSet.getFloat("lmoney"));
loveInHeartList.add(l);
}
} catch (SQLException e) {
e.printStackTrace();
}
try {
prepareStatement = connection.prepareStatement(sql_recodeCount);
resultSet = prepareStatement.executeQuery();
resultSet.next();
myPage.setRecodeCount( resultSet.getInt("mycount") );
} catch (SQLException e) {
e.printStackTrace();
}
closeAll(connection, prepareStatement, resultSet);
// System.out.println(connection);
return loveInHeartList;
}
@Override //添加
public boolean add(LoveInHeart love) {
// 操作数据库,需要一个连接Connection
Connection connection = getConnection();
PreparedStatement prepareStatement = null;
try {
prepareStatement = connection
.prepareStatement("insert into LoveInHeart(lname,lsex,ltime,lmoney) values (?,?,?,?)");
prepareStatement.setString(1, love.getLname());
prepareStatement.setString(2, love.getLsex());
prepareStatement.setDate(3, love.getLtime());
prepareStatement.setFloat(4, love.getLmoney());
prepareStatement.executeUpdate();
closeAll(connection, prepareStatement, null);
return true;
} catch (SQLException e) {
e.printStackTrace();
return false;
}
}
@Override //删除
public boolean delete(int id) {
// 操作数据库,需要一个连接Connection
Connection connection = getConnection();
PreparedStatement prepareStatement = null;
try {
prepareStatement = connection
.prepareStatement("delete from LoveInHeart where lid=?");
prepareStatement.setInt(1, id);
prepareStatement.executeUpdate();
closeAll(connection, prepareStatement, null);
return true;
} catch (SQLException e) {
e.printStackTrace();
return false;
}
}
}
接下来在Service层再创建一个interface类,名字:LoveInHeartService
package com.nf.service;
import java.util.List;
import com.nf.entity.LoveInHeart;
import com.nf.entity.MyData;
public interface LoveInHeartService {
public MyData getAll(int currentPage);
public boolean add(LoveInHeart love);
public boolean delete(int id);
}
随机在同Service层下实现该接口,实现类名:LoveInHeartServiceImpl,在这里实现类的方式直接调用dao层的方法就可以了
package com.nf.service;
import java.util.List;
import com.nf.dao.LoveInHeartDao;
import com.nf.dao.LoveInHeartDaoImpl;
import com.nf.entity.LoveInHeart;
import com.nf.entity.MyData;
import com.nf.util.MyPage;
public class LoveInHeartServiceImpl implements LoveInHeartService {
private LoveInHeartDao loveDao = new LoveInHeartDaoImpl();
@Override
public MyData getAll(int currentPage) {
MyPage myPage = new MyPage();
myPage.setCurrentPage(currentPage);
//myPage.setRecodeCount( 0 );//让Dao层来计算
myPage.setPerPageSize( 10 );//设置每页10条
List<LoveInHeart> loveList = loveDao.getAll( myPage );
MyData myData = new MyData();
myData.setLoveInHeartList(loveList);
myData.setMyPage(myPage);
return myData;
}
@Override
public boolean add(LoveInHeart love) {
return loveDao.add(love);
}
@Override
public boolean delete(int id) {
// TODO Auto-generated method stub
return loveDao.delete(id);
}
}
接下来就是存放Servlet的action层,Servlet名:LoveInHeartActionGetAll(获取全部信息的Servlet)
package com.nf.web;
import java.io.IOException;
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.nf.entity.LoveInHeart;
import com.nf.entity.MyData;
import com.nf.service.LoveInHeartService;
import com.nf.service.LoveInHeartServiceImpl;
@WebServlet("/LoveInHeartActionGetAll")
public class LoveInHeartActionGetAll extends HttpServlet {
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//第一步:先获得客户端的参数
String currentPage_str = request.getParameter("currentPage");
if (currentPage_str==null){
currentPage_str = "1";
}
int currentPage = Integer.parseInt(currentPage_str);
//第二步:调用Model(service层)的方法,来获取数据
LoveInHeartService loveService = new LoveInHeartServiceImpl();
MyData myData = loveService.getAll(currentPage);
//第三步:把数据存放到request的属性中,然后把请求转发到jsp
request.setAttribute("myData", myData);
request.getRequestDispatcher("showList.jsp").forward(request, response);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
}
再在同一层下创建添加的Servlet,Servlet名:LoveInHeartActionAdd
package com.nf.web;
import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
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.nf.entity.LoveInHeart;
import com.nf.service.LoveInHeartService;
import com.nf.service.LoveInHeartServiceImpl;
@WebServlet("/LoveInHeartActionAdd")
public class LoveInHeartActionAdd extends HttpServlet {
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//获取参数
//?lname=123&lsex=男<ime=111&lmoney=222
String lname = request.getParameter("lname");
String lsex = request.getParameter("lsex");
String ltime = request.getParameter("ltime");
String lmoney = request.getParameter("lmoney");
//把参数构造成一个实体类
LoveInHeart love = new LoveInHeart();
love.setLname(lname);
love.setLsex(lsex);
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
try {
love.setLtime( new java.sql.Date( sdf.parse(ltime).getTime() ) );
} catch (ParseException e) {
System.out.println("日期格式转换错误");
e.printStackTrace();
}
love.setLmoney( Float.parseFloat(lmoney) );
//调用Model,保存数据
LoveInHeartService loveService = new LoveInHeartServiceImpl();
boolean flag = loveService.add(love);
//跳转
if (flag){
//response.sendRedirect("showList.jsp");
response.sendRedirect("LoveInHeartActionGetAll");
}else{
response.sendRedirect("error.jsp");
}
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
}
删除的Servlet,Servlet名:LoveInHeartActionDelete
package com.nf.web;
import java.io.IOException;
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.nf.service.LoveInHeartService;
import com.nf.service.LoveInHeartServiceImpl;
@WebServlet("/LoveInHeartActionDelete")
public class LoveInHeartActionDelete extends HttpServlet {
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//获取参数
String id_str = request.getParameter("id");
int id = Integer.parseInt(id_str);
//调用model的api
LoveInHeartService loveService = new LoveInHeartServiceImpl();
boolean flag = loveService.delete(id);
if (flag){
response.sendRedirect("LoveInHeartActionGetAll");
}else{
response.sendRedirect("error.jsp");
}
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
}
添加JSP代码,此网页只有主体,无其它程序文件之类的引用,JSP名:add.jsp
<form action="LoveInHeartActionAdd">
<table border="1" width="80%" align="center">
<tr>
<td colspan="2" align="center">中华慈善捐款等级</td>
</tr>
<tr>
<td width="180px">姓名:</td>
<td><input type="text" name="lname"></td>
</tr>
<tr>
<td width="180px">性别:</td>
<td>
<input type="radio" name="lsex" value="男" checked="checked">男</input>
<input type="radio" name="lsex" value="女">女</input>
</td>
</tr>
<tr>
<td width="180px">捐款日期:</td>
<td><input type="text" name="ltime">(yyyy年MM月dd日)</td>
</tr>
<tr>
<td width="180px">捐款金额:</td>
<td><input type="text" name="lmoney">(元)</td>
</tr>
<tr>
<td colspan="2" align="center">
<input type="submit" value="提交">
<input type="reset" value="重置">
</td>
</tr>
</table>
</form>
首页的全部代码,这里只是用来做一个中转站,并不实现什么功能,所以可以只保留这一点东西,JSP名:index.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%><%
response.sendRedirect("LoveInHeartActionGetAll");
%>
最重要的展示信息界面,包括了删除功能,JSP名:showList.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ 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">
<title>展示所有信息</title>
</head>
<script type="text/javascript">
function mydelete(id){
alert(id);
//ajax();
}
</script>
<body>
总纪录条数:${myData.myPage.recodeCount},
每页大小:${myData.myPage.perPageSize },
一共${myData.myPage.pageCount}页
<br><br>
<c:forEach begin="${myData.myPage.pageBegin}" end="${myData.myPage.pageEnd}" varStatus="sta">
<a href="LoveInHeartActionGetAll?currentPage=${sta.index}">第${sta.index}页</a>
</c:forEach>
<table align="center" border="1" >
<tr>
<td colspan="6" align="right">
---中华爱心捐款查询系统<a href="add.jsp">添加新捐款</a></span>
</td>
</tr>
<tr>
<td>编号</td>
<td>姓名</td>
<td>性别</td>
<td>捐款金额</td>
<td>捐款时间</td>
<td>操作</td>
</tr>
<c:forEach items="${myData.loveInHeartList}" var="love">
<tr>
<td>${love.lid}</td>
<td>${love.lname}</td>
<td>${love.lsex}</td>
<td>${love.lmoney}</td>
<td>${love.ltime}</td>
<td>
<a href="LoveInHeartActionDelete?id=${love.lid}">删除</a>
<a href="javascript:mydelete(${love.lid})">无刷新删除1</a>
<button onclick="mydelete(${love.lid})">无刷新删除2</button>
</td>
</tr>
</c:forEach>
</table>
<c:forEach begin="${myData.myPage.pageBegin}" end="${myData.myPage.pageEnd}" varStatus="sta">
<a href="LoveInHeartActionGetAll?currentPage=${sta.index}">第${sta.index}页</a>
</c:forEach>
</body>
</html>
最终结果图如下: