Java--小项目（登录、增删改查、分页、搜索）
Java--小项目（登录、增删改查、分页、搜索）
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概念
技术选型
Servlet、JSP、MySQL、JDBCTempleat、Duird、BeanUtilS、tomcat
功能介绍
登录功能，列表展示，数据添加，数据编辑，数据删除，批量删除，分页展示，关键字搜索
创建JavaWeb项目
导入依赖
添加页面文件
数据库
create database little; -- 创建数据库
use little; -- 使用数据库
create table user( -- 创建表
id int primary key auto_increment,
name varchar(20) not null,
gender varchar(5),
age int,
address varchar(32),
qq varchar(20),
email varchar(50,
username varchar(32),
password varchar(32),
);
列表展示
思路
首先我们需要一组列表的数据，那么我们就需要一个相对应servlet，通过我们的三层架构，使用service同一做接口，然后调用dao层使用JBDC操作数据库，这样我们可以获得一个map集合的数据，然后就是渲染数据到jsp页面了，通过JSTL和EL把数据循环渲染到表里面，达到列表的展示
list.jsp
<%--
Created by IntelliJ IDEA.
User: tanglei
Date: 2020/6/28
Time: 下午2:15
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<!-- 网页使用的语言 -->
<html lang="zh-CN">
<head>
<!-- 指定字符集 -->
<meta charset="utf-8">
<!-- 使用Edge最新的浏览器的渲染方式 -->
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<!-- viewport视口：网页可以根据设置的宽度自动进行适配，在浏览器的内部虚拟一个容器，容器的宽度与设备的宽度相同。
width: 默认宽度与设备的宽度相同
initial-scale: 初始的缩放比，为1:1 -->
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- 上述3个meta标签*必须*放在最前面，任何其他内容都*必须*跟随其后！ -->
<title>用户信息管理系统</title>
<!-- 1. 导入CSS的全局样式 -->
<link href="css/bootstrap.min.css" rel="stylesheet">
<!-- 2. jQuery导入，建议使用1.9以上的版本 -->
<script src="js/jquery-2.1.0.min.js"></script>
<!-- 3. 导入bootstrap的js文件 -->
<script src="js/bootstrap.min.js"></script>
<style type="text/css">
td, th {
text-align: center;
}
</style>
</head>
<body>
<div class="container">
<h3 style="text-align: center">用户信息列表</h3>
<table border="1" class="table table-bordered table-hover">
<tr class="success">
<th>编号</th>
<th>姓名</th>
<th>性别</th>
<th>年龄</th>
<th>籍贯</th>
<th>QQ</th>
<th>邮箱</th>
<th>操作</th>
</tr>
<c:forEach items="${users}" var="user" varStatus="s">
<tr>
<td>${s.count}</td>
<td>${user.name}</td>
<td>${user.gender}</td>
<td>${user.age}</td>
<td>${user.address}</td>
<td>${user.qq}</td>
<td>${user.email}</td>
<td><a class="btn btn-default btn-sm" href="update.html">修改</a> <a class="btn btn-default btn-sm"
href="">删除</a></td>
</tr>
</c:forEach>
<tr>
<td colspan="8" align="center"><a class="btn btn-primary" href="add.html">添加联系人</a></td>
</tr>
</table>
</div>
</body>
</html>
servlet
代码文件很多，就不一一展示了
UserListServlet
package cn.guizimo.little.web.servlet;
import cn.guizimo.little.domain.User;
import cn.guizimo.little.service.UserService;
import cn.guizimo.little.service.impl.UserServiceImpl;
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.util.List;
@WebServlet("/userListServlet")
public class UserListServlet extends HttpServlet {
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//调用UserService完成查询
UserService userService = new UserServiceImpl();
List<User> users = userService.findAll();
//存入request域
req.setAttribute("users",users);
//转发到list.jsp
req.getRequestDispatcher("/list.jsp").forward(req,resp);
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
}
测试
登录
思路
登录功能首先就是对表单提交的数据进行比对，验证码可以在生成的时候就把它存入到session中，然后在servlet中进行比对，其他的字段在通过调用dao层的JDBC操作数据库进行比对，最后把登录成功的用户信息存入session中
login.jsp
<%--
Created by IntelliJ IDEA.
User: tanglei
Date: 2020/6/28
Time: 下午7:37
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="utf-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=edge"/>
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<title>管理员登录</title>
<!-- 1. 导入CSS的全局样式 -->
<link href="css/bootstrap.min.css" rel="stylesheet">
<!-- 2. jQuery导入，建议使用1.9以上的版本 -->
<script src="js/jquery-2.1.0.min.js"></script>
<!-- 3. 导入bootstrap的js文件 -->
<script src="js/bootstrap.min.js"></script>
<script type="text/javascript">
function refreshCode() {
let vcode = document.getElementById("vcode");
vcode.src = "${pageContext.request.contextPath}/checkCodeServlet?=" + new Date().getTime();
}
</script>
</head>
<body>
<div class="container" style="width: 400px;">
<h3 style="text-align: center;">管理员登录</h3>
<form action="${pageContext.request.contextPath}/loginServlet" method="post">
<div class="form-group">
<label for="user">用户名：</label>
<input type="text" name="username" class="form-control" id="user" placeholder="请输入用户名"/>
</div>
<div class="form-group">
<label for="password">密码：</label>
<input type="password" name="password" class="form-control" id="password" placeholder="请输入密码"/>
</div>
<div class="form-inline">
<label for="vcode">验证码：</label>
<input type="text" name="verifycode" class="form-control" id="verifycode" placeholder="请输入验证码"
style="width: 120px;"/>
<a href="javascript:refreshCode()"><img src="${pageContext.request.contextPath}/checkCodeServlet"
title="看不清点击刷新" id="vcode"/></a>
</div>
<hr/>
<div class="form-group" style="text-align: center;">
<input class="btn btn btn-primary" type="submit" value="登录">
</div>
</form>
<!-- 出错显示的信息框 -->
<div class="alert alert-warning alert-dismissible" role="alert">
<button type="button" class="close" data-dismiss="alert">
<span>×</span></button>
<strong>${login_msg}</strong>
</div>
</div>
</body>
</html>
LoginServlet
package cn.guizimo.little.web.servlet;
import cn.guizimo.little.domain.User;
import cn.guizimo.little.service.UserService;
import cn.guizimo.little.service.impl.UserServiceImpl;
import org.apache.commons.beanutils.BeanUtils;
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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.util.Map;
@WebServlet("/loginServlet")
public class LoginServlet extends HttpServlet {
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//设置编码
req.setCharacterEncoding("utf-8");
//传递过来的验证码
String verifycode = req.getParameter("verifycode");
HttpSession session = req.getSession();
//session里面的验证码
String checkcode_server = (String) session.getAttribute("CHECKCODE_SERVER");
session.removeAttribute("CHECKCODE_SERVER");
//比对验证码
if (!checkcode_server.equalsIgnoreCase(verifycode)) {
req.setAttribute("login_msg", "验证码错误");
req.getRequestDispatcher("/login.jsp").forward(req, resp);
return;
}
Map<String, String[]> parameterMap = req.getParameterMap();
User user = new User();
try {
BeanUtils.populate(user, parameterMap);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
UserService userService = new UserServiceImpl();
User loginUser = userService.login(user);
if(loginUser != null){
session.setAttribute("user",loginUser);
resp.sendRedirect(req.getContextPath()+"/index.jsp");
}else {
req.setAttribute("login_msg", "登录失败");
req.getRequestDispatcher("/login.jsp").forward(req, resp);
}
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
}
CheckCodeServlet
package cn.guizimo.little.web.servlet;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* 验证码
*/
@WebServlet("/checkCodeServlet")
public class CheckCodeServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {
//服务器通知浏览器不要缓存
response.setHeader("pragma","no-cache");
response.setHeader("cache-control","no-cache");
response.setHeader("expires","0");
//在内存中创建一个长80，宽30的图片，默认黑色背景
//参数一：长
//参数二：宽
//参数三：颜色
int width = 80;
int height = 30;
BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
//获取画笔
Graphics g = image.getGraphics();
//设置画笔颜色为灰色
g.setColor(Color.GRAY);
//填充图片
g.fillRect(0,0, width,height);
//产生4个随机验证码，12Ey
String checkCode = getCheckCode();
//将验证码放入HttpSession中
request.getSession().setAttribute("CHECKCODE_SERVER",checkCode);
//设置画笔颜色为黄色
g.setColor(Color.YELLOW);
//设置字体的小大
g.setFont(new Font("黑体",Font.BOLD,24));
//向图片上写入验证码
g.drawString(checkCode,15,25);
//将内存中的图片输出到浏览器
//参数一：图片对象
//参数二：图片的格式，如PNG,JPG,GIF
//参数三：图片输出到哪里去
ImageIO.write(image,"PNG",response.getOutputStream());
}
/**
* 产生4位随机字符串
*/
private String getCheckCode() {
String base = "0123456789ABCDEFGabcdefg";
int size = base.length();
Random r = new Random();
StringBuffer sb = new StringBuffer();
for(int i=1;i<=4;i++){
//产生0到size-1的随机值
int index = r.nextInt(size);
//在base字符串中获取下标为index的字符
char c = base.charAt(index);
//将c放入到StringBuffer中去
sb.append(c);
}
return sb.toString();
}
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doGet(request,response);
}
}
测试
添加人员
思路
添加操作就是把jsp提交的表单的数据向数据库里面存储，过程为jsp->servlet->service->dao
add.jsp
<%--
Created by IntelliJ IDEA.
User: tanglei
Date: 2020/6/28
Time: 下午8:55
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<!-- HTML5文档-->
<!DOCTYPE html>
<!-- 网页使用的语言 -->
<html lang="zh-CN">
<head>
<!-- 指定字符集 -->
<meta charset="utf-8">
<!-- 使用Edge最新的浏览器的渲染方式 -->
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<!-- viewport视口：网页可以根据设置的宽度自动进行适配，在浏览器的内部虚拟一个容器，容器的宽度与设备的宽度相同。
width: 默认宽度与设备的宽度相同
initial-scale: 初始的缩放比，为1:1 -->
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- 上述3个meta标签*必须*放在最前面，任何其他内容都*必须*跟随其后！ -->
<title>添加用户</title>
<!-- 1. 导入CSS的全局样式 -->
<link href="css/bootstrap.min.css" rel="stylesheet">
<!-- 2. jQuery导入，建议使用1.9以上的版本 -->
<script src="js/jquery-2.1.0.min.js"></script>
<!-- 3. 导入bootstrap的js文件 -->
<script src="js/bootstrap.min.js"></script>
</head>
<body>
<div class="container">
<center><h3>添加联系人页面</h3></center>
<form action="${pageContext.request.contextPath}/addUserServlet" method="post">
<div class="form-group">
<label for="name">姓名：</label>
<input type="text" class="form-control" id="name" name="name" placeholder="请输入姓名">
</div>
<div class="form-group">
<label>性别：</label>
<input type="radio" name="gender" value="男" checked="checked"/>男
<input type="radio" name="gender" value="女"/>女
</div>
<div class="form-group">
<label for="age">年龄：</label>
<input type="text" class="form-control" id="age" name="age" placeholder="请输入年龄">
</div>
<div class="form-group">
<label for="address">籍贯：</label>
<select name="address" class="form-control" id="jiguan">
<option value="广东">广东</option>
<option value="广西">广西</option>
<option value="湖南">湖南</option>
</select>
</div>
<div class="form-group">
<label for="qq">QQ：</label>
<input type="text" class="form-control" name="qq" placeholder="请输入QQ号码"/>
</div>
<div class="form-group">
<label for="email">Email：</label>
<input type="text" class="form-control" name="email" placeholder="请输入邮箱地址"/>
</div>
<div class="form-group" style="text-align: center">
<input class="btn btn-primary" type="submit" value="提交" />
<input class="btn btn-default" type="reset" value="重置" />
<input class="btn btn-default" type="button" value="返回" />
</div>
</form>
</div>
</body>
</html>
AddUserServlet
package cn.guizimo.little.web.servlet;
import cn.guizimo.little.domain.User;
import cn.guizimo.little.service.UserService;
import cn.guizimo.little.service.impl.UserServiceImpl;
import org.apache.commons.beanutils.BeanUtils;
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.util.Map;
@WebServlet("/addUserServlet")
public class AddUserServlet extends HttpServlet {
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
Map<String, String[]> parameterMap = req.getParameterMap();
User user = new User();
try {
BeanUtils.populate(user,parameterMap);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
UserService userService = new UserServiceImpl();
userService.addUser(user);
resp.sendRedirect(req.getContextPath()+"/userListServlet");
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
}
测试
修改
思路
首先我们需要在打开jsp页面的时候就查询到这样的一条记录，通过这一条记录的id作为表单的隐藏域，在servlet里面将数据进行保存即可
update.jsp
<%--
Created by IntelliJ IDEA.
User: tanglei
Date: 2020/6/29
Time: 上午10:44
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<!-- 网页使用的语言 -->
<html lang="zh-CN">
<head>
<!-- 指定字符集 -->
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>修改用户</title>
<link href="css/bootstrap.min.css" rel="stylesheet">
<script src="js/jquery-2.1.0.min.js"></script>
<script src="js/bootstrap.min.js"></script>
</head>
<body>
<div class="container" style="width: 400px;">
<h3 style="text-align: center;">修改联系人</h3>
<form action="${pageContext.request.contextPath}/updateUserServlet" method="post">
<!-- 隐藏域 提交id-->
<input type="hidden" name="id" value="${user.id}">
<div class="form-group">
<label for="name">姓名：</label>
<input type="text" class="form-control" id="name" name="name" value="${user.name}" readonly="readonly" placeholder="请输入姓名" />
</div>
<div class="form-group">
<label>性别：</label>
<c:if test="${user.gender == '男'}">
<input type="radio" name="gender" value="男" checked />男
<input type="radio" name="gender" value="女" />女
</c:if>
<c:if test="${user.gender == '女'}">
<input type="radio" name="gender" value="男" />男
<input type="radio" name="gender" value="女" checked />女
</c:if>
</div>
<div class="form-group">
<label for="age">年龄：</label>
<input type="text" class="form-control" value="${user.age}" id="age" name="age" placeholder="请输入年龄" />
</div>
<div class="form-group">
<label for="address">籍贯：</label>
<select name="address" id="address" class="form-control" >
<c:if test="${user.address == '陕西'}">
<option value="陕西" selected>陕西</option>
<option value="北京">北京</option>
<option value="上海">上海</option>
</c:if>
<c:if test="${user.address == '北京'}">
<option value="陕西" >陕西</option>
<option value="北京" selected>北京</option>
<option value="上海">上海</option>
</c:if>
<c:if test="${user.address == '上海'}">
<option value="陕西" >陕西</option>
<option value="北京">北京</option>
<option value="上海" selected>上海</option>
</c:if>
</select>
</div>
<div class="form-group">
<label for="qq">QQ：</label>
<input type="text" id="qq" class="form-control" value="${user.qq}" name="qq" placeholder="请输入QQ号码"/>
</div>
<div class="form-group">
<label for="email">Email：</label>
<input type="text" id="email" class="form-control" value="${user.email}" name="email" placeholder="请输入邮箱地址"/>
</div>
<div class="form-group" style="text-align: center">
<input class="btn btn-primary" type="submit" value="提交" />
<input class="btn btn-default" type="reset" value="重置" />
<a class="btn btn-default" href="${pageContext.request.contextPath}/userListServlet">返回</a>
</div>
</form>
</div>
</body>
</html>
FindUserServlet
package cn.guizimo.little.web.servlet;
import cn.guizimo.little.domain.User;
import cn.guizimo.little.service.UserService;
import cn.guizimo.little.service.impl.UserServiceImpl;
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;
@WebServlet("/findUserServlet")
public class FindUserServlet extends HttpServlet {
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//1.获取id
String id = req.getParameter("id");
//2.调用Service查询
UserService service = new UserServiceImpl();
User user = service.findUserById(id);
//3.将user存入request
req.setAttribute("user",user);
//4.转发到update.jsp
req.getRequestDispatcher("/update.jsp").forward(req,resp);
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
}
UpdateUserServlet
package cn.guizimo.little.web.servlet;
import cn.guizimo.little.domain.User;
import cn.guizimo.little.service.UserService;
import cn.guizimo.little.service.impl.UserServiceImpl;
import org.apache.commons.beanutils.BeanUtils;
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.util.Map;
@WebServlet("/updateUserServlet")
public class UpdateUserServlet extends HttpServlet {
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//1.设置编码
req.setCharacterEncoding("utf-8");
//2.获取map
Map<String, String[]> map = req.getParameterMap();
//3.封装对象
User user = new User();
try {
BeanUtils.populate(user,map);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
//4.调用Service修改
UserService service = new UserServiceImpl();
service.updateUser(user);
//5.跳转到查询所有Servlet
resp.sendRedirect(req.getContextPath()+"/userListServlet");
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
}
测试
删除
思路
通过获取到对应的id即可到servlet中处理，操作数据库删除，在进行删除的时候可出现提示框
DelUserServlet
package cn.guizimo.little.web.servlet;
import cn.guizimo.little.service.UserService;
import cn.guizimo.little.service.impl.UserServiceImpl;
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;
@WebServlet("/delUserServlet")
public class DelUserServlet extends HttpServlet {
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//1.获取id
String id = req.getParameter("id");
//2.调用service删除
UserService service = new UserServiceImpl();
service.deleteUser(id);
//3.跳转到查询所有Servlet
resp.sendRedirect(req.getContextPath()+"/userListServlet");
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
}
测试
删除选择的多个
思路
和删除差不多，最主要是获取id的集合
DelSelectedServlet
package cn.guizimo.little.web.servlet;
import cn.guizimo.little.service.UserService;
import cn.guizimo.little.service.impl.UserServiceImpl;
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;
@WebServlet("/delSelectedServlet")
public class DelSelectedServlet extends HttpServlet {
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//1.获取所有id
String[] ids = req.getParameterValues("uid");
//2.调用service删除
UserService service = new UserServiceImpl();
service.delSelectedUser(ids);
//3.跳转查询所有Servlet
resp.sendRedirect(req.getContextPath()+"/userListServlet");
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
this.doPost(req, resp);
}
}
测试
分页
思路
在jsp中获取查询的总条数，每页显示的条数，当前的页码，将之传递给服务器，操作数据库进行查询
list.jsp
<%--
Created by IntelliJ IDEA.
User: tanglei
Date: 2020/6/28
Time: 下午2:15
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<!-- 网页使用的语言 -->
<html lang="zh-CN">
<head>
<!-- 指定字符集 -->
<meta charset="utf-8">
<!-- 使用Edge最新的浏览器的渲染方式 -->
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<!-- viewport视口：网页可以根据设置的宽度自动进行适配，在浏览器的内部虚拟一个容器，容器的宽度与设备的宽度相同。
width: 默认宽度与设备的宽度相同
initial-scale: 初始的缩放比，为1:1 -->
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- 上述3个meta标签*必须*放在最前面，任何其他内容都*必须*跟随其后！ -->
<title>用户信息管理系统</title>
<!-- 1. 导入CSS的全局样式 -->
<link href="css/bootstrap.min.css" rel="stylesheet">
<!-- 2. jQuery导入，建议使用1.9以上的版本 -->
<script src="js/jquery-2.1.0.min.js"></script>
<!-- 3. 导入bootstrap的js文件 -->
<script src="js/bootstrap.min.js"></script>
<style type="text/css">
td, th {
text-align: center;
}
</style>
<script>
function deleteUser(id) {
//用户安全提示
if (confirm("您确定要删除吗？")) {
//访问路径
location.href = "${pageContext.request.contextPath}/delUserServlet?id=" + id;
}
}
window.onload = function () {
//给删除选中按钮添加单击事件
document.getElementById("delSelected").onclick = function () {
if (confirm("您确定要删除选中条目吗？")) {
var flag = false;
//判断是否有选中条目
var cbs = document.getElementsByName("uid");
for (var i = 0; i < cbs.length; i++) {
if (cbs[i].checked) {
//有一个条目选中了
flag = true;
break;
}
}
if (flag) {//有条目被选中
//表单提交
document.getElementById("form").submit();
}
}
}
//1.获取第一个cb
document.getElementById("firstCb").onclick = function () {
//2.获取下边列表中所有的cb
var cbs = document.getElementsByName("uid");
//3.遍历
for (var i = 0; i < cbs.length; i++) {
//4.设置这些cbs[i]的checked状态 = firstCb.checked
cbs[i].checked = this.checked;
}
}
}
</script>
</head>
<body>
<div class="container">
<h3 style="text-align: center">用户信息列表</h3>
<div style="float: left;">
<form class="form-inline" action="${pageContext.request.contextPath}/findUserByPageServlet" method="post">
<div class="form-group">
<label for="exampleInputName2">姓名</label>
<input type="text" name="name" value="${condition.name[0]}" class="form-control" id="exampleInputName2">
</div>
<div class="form-group">
<label for="exampleInputName3">籍贯</label>
<input type="text" name="address" value="${condition.address[0]}" class="form-control"
id="exampleInputName3">
</div>
<div class="form-group">
<label for="exampleInputEmail2">邮箱</label>
<input type="text" name="email" value="${condition.email[0]}" class="form-control"
id="exampleInputEmail2">
</div>
<button type="submit" class="btn btn-default">查询</button>
</form>
</div>
<div style="float: right;margin: 5px;">
<a class="btn btn-primary" href="${pageContext.request.contextPath}/add.jsp">添加联系人</a>
<a class="btn btn-primary" href="javascript:void(0);" id="delSelected">删除选中</a>
</div>
<form id="form" action="${pageContext.request.contextPath}/delSelectedServlet" method="post">
<table border="1" class="table table-bordered table-hover">
<tr class="success">
<th><input type="checkbox" id="firstCb"></th>
<th>编号</th>
<th>姓名</th>
<th>性别</th>
<th>年龄</th>
<th>籍贯</th>
<th>QQ</th>
<th>邮箱</th>
<th>操作</th>
</tr>
<c:forEach items="${pb.list}" var="user" varStatus="s">
<tr>
<td><input type="checkbox" name="uid" value="${user.id}"></td>
<td>${s.count}</td>
<td>${user.name}</td>
<td>${user.gender}</td>
<td>${user.age}</td>
<td>${user.address}</td>
<td>${user.qq}</td>
<td>${user.email}</td>
<td>
<a class="btn btn-default btn-sm"
href="${pageContext.request.contextPath}/findUserServlet?id=${user.id}">修改</a>
<a class="btn btn-default btn-sm" href="javascript:deleteUser(${user.id});">删除</a>
</td>
</tr>
</c:forEach>
</table>
</form>
<div>
<nav aria-label="Page navigation">
<ul class="pagination">
<c:if test="${pb.currentPage == 1}">
<li class="disabled">
<a href="${pageContext.request.contextPath}/findUserByPageServlet?currentPage=1&rows=5&name=${condition.name[0]}&address=${condition.address[0]}&email=${condition.email[0]}"
aria-label="Previous">
<span aria-hidden="true">«</span>
</a>
</li>
</c:if>
<c:if test="${pb.currentPage != 1}">
<li>
<a href="${pageContext.request.contextPath}/findUserByPageServlet?currentPage=${pb.currentPage - 1}&rows=5&name=${condition.name[0]}&address=${condition.address[0]}&email=${condition.email[0]}"
aria-label="Previous">
<span aria-hidden="true">«</span>
</a>
</li>
</c:if>
<c:forEach begin="1" end="${pb.totalPage}" var="i">
<c:if test="${pb.currentPage == i}">
<li class="active"><a
href="${pageContext.request.contextPath}/findUserByPageServlet?currentPage=${i}&rows=5&name=${condition.name[0]}&address=${condition.address[0]}&email=${condition.email[0]}">${i}</a>
</li>
</c:if>
<c:if test="${pb.currentPage != i}">
<li>
<a href="${pageContext.request.contextPath}/findUserByPageServlet?currentPage=${i}&rows=5&name=${condition.name[0]}&address=${condition.address[0]}&email=${condition.email[0]}">${i}</a>
</li>
</c:if>
</c:forEach>
<c:if test="${pb.currentPage == pb.totalPage}">
<li class="disabled">
<a href="${pageContext.request.contextPath}/findUserByPageServlet?currentPage=${pb.totalPage}&rows=5&name=${condition.name[0]}&address=${condition.address[0]}&email=${condition.email[0]}"
aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li>
</c:if>
<c:if test="${pb.currentPage != pb.totalPage}">
<li>
<a href="${pageContext.request.contextPath}/findUserByPageServlet?currentPage=${pb.currentPage + 1}&rows=5&name=${condition.name[0]}&address=${condition.address[0]}&email=${condition.email[0]}"
aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li>
</c:if>
<span style="font-size: 25px;margin-left: 5px;">
共${pb.totalCount}条记录，共${pb.totalPage}页
</span>
</ul>
</nav>
</div>
</div>
</body>
</html>
FindUserByPageServlet
package cn.guizimo.little.web.servlet;
import cn.guizimo.little.domain.PageBean;
import cn.guizimo.little.domain.User;
import cn.guizimo.little.service.UserService;
import cn.guizimo.little.service.impl.UserServiceImpl;
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.util.Map;
@WebServlet("/findUserByPageServlet")
public class FindUserByPageServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
//1.获取参数
String currentPage = request.getParameter("currentPage");//当前页码
String rows = request.getParameter("rows");//每页显示条数
if(currentPage == null || "".equals(currentPage)){
currentPage = "1";
}
if(rows == null || "".equals(rows)){
rows = "5";
}
//获取条件查询参数
Map<String, String[]> condition = request.getParameterMap();
//2.调用service查询
UserService service = new UserServiceImpl();
PageBean<User> pb = service.findUserByPage(currentPage,rows,condition);
System.out.println(pb);
//3.将PageBean存入request
request.setAttribute("pb",pb);
request.setAttribute("condition",condition);//将查询条件存入request
//4.转发到list.jsp
request.getRequestDispatcher("/list.jsp").forward(request,response);
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
测试
条件查询
思路
主要是在sql语句的编写
jsp
<div style="float: left;">
<form class="form-inline" action="${pageContext.request.contextPath}/findUserByPageServlet" method="post">
<div class="form-group">
<label for="exampleInputName2">姓名</label>
<input type="text" name="name" value="${condition.name[0]}" class="form-control" id="exampleInputName2">
</div>
<div class="form-group">
<label for="exampleInputName3">籍贯</label>
<input type="text" name="address" value="${condition.address[0]}" class="form-control"
id="exampleInputName3">
</div>
<div class="form-group">
<label for="exampleInputEmail2">邮箱</label>
<input type="text" name="email" value="${condition.email[0]}" class="form-control"
id="exampleInputEmail2">
</div>
<button type="submit" class="btn btn-default">查询</button>
</form>
</div>
dao层方法
@Override
public int findTotalCount(Map<String, String[]> condition) {
//1.定义模板初始化sql
String sql = "select count(*) from user where 1 = 1 ";
StringBuilder sb = new StringBuilder(sql);
//2.遍历map
Set<String> keySet = condition.keySet();
//定义参数的集合
List<Object> params = new ArrayList<Object>();
for (String key : keySet) {
//排除分页条件参数
if("currentPage".equals(key) || "rows".equals(key)){
continue;
}
//获取value
String value = condition.get(key)[0];
//判断value是否有值
if(value != null && !"".equals(value)){
//有值
sb.append(" and "+key+" like ? ");
params.add("%"+value+"%");//？条件的值
}
}
System.out.println(sb.toString());
System.out.println(params);
return template.queryForObject(sb.toString(),Integer.class,params.toArray());
}
@Override
public List<User> findByPage(int start, int rows, Map<String, String[]> condition) {
String sql = "select * from user where 1 = 1 ";
StringBuilder sb = new StringBuilder(sql);
//2.遍历map
Set<String> keySet = condition.keySet();
//定义参数的集合
List<Object> params = new ArrayList<Object>();
for (String key : keySet) {
//排除分页条件参数
if("currentPage".equals(key) || "rows".equals(key)){
continue;
}
//获取value
String value = condition.get(key)[0];
//判断value是否有值
if(value != null && !"".equals(value)){
//有值
sb.append(" and "+key+" like ? ");
params.add("%"+value+"%");//？条件的值
}
}
//添加分页查询
sb.append(" limit ?,? ");
//添加分页查询参数值
params.add(start);
params.add(rows);
sql = sb.toString();
System.out.println(sql);
System.out.println(params);
return template.query(sql,new BeanPropertyRowMapper<User>(User.class),params.toArray());
}
测试
感谢
黑马程序员
万能的网络
以及勤劳的自己
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