JavaWeb - 综合练习

综合练习：

　　1. 简单功能

　　　　1. 列表查询

　　　　2. 登录

　　　　3. 添加

　　　　4. 删除

　　　　5. 修改

　　2. 复杂功能

　　　　1. 删除选中

　　　　2. 分页查询

　　　　　　1. 减轻服务器内存的开销

　　　　　　2. 提升用户体验

（2）

　　　　3. 复杂条件查询

##登录功能

　　1. 调整页面，加入验证码功能

# 整体思路设计：

　　1. 设计页面布局，通过form表单传输参数到Servlet页面

　　2. Servlet页面设置编码、接收参数，根据参数和功能要求找到Service页面，Service页面根据需求将参数和条件传递到Dao页面进行数据处理

　　3. Dao页面编写核心sql，将数据包装后返回

　　4. Servlet页面拿到数据后通过转发和重定向让页面数据回显或跳转页面

　　5. 在前端页面通过JSTL和EL表达式获取域中的数据，放置到页面中

登录的login页面：

<%@ 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">
        //切换验证码
        function refreshCode() {
            //获取验证码的图片对象
            var vcode = document.getElementById("vcode");

            //设置其src属性，加时间戳
            vcode.src = "${pageContext.request.contextPath}/checkCodeServlet?time"+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>&times;</span></button>
        <strong>${login_msg}</strong>
    </div>
</div>
</body>
</html>

进行登录页面的loginServlet页面：

package web.servlet;

import domain.User;
import org.apache.commons.beanutils.BeanUtils;
import service.UserService;
import 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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.util.Map;

@WebServlet("/loginServlet")
public class LoginServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // 1.设置编码
        request.setCharacterEncoding("utf-8");
        // 2. 获取数据
        String verifycode = request.getParameter("verifycode");

        // 3. 验证码校验
        HttpSession session = request.getSession();
        String check_code =(String) session.getAttribute("check_code");

        //确保验证码一次性
        session.removeAttribute("check_code");

        if(!check_code.equalsIgnoreCase(verifycode)){
            //验证码不正确
            //提示信息，跳转登录页面
            request.setAttribute("login_msg","验证码错误！");
            request.getRequestDispatcher("/login.jsp").forward(request,response);
        }
        // 3.封装user对象
        Map<String, String[]> map = request.getParameterMap();
        User user = new User();
        try {
            BeanUtils.populate(user,map);
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }


        // 5. 调用Service查询
        UserService service = new UserServiceImpl();
        User login_user = service.login(user);
        // 6. 判断是否登录成功
        if(login_user!=null){
            //登录成功
            // 将用户存入session，跳转页面
            session.setAttribute("user",login_user);
            response.sendRedirect(request.getContextPath()+"/index.jsp");
        }else {
            //登录失败
            request.setAttribute("login_msg","用户名或密码错误");
            request.getRequestDispatcher("/login.jsp").forward(request,response);
        }

    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
}

loginServlet

index主页面：

<%@ 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>首页</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">
  </script>
</head>
<body>
<div align="center" style="font-size: 25px">${user.name},欢迎您</div>
<div align="center">
  <a
          href="${pageContext.request.contextPath}/findUserByPageServlet" style="text-decoration:none;font-size:33px">查询所有用户信息
  </a>
</div>
</body>
</html>

index.jsp

查看用户列表的Servlet：

package web.servlet;

import domain.PageBean;
import domain.User;
import service.UserService;
import 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");//每页显示的条数
        if(currentPage==null||"".equals(currentPage)){
            currentPage="1";
        }

        if(rows==null || "".equals(rows)){
            rows = "5";
        }

        // 获取条件查询的参数
        Map<String, String[]> condition = request.getParameterMap();


        //2. 调用service
        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);
        // 将查询条件也存入，方便回显
        request.setAttribute("condition",condition);

        //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);
    }
}

findUserByPageServlet

点击查看所有列表的list页面：

<%@ 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>
        //删除时弹出提示框
        function delUser(id) {
            if(confirm("您确定要删除吗")){
                //访问路径
                location.href = "${pageContext.request.contextPath}/delServlet?id=" + id;
            }
        }
        window.onload = function () {
            //给删除选中按钮添加单击事件
            document.getElementById("delSelected").onclick = function () {
                //删除确认
                if (confirm("您确定要删除选中条目吗？")) {
                    var flag = false;//用于判断是否有条目被选中，防止空指针异常
                    // 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){
                            //表示有一个条目选中了
                            flag = true;
                            break;
                        }
                    }
                    if(flag) {//有条目被选中
                        //将所有选了的表单提交
                        document.getElementById("delForm").submit();
                    }
                }
            }
            };
            // 全选全不选的勾勾
            document.getElementById("firstCb").onclick = function () {
                // 获取下面列表中所有的Cb
                var cbs = document.getElementsByName("uid");
                // 遍历
                for(var i = 0; i < cbs.length ;i++){
                    //设置这些cbs[i]的checked状态等于firstCb的checked状态
                    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="${pageContext.request.contextPath}/findUserByPageServlet" method="post">
            <div class="form-group" style="margin-left: 5px">
                <label for="exampleInputName2">姓名</label>
                <input type="text" class="form-control" id="exampleInputName2" name="name" value="${condition.name[0]}" >
            </div>
            <div class="form-group" style="margin-left: 5px">
                <label for="exampleInputName3">籍贯</label>
                <input type="text" class="form-control" id="exampleInputName3" name="address" value="${condition.address[0]}">
            </div>
            <div class="form-group" style="margin-left: 5px">
                <label for="exampleInputEmail2">邮箱</label>
                <input type="email" class="form-control" id="exampleInputEmail2" name="email" value="${condition.email[0]}">
            </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="${pageContext.request.contextPath}/add.jsp">添加联系人</a>
        <%--给删除选中按钮加单击事件，使其提交复选框选中的id表单--%>
        <a class="btn btn-primary" href="javascript:void(0);" id="delSelected">删除选中</a>
    </div>
    <%--将复选框的id用表单的形式提交--%>
    <form id="delForm" action="${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="${pb.list}" var="user" varStatus="s">
            <tr>
                <th><input type="checkbox" name="uid" value="${user.id}"></th>
                <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=${user.id}">修改</a>&nbsp;
                    <a class="btn btn-default btn-sm" href="javascript:delUser(${user.id});">删除</a></td>
            </tr>
        </c:forEach>
    </table>
    </form>

    <%--分页工具条--%>
    <div>
        <nav aria-label="Page navigation">
            <ul class="pagination">
                <%--第一页时前一页不可选--%>
                <c:if test="${pb.currentPage==1}">
                    <li class="disabled">
                            <%--上一页--%>
                        <a href="#" aria-label="${pageContext.request.contextPath}/findUserByPageServlet?currentPage=${pb.currentPage -1}&rows=5&name=${condition.name[0]}&address=${condition.address[0]}&email=${condition.email[0]}">
                            <span aria-hidden="true">&laquo;</span>
                        </a>
                    </li>
                </c:if>
                <c:if test="${pb.currentPage!=1}">
                    <li>
                            <%--上一页--%>
                        <a href="#" aria-label="${pageContext.request.contextPath}/findUserByPageServlet?currentPage=${pb.currentPage -1}&rows=5&name=${condition.name[0]}&address=${condition.address[0]}&email=${condition.email[0]}">
                            <span aria-hidden="true">&laquo;</span>
                        </a>
                    </li>
                </c:if>
                <%--页码的获取--%>
                <c:forEach begin="1" end="${pb.totalPage}" var="i">
                    <%--为页码添加激活状态--%>
                    <c:if test="${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]}"> ${i} </a></li>
                    </c:if>
                    <%--为页码添加激活状态--%>
                    <c:if test="${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>

                <li>
                    <%--下一页--%>
                    <a href="${pageContext.request.contextPath}/findUserByPageServlet?currentPage=${pb.currentPage +1}&rows=5" aria-label="Next">
                        <span aria-hidden="true">&raquo;</span>
                    </a>
                </li>
                <span style="font-size: 25px; margin-left: 8px">
                    共${pb.totalCount}条记录，共${pb.totalPage}页
                </span>
            </ul>
        </nav>
    </div>

</div>
</body>
</html>

list.jsp

list页面点击修改数据后跳转到的查找用户信息并回显的Servlet：

package web.servlet;

import domain.User;
import service.UserService;
import 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 {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String id = request.getParameter("id");
        UserService service = new UserServiceImpl();
        // 在数据库中查找到该id的用户
        User user = service.findUser(id);
        // 将该用户封装到user里
        request.setAttribute("user",user);
        //传递到显示信息的更新的jsp
        request.getRequestDispatcher("/update.jsp").forward(request,response);
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
}

findUserServlet

回显信息，并且提供修改数据页面的jsp：

<%@ 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="${pageContext.request.contextPath}/updateServlet" method="post">
        <%--隐藏域--%>
        <input type="hidden" name="id" value="${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>
            <%--先通过JSTL判断性别，在设置checked属性--%>
            <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" id="age"  name="age" placeholder="请输入年龄" value="${user.age}" />
        </div>

        <div class="form-group">
            <label for="address">籍贯：</label>
            <select name="address" class="form-control" id="address" >
                <c:if test="${user.address == '广东'}">
                    <option value="广东" selected="selected">广东</option>
                    <option value="广西">广西</option>
                    <option value="湖南">湖南</option>
                </c:if>
                <c:if test="${user.address == '湖南'}">
                    <option value="广东">广东</option>
                    <option value="广西">广西</option>
                    <option value="湖南" selected="selected">湖南</option>
                </c:if>
                <c:if test="${user.address == '广西'}">
                    <option value="广东" >广东</option>
                    <option value="广西" selected="selected">广西</option>
                    <option value="湖南">湖南</option>
                </c:if>
                <c:if test="${user.address != '广西' and user.address!= '广东' and user.address!= '湖南'}">
                    <option value="广东" >广东</option>
                    <option value="广西">广西</option>
                    <option value="湖南">湖南</option>
                    <option value="${user.address}" selected="selected">${user.address}</option>
                </c:if>

            </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" id="qq" value="${user.qq}"/>
        </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" id="email" value="${user.email}"/>
        </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>

update.jsp

进行update信息接收的Servlet：

package web.servlet;

import domain.User;
import org.apache.commons.beanutils.BeanUtils;
import service.UserService;
import 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.lang.reflect.InvocationTargetException;
import java.util.Map;

@WebServlet("/updateServlet")
public class updateServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("utf-8");
        Map<String, String[]> map = request.getParameterMap();
        User user = new User();
        try {
            BeanUtils.populate(user,map);
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }
        UserService service = new UserServiceImpl();
        service.updateUser(user);
        //重定向到用户列表，展示更新的数据
        response.sendRedirect(request.getContextPath()+"/userListServlet");
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
}

updateServlet

将更新的信息封装到user里传递给UserListServlet后，该Servlet将数据重新更新到list.jsp页面

package web.servlet;

import domain.User;
import service.UserService;
import 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 {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // 1. 调用UserService完成查询
        UserService service = new UserServiceImpl();
        List<User> users = service.findAll();
        // 2.将list存进request域
        request.setAttribute("users",users);
        //3. 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);
    }
}

UserListServlet

list页面提供的添加联系人的jsp：

<%@ 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}/addServlet" 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="jiguan">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" id="qq" 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" id="email"/>
        </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>

add.jsp

进行添加信息的Servlet：

package web.servlet;

import domain.User;
import org.apache.commons.beanutils.BeanUtils;
import service.UserService;
import 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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.util.Map;

@WebServlet("/addServlet")
public class addServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        request.setCharacterEncoding("utf-8");
        Map<String, String[]> map = request.getParameterMap();
        User user = new User();
        try {
            BeanUtils.populate(user,map)A;
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }
        UserService service = new UserServiceImpl();
        service.add(user);
        response.sendRedirect(request.getContextPath()+"/userListServlet");
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
}

addServlet

list页面提供删除按钮连接的Serlvet：

package web.servlet;

import service.UserService;
import 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("/delServlet")
public class delServlet extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("utf-8");
        String id = request.getParameter("id");
        UserService service = new UserServiceImpl();
        service.del(id);

        response.sendRedirect(request.getContextPath()+"/userListServlet");
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
}

delServlet

list页面提供的删除选中处理的Servlet：

package web.servlet;

import service.UserService;
import 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 {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        request.setCharacterEncoding("utf-8");
        String[] uids = request.getParameterValues("uid");
        UserService service = new UserServiceImpl();
        service.delSelectedUser(uids);
        response.sendRedirect(request.getContextPath()+"/userListServlet");
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        this.doPost(request, response);
    }
}

delSelectedServlet

domain包中封装的用来进行分页查询的PageBean实体类：

package domain;

import java.util.List;

/**
 * 分页对象
 */
public class PageBean<T> {
    private int totalCount; //总记录数
    private int totalPage;  //总页码
    private List<T> list; // 每页的数据
    private int currentPage; //当前页码
    private int rows; // 每页显示的记录数

    public int getTotalCount() {
        return totalCount;
    }

    public void setTotalCount(int totalCount) {
        this.totalCount = totalCount;
    }

    public int getTotalPage() {
        return totalPage;
    }

    public void setTotalPage(int totalPage) {
        this.totalPage = totalPage;
    }

    public List<T> getList() {
        return list;
    }

    public void setList(List<T> list) {
        this.list = list;
    }

    public int getCurrentPage() {
        return currentPage;
    }

    public void setCurrentPage(int currentPage) {
        this.currentPage = currentPage;
    }

    public int getRows() {
        return rows;
    }

    public void setRows(int rows) {
        this.rows = rows;
    }

    @Override
    public String toString() {
        return "PageBean{" +
                "totalCount=" + totalCount +
                ", totalPage=" + totalPage +
                ", list=" + list +
                ", currentPage=" + currentPage +
                ", rows=" + rows +
                '}';
    }
}

PageBean.java

domain包下封装的User实体类：

package domain;

public class User {
    private int id;
    private String name;
    private String gender;
    private int age;
    private String address;
    private String qq;
    private String email;
    private String username;
    private String password;

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getGender() {
        return gender;
    }

    public void setGender(String gender) {
        this.gender = gender;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getQq() {
        return qq;
    }

    public void setQq(String qq) {
        this.qq = qq;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", gender='" + gender + '\'' +
                ", age=" + age +
                ", address='" + address + '\'' +
                ", qq='" + qq + '\'' +
                ", email='" + email + '\'' +
                ", username='" + username + '\'' +
                ", password='" + password + '\'' +
                '}';
    }
}

User.java

service包下的UserService接口：

package service;

import domain.PageBean;
import domain.User;

import java.util.List;
import java.util.Map;

/**
 * 用户管理的业务接口
 */
public interface UserService {
    /**
     * 查询所有用户信息
     * @return
     */
    public List<User> findAll();

    /**
     * 用户登录
     * @param user
     * @return
     */
    public User login(User user);

    /**
     * 添加用户
     * @param user
     * @return
     */
    public void add(User user);

    /**
     * 根据id删除
     * @param id
     */
    public void del(String id);

    /**
     * 根据id找用户
     * @param id
     * @return
     */
    User findUser(String id);

    void updateUser(User user);

    /**
     * 批量删除用户
     * @param uids
     */
    void delSelectedUser(String[] uids);

    /**
     * 分页条件查询
     * @param currentPage
     * @param rows
     * @param condition
     * @return
     */
    PageBean<User> findUserByPage(String currentPage, String rows, Map<String, String[]> condition);
}

UserService.interface

service包下UserService接口的实现类：

package service.impl;

import dao.UserDao;
import dao.impl.UserDaoImpl;
import domain.PageBean;
import domain.User;
import service.UserService;

import java.util.List;
import java.util.Map;

public class UserServiceImpl implements UserService{
    UserDao dao = new UserDaoImpl();
    @Override
    public List<User> findAll() {
        //调用dao来完成查询
        return dao.findAll();
    }

    @Override
    public User login(User user) {
        return dao.findUserByUsernameAndPassword(user.getUsername(),user.getPassword());
    }

    @Override
    public void add(User user) {
        dao.add(user);
    }

    @Override
    public void del(String id) {
        dao.del(Integer.parseInt(id));
    }

    @Override
    public User findUser(String id) {
        return dao.findUserById(Integer.parseInt(id));
    }

    @Override
    public void updateUser(User user) {
        dao.updateUser(user);
    }

    @Override
    public void delSelectedUser(String[] uids) {
        if (uids != null && uids.length > 0) {
            // 1. 遍历数组
            for (String uid : uids) {
                dao.del(Integer.parseInt(uid));
            }
        }
    }

    @Override
    public PageBean<User> findUserByPage(String _currentPage, String _rows, Map<String, String[]> condition) {
        int currentPage = Integer.parseInt(_currentPage);
        int rows = Integer.parseInt(_rows);

        // 使第一页原地跳转
        if(currentPage<=0){
            currentPage=1;
        }
        //1. 创建一个空的pageBean对象
        PageBean<User> pb = new PageBean<User>();

        //2. 设置参数
        pb.setCurrentPage(currentPage);
        pb.setRows(rows);

        //3. 调用dao查询总记录数
        int totalCount = dao.findTotalCount(condition);
        pb.setTotalCount(totalCount);

        //4. 调用dao查询List集合
        //计算开始的记录索引
        int start = (currentPage - 1) * rows;
        List<User> list = dao.findByPage(start,rows,condition);
        pb.setList(list);

        //5. 计算总页码
        int totalPage = (totalCount % rows) == 0 ? totalCount/rows : (totalCount/rows) + 1;
        pb.setTotalPage(totalPage);

        return pb;

    }
}

UserServiceImpl

dao包下UserDao接口：

package dao;

import domain.User;

import java.util.List;
import java.util.Map;

/**
 * 用户操作的DAO
 */
public interface UserDao {
    public List<User> findAll();
    public User findUserByUsernameAndPassword(String username,String password);
    public void add(User user);
    public void del(int id);

    User findUserById(int id);

    void updateUser(User user);

    /**
     * 查询总记录数
     * @return
     * @param condition
     */
    int findTotalCount(Map<String, String[]> condition);

    /**
     * 分页查询每页记录
     * @param start
     * @param rows
     * @param condition
     * @return
     */
    List<User> findByPage(int start, int rows, Map<String, String[]> condition);
}

UserDao.interface

dao包下UserDao的实现类：

package dao.impl;

import dao.UserDao;
import domain.User;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import util.JDBCUtils;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class UserDaoImpl implements UserDao {
    private JdbcTemplate template = new JdbcTemplate(JDBCUtils.getDataSource());
    @Override
    public List<User> findAll() {
        // 使用JDBC操作数据库
        //1.定义sql
        String sql = "select * from user";
        List<User> users = template.query(sql, new BeanPropertyRowMapper<User>(User.class));

        return users;
    }

    @Override
    public User findUserByUsernameAndPassword(String username,String password) {
        try{
        String sql = "select * from user where username =? and password = ?";

            User login_user = template.queryForObject(sql, new BeanPropertyRowMapper<User>(User.class),username,password);
            return login_user;
        }catch (Exception e){
            e.printStackTrace();
            return null;
        }
    }

    @Override
    public void add(User user) {
        String name = user.getName();
        String gender = user.getGender();
        int age = user.getAge();
        String address = user.getAddress();
        String qq = user.getQq();
        String email = user.getEmail();

        String sql = "insert into user values(null,?,?,?,?,?,?,null,null)";
        template.update(sql,name,gender,age,address,qq,email);
    }

    @Override
    public void del(int id) {
        String sql = "delete from user where id = ?";
        template.update(sql,id);
    }

    @Override
    public User findUserById(int id) {
        String sql = "select * from user where id = ?";
        User user = template.queryForObject(sql, new BeanPropertyRowMapper<User>(User.class), id);
        return user;
    }

    @Override
    public void updateUser(User user) {
        String sql = "update user set name = ?,gender = ?,age = ?,address = ?,qq = ?,email = ? where id = ?";
        template.update(sql,user.getName(),user.getGender(),user.getAge(),user.getAddress(),user.getQq(),user.getEmail(),user.getId());
    }

    @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，后期将value放入
        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,注意空格
                sb.append(" and " + key+ " like ? ");
                //加了几次，就加入集合几个value
                params.add("%"+value+"%");//？条件的参数
            }
        }
        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，后期将value放入
        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,注意空格
                sb.append(" and " + key+ " like ? ");
                //加了几次，就加入集合几个value
                params.add("%"+value+"%");//？条件的参数
            }
        }

        //添加分页的查询
        sb.append(" limit ?, ?");
        //添加分页查询的参数
        params.add(start);
        params.add(rows);

        sql = sb.toString();
        return template.query(sql,new BeanPropertyRowMapper<User>(User.class),params.toArray());
    }
}

UserDaoImpl

util包下对JDBCTemplate工具类进行的封装：

package util;

import com.alibaba.druid.pool.DruidDataSourceFactory;

import javax.sql.DataSource;
import javax.xml.crypto.Data;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

/**
 * JDBC工具类 使用Durid连接池
 */
public class JDBCUtils {

    private static DataSource ds ;

    static {

        try {
            //1.加载配置文件
            Properties pro = new Properties();
            //使用ClassLoader加载配置文件，获取字节输入流
            InputStream is = JDBCUtils.class.getClassLoader().getResourceAsStream("druid.properties");
            pro.load(is);

            //2.初始化连接池对象
            ds = DruidDataSourceFactory.createDataSource(pro);

        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 获取连接池对象
     */
    public static DataSource getDataSource(){
        return ds;
    }


    /**
     * 获取连接Connection对象
     */
    public static Connection getConnection() throws SQLException {
        return  ds.getConnection();
    }
}

JDBCUtils工具类

数据库连接的配置properties：

driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql://127.0.0.1:3306/day17
username=root
password=woaini1314
# 初始化连接数量
initialSize=5
# 最大连接数
maxActive=10
# 最大等待时间
maxWait=3000

druid.properties

posted @ 2020-08-06 10:03 五号世界阅读(365) 评论(0) 编辑收藏举报

会员力量，点亮园子希望

刷新页面返回顶部

五号世界

JavaWeb - 综合练习

综合练习：

1. 简单功能

1. 列表查询

2. 登录

3. 添加

4. 删除

5. 修改

2. 复杂功能

1. 删除选中

2. 分页查询

1. 减轻服务器内存的开销

2. 提升用户体验

3. 复杂条件查询

##登录功能

1. 调整页面，加入验证码功能

# 整体思路设计：

1. 设计页面布局，通过form表单传输参数到Servlet页面

2. Servlet页面设置编码、接收参数，根据参数和功能要求找到Service页面，Service页面根据需求将参数和条件传递到Dao页面进行数据处理

3. Dao页面编写核心sql，将数据包装后返回

4. Servlet页面拿到数据后通过转发和重定向让页面数据回显或跳转页面

5. 在前端页面通过JSTL和EL表达式获取域中的数据，放置到页面中

登录的login页面：

进行登录页面的loginServlet页面：

index主页面：

查看用户列表的Servlet：

点击查看所有列表的list页面：

list页面点击修改数据后跳转到的查找用户信息并回显的Servlet：

回显信息，并且提供修改数据页面的jsp：

进行update信息接收的Servlet：

将更新的信息封装到user里传递给UserListServlet后，该Servlet将数据重新更新到list.jsp页面

list页面提供的添加联系人的jsp：

进行添加信息的Servlet：

list页面提供删除按钮连接的Serlvet：

list页面提供的删除选中处理的Servlet：

domain包中封装的用来进行分页查询的PageBean实体类：

domain包下封装的User实体类：

service包下的UserService接口：

service包下UserService接口的实现类：

dao包下UserDao接口：

dao包下UserDao的实现类：

util包下对JDBCTemplate工具类进行的封装：

数据库连接的配置properties：

公告

　　1. 简单功能

　　　　1. 列表查询

　　　　2. 登录

　　　　3. 添加

　　　　4. 删除

　　　　5. 修改

　　2. 复杂功能

　　　　1. 删除选中

　　　　2. 分页查询

　　　　　　1. 减轻服务器内存的开销

　　　　　　2. 提升用户体验

　　　　3. 复杂条件查询

　　1. 调整页面，加入验证码功能

　　1. 设计页面布局，通过form表单传输参数到Servlet页面

　　2. Servlet页面设置编码、接收参数，根据参数和功能要求找到Service页面，Service页面根据需求将参数和条件传递到Dao页面进行数据处理

　　3. Dao页面编写核心sql，将数据包装后返回

　　4. Servlet页面拿到数据后通过转发和重定向让页面数据回显或跳转页面

　　5. 在前端页面通过JSTL和EL表达式获取域中的数据，放置到页面中