三層架構：軟件設計架構
- 界面層(表示層)：用戶看的得界面。用戶可以通過界面上的組件和服務器進行交互
- 業務邏輯層：處理業務邏輯的。
- 數據訪問層：操作數據存儲文件。
三層架構與MVC相似但有區別
開發前的準備工作
1. 需求：用戶信息的增刪改查操作
2. 設計：
1. 技術選型：Servlet+JSP+MySQL+JDBCTempleat+Duird+BeanUtilS+tomcat
2. 數據庫設計：
create database day17; -- 創建數據庫
use day17; -- 使用數據庫
create table user( -- 創建表
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)
);
3. 開發：
1. 環境搭建
1. 創建數據庫環境
2. 創建項目，導入需要的jar包
2. 編碼
4. 測試
5. 部署運維
綜合練習：簡單功能
-
列表查詢
![在這裏插入圖片描述]()
-
登錄
-
添加
4. 刪除
5. 修改
綜合練習：複雜功能
- 刪除選中
![在這裏插入圖片描述]()
- 分頁查詢
複雜條件分頁查詢
- 分頁查詢好處：
1. 減輕服務器內存的開銷
2. 提升用戶體驗
- 複雜條件查詢
項目工程結構
dao層用來操作數據庫
domain文件夾是兩個javabean類，含有PageBean和User類
service服務層含一個用戶服務的接口和對應實現類
utils文件夾是JDBCUtils工具類便於數據庫連接，JDBC工具類 使用Durid連接池
servlet用於接收前端的請求
web文件夾，存放前端的東西，如js，fonts，jsp頁面等
項目運行邏輯
- 首先運行好tomcat服務器，用戶來到首頁login.jsp
<%@ 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>管理員登錄</title>
<!-- 1. 導入CSS的全局樣式 -->
<link href="css/bootstrap.min.css" rel="stylesheet">
<!-- 2. jQuery導入，建議使用1.9以上的版本 -->
<script src="js/jquery-2.1.0.min.js"></script>
<!-- 3. 導入bootstrap的js文件 -->
<script src="js/bootstrap.min.js"></script>
<script type="text/javascript">
//切換驗證碼
function refreshCode(){
//1.獲取驗證碼圖片對象
var vcode = document.getElementById("vcode");
//2.設置其src屬性，加時間戳
vcode.src = "${pageContext.request.contextPath}/checkCodeServlet?time="+new Date().getTime();
}
</script>
</head>
<body>
<div class="container" style="width: 400px;">
<h3 style="text-align: center;">管理員登錄</h3>
<form action="${pageContext.request.contextPath}/loginServlet" method="post">
<div class="form-group">
<label for="user">用戶名：</label>
<input type="text" name="username" class="form-control" id="user" placeholder="請輸入用戶名"/>
</div>
<div class="form-group">
<label for="password">密碼：</label>
<input type="password" name="password" class="form-control" id="password" placeholder="請輸入密碼"/>
</div>
<div class="form-inline">
<label for="vcode">驗證碼：</label>
<input type="text" name="verifycode" class="form-control" id="verifycode" placeholder="請輸入驗證碼" style="width: 120px;"/>
<a href="javascript:refreshCode();">
<img src="${pageContext.request.contextPath}/checkCodeServlet" title="看不清點擊刷新" id="vcode"/>
</a>
</div>
<hr/>
<div class="form-group" style="text-align: center;">
<input class="btn btn btn-primary" type="submit" value="登錄">
</div>
</form>
<!-- 出錯顯示的信息框 -->
<div class="alert alert-warning alert-dismissible" role="alert">
<button type="button" class="close" data-dismiss="alert" >
<span>×</span>
</button>
<strong>${login_msg}</strong>
</div>
</div>
</body>
</html>
- 用戶輸入用戶名，密碼，驗證碼跳轉到loginservlet
package cn.itcast.web.servlet;
import cn.itcast.domain.User;
import cn.itcast.service.UserService;
import cn.itcast.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 {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//1.設置編碼
request.setCharacterEncoding("utf-8");
//2.獲取數據
//2.1獲取用戶填寫驗證碼
String verifycode = request.getParameter("verifycode");
//3.驗證碼校驗
HttpSession session = request.getSession();
String checkcode_server = (String) session.getAttribute("CHECKCODE_SERVER");
session.removeAttribute("CHECKCODE_SERVER");//確保驗證碼一次性
if(!checkcode_server.equalsIgnoreCase(verifycode)){
//驗證碼不正確
//提示信息
request.setAttribute("login_msg","驗證碼錯誤！");
//跳轉登錄頁面
request.getRequestDispatcher("/login.jsp").forward(request,response);
return;
}
Map<String, String[]> map = request.getParameterMap();
//4.封裝User對象
User user = new User();
try {
BeanUtils.populate(user,map);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
//5.調用Service查詢
UserService service = new UserServiceImpl();
User loginUser = service.login(user);
//6.判斷是否登錄成功
if(loginUser != null){
//登錄成功
//將用戶存入session
session.setAttribute("user",loginUser);
//跳轉頁面
response.sendRedirect(request.getContextPath()+"/index.jsp");
}else{
//登錄失敗
//提示信息
request.setAttribute("login_msg","用戶名或密碼錯誤！");
//跳轉登錄頁面
request.getRequestDispatcher("/login.jsp").forward(request,response);
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
- 如果用戶驗證碼輸入錯誤，則可以更換驗證碼，跳轉到checkcodeservlet
package cn.itcast.web.servlet;
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;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;
/**
* 驗證碼
*/
@WebServlet("/checkCodeServlet")
public class CheckCodeServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {
//服務器通知瀏覽器不要緩存
response.setHeader("pragma","no-cache");
response.setHeader("cache-control","no-cache");
response.setHeader("expires","0");
//在內存中創建一個長80，寬30的圖片，默認黑色背景
//參數一：長
//參數二：寬
//參數三：顏色
int width = 80;
int height = 30;
BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
//獲取畫筆
Graphics g = image.getGraphics();
//設置畫筆顏色爲灰色
g.setColor(Color.GRAY);
//填充圖片
g.fillRect(0,0, width,height);
//產生4個隨機驗證碼，12Ey
String checkCode = getCheckCode();
//將驗證碼放入HttpSession中
request.getSession().setAttribute("CHECKCODE_SERVER",checkCode);
//設置畫筆顏色爲黃色
g.setColor(Color.YELLOW);
//設置字體的小大
g.setFont(new Font("黑體",Font.BOLD,24));
//向圖片上寫入驗證碼
g.drawString(checkCode,15,25);
//將內存中的圖片輸出到瀏覽器
//參數一：圖片對象
//參數二：圖片的格式，如PNG,JPG,GIF
//參數三：圖片輸出到哪裏去
ImageIO.write(image,"PNG",response.getOutputStream());
}
/**
* 產生4位隨機字符串
*/
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++){
//產生0到size-1的隨機值
int index = r.nextInt(size);
//在base字符串中獲取下標爲index的字符
char c = base.charAt(index);
//將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);
}
}
- 登陸成功以後，來到index.jsp，點擊查詢用戶所有信息，跳轉到findUserByPageServlet
index.jsp如下
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!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>首頁</title>
<!-- 1. 導入CSS的全局樣式 -->
<link href="css/bootstrap.min.css" rel="stylesheet">
<!-- 2. jQuery導入，建議使用1.9以上的版本 -->
<script src="js/jquery-2.1.0.min.js"></script>
<!-- 3. 導入bootstrap的js文件 -->
<script src="js/bootstrap.min.js"></script>
<script type="text/javascript">
</script>
</head>
<body>
<div >${user.name},歡迎您</div>
<div align="center">
<a
href="${pageContext.request.contextPath}/findUserByPageServlet" style="text-decoration:none;font-size:33px">查詢所有用戶信息
</a>
</div>
</body>
</html>
findUserByPageServlet如下，將查詢的結果轉發到list.jsp
package cn.itcast.web.servlet;
import cn.itcast.domain.PageBean;
import cn.itcast.domain.User;
import cn.itcast.service.UserService;
import cn.itcast.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.獲取參數
String currentPage = request.getParameter("currentPage");//當前頁碼
String rows = request.getParameter("rows");//每頁顯示條數
if(currentPage == null || "".equals(currentPage)){
currentPage = "1";
}
if(rows == null || "".equals(rows)){
rows = "5";
}
//獲取條件查詢參數
Map<String, String[]> condition = request.getParameterMap();
//2.調用service查詢
UserService service = new UserServiceImpl();
PageBean<User> pb = service.findUserByPage(currentPage,rows,condition);
System.out.println(pb);
//3.將PageBean存入request
request.setAttribute("pb",pb);
request.setAttribute("condition",condition);//將查詢條件存入request
//4.轉發到list.jsp
request.getRequestDispatcher("/list.jsp").forward(request,response);
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
- list.jsp如下，可以看到查詢的結果
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<!-- 網頁使用的語言 -->
<html lang="zh-CN">
<head>
<!-- 指定字符集 -->
<meta charset="utf-8">
<!-- 使用Edge最新的瀏覽器的渲染方式 -->
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<!-- viewport視口：網頁可以根據設置的寬度自動進行適配，在瀏覽器的內部虛擬一個容器，容器的寬度與設備的寬度相同。
width: 默認寬度與設備的寬度相同
initial-scale: 初始的縮放比，爲1:1 -->
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- 上述3個meta標籤*必須*放在最前面，任何其他內容都*必須*跟隨其後！ -->
<title>用戶信息管理系統</title>
<!-- 1. 導入CSS的全局樣式 -->
<link href="css/bootstrap.min.css" rel="stylesheet">
<!-- 2. jQuery導入，建議使用1.9以上的版本 -->
<script src="js/jquery-2.1.0.min.js"></script>
<!-- 3. 導入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){
//用戶安全提示
if(confirm("您確定要刪除嗎？")){
//訪問路徑
location.href="${pageContext.request.contextPath}/delUserServlet?id="+id;
}
}
window.onload = function(){
//給刪除選中按鈕添加單擊事件
document.getElementById("delSelected").onclick = function(){
if(confirm("您確定要刪除選中條目嗎？")){
var flag = false;
//判斷是否有選中條目
var cbs = document.getElementsByName("uid");
for (var i = 0; i < cbs.length; i++) {
if(cbs[i].checked){
//有一個條目選中了
flag = true;
break;
}
}
if(flag){//有條目被選中
//表單提交
document.getElementById("form").submit();
}
}
}
//1.獲取第一個cb
document.getElementById("firstCb").onclick = function(){
//2.獲取下邊列表中所有的cb
var cbs = document.getElementsByName("uid");
//3.遍歷
for (var i = 0; i < cbs.length; i++) {
//4.設置這些cbs[i]的checked狀態 = firstCb.checked
cbs[i].checked = this.checked;
}
}
}
</script>
</head>
<body>
<div class="container">
<h3 style="text-align: center">用戶信息列表</h3>
<div style="float: left;">
<form class="form-inline" action="${pageContext.request.contextPath}/findUserByPageServlet" method="post">
<div class="form-group">
<label for="exampleInputName2">姓名</label>
<input type="text" name="name" value="${condition.name[0]}" class="form-control" id="exampleInputName2" >
</div>
<div class="form-group">
<label for="exampleInputName3">籍貫</label>
<input type="text" name="address" value="${condition.address[0]}" class="form-control" id="exampleInputName3" >
</div>
<div class="form-group">
<label for="exampleInputEmail2">郵箱</label>
<input type="text" name="email" value="${condition.email[0]}" class="form-control" id="exampleInputEmail2" >
</div>
<button type="submit" class="btn btn-default">查詢</button>
</form>
</div>
<div style="float: right;margin: 5px;">
<a class="btn btn-primary" href="${pageContext.request.contextPath}/add.jsp">添加聯繫人</a>
<a class="btn btn-primary" href="javascript:void(0);" id="delSelected">刪除選中</a>
</div>
<form id="form" action="${pageContext.request.contextPath}/delSelectedServlet" method="post">
<table border="1" class="table table-bordered table-hover">
<tr class="success">
<th><input type="checkbox" id="firstCb"></th>
<th>編號</th>
<th>姓名</th>
<th>性別</th>
<th>年齡</th>
<th>籍貫</th>
<th>QQ</th>
<th>郵箱</th>
<th>操作</th>
</tr>
<c:forEach items="${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(${user.id});">刪除</a></td>
</tr>
</c:forEach>
</table>
</form>
<div>
<nav aria-label="Page navigation">
<ul class="pagination">
<c:if test="${pb.currentPage == 1}">
<li class="disabled">
</c:if>
<c:if test="${pb.currentPage != 1}">
<li>
</c:if>
<a href="${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: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]}">${i}</a></li>
</c:if>
</c:forEach>
<li>
<a href="${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>
<span style="font-size: 25px;margin-left: 5px;">
共${pb.totalCount}條記錄，共${pb.totalPage}頁
</span>
</ul>
</nav>
</div>
</div>
</body>
</html>
7.接着在list.jsp點擊刪除按鈕，可以刪除單條記錄，跳轉deluserservlet如下；
deluserservlet
package cn.itcast.web.servlet;
import cn.itcast.service.UserService;
import cn.itcast.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 {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//1.獲取id
String id = request.getParameter("id");
//2.調用service刪除
UserService service = new UserServiceImpl();
service.deleteUser(id);
//3.跳轉到查詢所有Servlet
response.sendRedirect(request.getContextPath()+"/userListServlet");
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
8而點擊刪除選中，可以刪掉選中的多條記錄DelSelectedServlet
package cn.itcast.web.servlet;
import cn.itcast.service.UserService;
import cn.itcast.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 {
//1.獲取所有id
String[] ids = request.getParameterValues("uid");
//2.調用service刪除
UserService service = new UserServiceImpl();
service.delSelectedUser(ids);
//3.跳轉查詢所有Servlet
response.sendRedirect(request.getContextPath()+"/userListServlet");
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
8點擊修改按鈕，跳轉到finduserServlet,再將查詢到的信息轉發回顯到update.jsp
finduserServlet
package cn.itcast.web.servlet;
import cn.itcast.domain.User;
import cn.itcast.service.UserService;
import cn.itcast.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 {
//1.獲取id
String id = request.getParameter("id");
//2.調用Service查詢
UserService service = new UserServiceImpl();
User user = service.findUserById(id);
//3.將user存入request
request.setAttribute("user",user);
//4.轉發到update.jsp
request.getRequestDispatcher("/update.jsp").forward(request,response);
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
update.jsp，在該頁面點擊跳轉updateUserServlet修改聯繫人生效
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<!-- 網頁使用的語言 -->
<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>修改用戶</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;">修改聯繫人</h3>
<form action="${pageContext.request.contextPath}/updateUserServlet" method="post">
<!-- 隱藏域 提交id-->
<input type="hidden" name="id" value="${user.id}">
<div class="form-group">
<label for="name">姓名：</label>
<input type="text" class="form-control" id="name" name="name" value="${user.name}" readonly="readonly" placeholder="請輸入姓名" />
</div>
<div class="form-group">
<label>性別：</label>
<c:if test="${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="${user.gender == '女'}">
<input type="radio" name="gender" value="男" />男
<input type="radio" name="gender" value="女" checked />女
</c:if>
</div>
<div class="form-group">
<label for="age">年齡：</label>
<input type="text" class="form-control" value="${user.age}" id="age" name="age" placeholder="請輸入年齡" />
</div>
<div class="form-group">
<label for="address">籍貫：</label>
<select name="address" id="address" class="form-control" >
<c:if test="${user.address == '陝西'}">
<option value="陝西" selected>陝西</option>
<option value="北京">北京</option>
<option value="上海">上海</option>
</c:if>
<c:if test="${user.address == '北京'}">
<option value="陝西" >陝西</option>
<option value="北京" selected>北京</option>
<option value="上海">上海</option>
</c:if>
<c:if test="${user.address == '上海'}">
<option value="陝西" >陝西</option>
<option value="北京">北京</option>
<option value="上海" selected>上海</option>
</c:if>
</select>
</div>
<div class="form-group">
<label for="qq">QQ：</label>
<input type="text" id="qq" class="form-control" value="${user.qq}" name="qq" placeholder="請輸入QQ號碼"/>
</div>
<div class="form-group">
<label for="email">Email：</label>
<input type="text" id="email" class="form-control" value="${user.email}" name="email" placeholder="請輸入郵箱地址"/>
</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>
updateUserServlet如下
package cn.itcast.web.servlet;
import cn.itcast.domain.User;
import cn.itcast.service.UserService;
import cn.itcast.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 {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//1.設置編碼
request.setCharacterEncoding("utf-8");
//2.獲取map
Map<String, String[]> map = request.getParameterMap();
//3.封裝對象
User user = new User();
try {
BeanUtils.populate(user,map);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
//4.調用Service修改
UserService service = new UserServiceImpl();
service.updateUser(user);
//5.跳轉到查詢所有Servlet
response.sendRedirect(request.getContextPath()+"/userListServlet");
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
最後是添加聯繫人功能，點擊添加聯繫人按鈕，跳轉到add.jsp，在add.jsp頁面裏面輸入添加的信息，然後再跳轉到addUserServlet
add.jsp如下：
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<!-- HTML5文檔-->
<!DOCTYPE html>
<!-- 網頁使用的語言 -->
<html lang="zh-CN">
<head>
<!-- 指定字符集 -->
<meta charset="utf-8">
<!-- 使用Edge最新的瀏覽器的渲染方式 -->
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<!-- viewport視口：網頁可以根據設置的寬度自動進行適配，在瀏覽器的內部虛擬一個容器，容器的寬度與設備的寬度相同。
width: 默認寬度與設備的寬度相同
initial-scale: 初始的縮放比，爲1:1 -->
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- 上述3個meta標籤*必須*放在最前面，任何其他內容都*必須*跟隨其後！ -->
<title>添加用戶</title>
<!-- 1. 導入CSS的全局樣式 -->
<link href="css/bootstrap.min.css" rel="stylesheet">
<!-- 2. jQuery導入，建議使用1.9以上的版本 -->
<script src="js/jquery-2.1.0.min.js"></script>
<!-- 3. 導入bootstrap的js文件 -->
<script src="js/bootstrap.min.js"></script>
</head>
<body>
<div class="container">
<center><h3>添加聯繫人頁面</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="請輸入姓名">
</div>
<div class="form-group">
<label>性別：</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">年齡：</label>
<input type="text" class="form-control" id="age" name="age" placeholder="請輸入年齡">
</div>
<div class="form-group">
<label for="address">籍貫：</label>
<select name="address" class="form-control" id="address">
<option value="陝西">陝西</option>
<option value="北京">北京</option>
<option value="上海">上海</option>
</select>
</div>
<div class="form-group">
<label for="qq">QQ：</label>
<input type="text" class="form-control" id="qq" name="qq" placeholder="請輸入QQ號碼"/>
</div>
<div class="form-group">
<label for="email">Email：</label>
<input type="text" class="form-control" id="email" name="email" placeholder="請輸入郵箱地址"/>
</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如下
package cn.itcast.web.servlet;
import cn.itcast.domain.User;
import cn.itcast.service.UserService;
import cn.itcast.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 {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//1.設置編碼
request.setCharacterEncoding("utf-8");
//2.獲取參數
Map<String, String[]> map = request.getParameterMap();
//3.封裝對象
User user = new User();
try {
BeanUtils.populate(user,map);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
//4.調用Service保存
UserService service = new UserServiceImpl();
service.addUser(user);
//5.跳轉到userListServlet
response.sendRedirect(request.getContextPath()+"/userListServlet");
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
對於dao層有一個接口和對應的實現類
package cn.itcast.dao;
import cn.itcast.domain.User;
import java.util.List;
import java.util.Map;
/**
* 用戶操作的DAO
*/
public interface UserDao {
public List<User> findAll();
User findUserByUsernameAndPassword(String username, String password);
void add(User user);
void delete(int id);
User findById(int i);
void update(User user);
/**
* 查詢總記錄數
* @return
* @param condition
*/
int findTotalCount(Map<String, String[]> condition);
/**
* 分頁查詢每頁記錄
* @param start
* @param rows
* @param condition
* @return
*/
List<User> findByPage(int start, int rows, Map<String, String[]> condition);
}
實現類
package cn.itcast.dao.impl;
import cn.itcast.dao.UserDao;
import cn.itcast.domain.User;
import cn.itcast.util.JDBCUtils;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
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操作數據庫...
//1.定義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 user = template.queryForObject(sql, new BeanPropertyRowMapper<User>(User.class), username, password);
return user;
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
@Override
public void add(User user) {
//1.定義sql
String sql = "insert into user values(null,?,?,?,?,?,?,null,null)";
//2.執行sql
template.update(sql, user.getName(), user.getGender(), user.getAge(), user.getAddress(), user.getQq(), user.getEmail());
}
@Override
public void delete(int id) {
//1.定義sql
String sql = "delete from user where id = ?";
//2.執行sql
template.update(sql, id);
}
@Override
public User findById(int id) {
String sql = "select * from user where id = ?";
return template.queryForObject(sql, new BeanPropertyRowMapper<User>(User.class), id);
}
@Override
public void update(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.定義模板初始化sql
String sql = "select count(*) from user where 1 = 1 ";
StringBuilder sb = new StringBuilder(sql);
//2.遍歷map
Set<String> keySet = condition.keySet();
//定義參數的集合
List<Object> params = new ArrayList<Object>();
for (String key : keySet) {
//排除分頁條件參數
if("currentPage".equals(key) || "rows".equals(key)){
continue;
}
//獲取value
String value = condition.get(key)[0];
//判斷value是否有值
if(value != null && !"".equals(value)){
//有值
sb.append(" and "+key+" like ? ");
params.add("%"+value+"%");//？條件的值
}
}
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.遍歷map
Set<String> keySet = condition.keySet();
//定義參數的集合
List<Object> params = new ArrayList<Object>();
for (String key : keySet) {
//排除分頁條件參數
if("currentPage".equals(key) || "rows".equals(key)){
continue;
}
//獲取value
String value = condition.get(key)[0];
//判斷value是否有值
if(value != null && !"".equals(value)){
//有值
sb.append(" and "+key+" like ? ");
params.add("%"+value+"%");//？條件的值
}
}
//添加分頁查詢
sb.append(" limit ?,? ");
//添加分頁查詢參數值
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());
}
}
domain層的兩個實體類，一個是PageBean，一個是User
package cn.itcast.domain;
import java.util.List;
/**
* 分頁對象
*/
public class PageBean<T> {
private int totalCount; // 總記錄數
private int totalPage ; // 總頁碼
private List<T> list ; // 每頁的數據
private int currentPage ; //當前頁碼
private int rows;//每頁顯示的記錄數
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 +
'}';
}
}
package cn.itcast.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 + '\'' +
'}';
}
}
service有一個userService接口，和實現類
package cn.itcast.service;
import cn.itcast.domain.PageBean;
import cn.itcast.domain.User;
import java.util.List;
import java.util.Map;
/**
* 用戶管理的業務接口
*/
public interface UserService {
/**
* 查詢所有用戶信息
* @return
*/
public List<User> findAll();
/**
* 登錄方法
* @param user
* @return
*/
User login(User user);
/**
* 保存User
* @param user
*/
void addUser(User user);
/**
* 根據id刪除User
* @param id
*/
void deleteUser(String id);
/**
* 根據id查詢
* @param id
* @return
*/
User findUserById(String id);
/**
* 修改用戶信息
* @param user
*/
void updateUser(User user);
/**
* 批量刪除用戶
* @param ids
*/
void delSelectedUser(String[] ids);
/**
* 分頁條件查詢
* @param currentPage
* @param rows
* @param condition
* @return
*/
PageBean<User> findUserByPage(String currentPage, String rows, Map<String, String[]> condition);
}
userservice實現類如下
package cn.itcast.service.impl;
import cn.itcast.dao.UserDao;
import cn.itcast.dao.impl.UserDaoImpl;
import cn.itcast.domain.PageBean;
import cn.itcast.domain.User;
import cn.itcast.service.UserService;
import java.util.List;
import java.util.Map;
public class UserServiceImpl implements UserService {
private UserDao dao = new UserDaoImpl();
@Override
public List<User> findAll() {
//調用Dao完成查詢
return dao.findAll();
}
@Override
public User login(User user) {
return dao.findUserByUsernameAndPassword(user.getUsername(),user.getPassword());
}
@Override
public void addUser(User user) {
dao.add(user);
}
@Override
public void deleteUser(String id) {
dao.delete(Integer.parseInt(id));
}
@Override
public User findUserById(String id) {
return dao.findById(Integer.parseInt(id));
}
@Override
public void updateUser(User user) {
dao.update(user);
}
@Override
public void delSelectedUser(String[] ids) {
if(ids != null && ids.length > 0){
//1.遍歷數組
for (String id : ids) {
//2.調用dao刪除
dao.delete(Integer.parseInt(id));
}
}
}
@Override
public PageBean<User> findUserByPage(String _currentPage, String _rows, Map<String, String[]> condition) {
int currentPage = Integer.parseInt(_currentPage);
int rows = Integer.parseInt(_rows);
if(currentPage <=0) {
currentPage = 1;
}
//1.創建空的PageBean對象
PageBean<User> pb = new PageBean<User>();
//2.設置參數
pb.setCurrentPage(currentPage);
pb.setRows(rows);
//3.調用dao查詢總記錄數
int totalCount = dao.findTotalCount(condition);
pb.setTotalCount(totalCount);
//4.調用dao查詢List集合
//計算開始的記錄索引
int start = (currentPage - 1) * rows;
List<User> list = dao.findByPage(start,rows,condition);
pb.setList(list);
//5.計算總頁碼
int totalPage = (totalCount % rows) == 0 ? totalCount/rows : (totalCount/rows) + 1;
pb.setTotalPage(totalPage);
return pb;
}
}
jdbc工具類代碼
package cn.itcast.util;
import com.alibaba.druid.pool.DruidDataSourceFactory;
import javax.sql.DataSource;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;
/**
* JDBC工具類 使用Durid連接池
*/
public class JDBCUtils {
private static DataSource ds ;
static {
try {
//1.加載配置文件
Properties pro = new Properties();
//使用ClassLoader加載配置文件，獲取字節輸入流
InputStream is = JDBCUtils.class.getClassLoader().getResourceAsStream("druid.properties");
pro.load(is);
//2.初始化連接池對象
ds = DruidDataSourceFactory.createDataSource(pro);
} catch (IOException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 獲取連接池對象
*/
public static DataSource getDataSource(){
return ds;
}
/**
* 獲取連接Connection對象
*/
public static Connection getConnection() throws SQLException {
return ds.getConnection();
}
}
druid.properties配置文件定義
遇到問題彙總
1 點擊label標籤有自動聚焦的功能
2 Bootstrap中文文檔，組件之分頁
https://v3.bootcss.com/components/#pagination
3 a標籤使用js函數方法
https://blog.csdn.net/qq_23994787/article/details/77480049
另外input標籤的點擊事件也可以觸發js函數
4 驗證碼校驗的過程是，在後端的checkservlet中，編寫生成驗證碼，並存入服務器的session，然後前端註冊頁面輸入驗證碼之後點擊註冊，將前端傳過來的驗證碼與session進行對比，校驗即可
5 JAVA中request.getParameterMap()用法筆記
一個獲取提交表單數據的新方法request.getParameterMap。
https://blog.csdn.net/lncsdn_123/article/details/78500328
6 foreach循環中的user對象，如果要到其他地方使用，可在js函數中進行傳參
7 Confirm是js裏面的警告函數，可以在前端彈出警告提示框
8 組件選中問題，在組件內編寫點擊事件函數，用this來代指id爲“firstCb”的組件
9 前端的表單用submit方法提交，會把選中組件的id的值一併通過請求參數提交到後端