jdbc03 使用servlet实现 / 憋错料

<%@page import="cn.bdqn.bean.News"%>
<%@page import="cn.bdqn.service.impl.NewsServiceImpl"%>
<%@page import="cn.bdqn.service.NewsService"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme() + "://"
            + request.getServerName() + ":" + request.getServerPort()
            + path + "/";
%>
<%-- 引入需要的jstl标签库--%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!DOCTYPE HTML>
<html>
<head>
<base href="<%=basePath%>">

<title>My JSP ‘index.jsp‘ starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<style type="text/css">
<%--
表格中的数据 居中显示          --%> td {
    text-align: center;
}
</style>
</head>
<%-- 需要引入了 外部javaBean  --%>
<jsp:useBean id="service" class="cn.bdqn.service.impl.NewsServiceImpl" />
<jsp:useBean id="pageUtil" class="cn.bdqn.util.PageUtil" />
<body>
  <form action="newsList.jsp" method="get">
    <h1>显示新闻信息</h1>
    <table border="1">
        <tr>
            <td>新闻编号</td>
            <td>新闻标题</td>
            <td>新闻作者</td>
            <td>创建时间</td>
            <td>操作</td>
        </tr>

        <%
            //获取分页的四要素
            int pageSize = 3; //页大小
            int pageIndex = 1; //当前页面
            String num = request.getParameter("pageIndex");//获取pageIndex
            if (num != null && num != "") { //因为第一次打开页面的时候 请求中 压根没有  pageIndex的属性
                pageIndex = Integer.parseInt(num);
            } else {
                pageIndex = 1;
            }
            //给通用的工具类 赋值
            pageUtil.setPageIndex(pageIndex);
            pageUtil.setPageSize(pageSize);
            pageUtil.setTotalCountSize(service.getTotalCountSize()); //总记录数
            pageUtil.getTotalPageCount(); //获取总页数

            List<News> news = service.getNewsByPageList(pageIndex, pageSize);
            //把响应的数据放入作用域
            request.setAttribute("news", news);
            request.setAttribute("pageUtil", pageUtil);
        %>
        <c:forEach items="${news}" var="n" varStatus="s">
            <c:if test="${s.count%2==0}">
                <tr bgcolor="green">
            </c:if>
            <c:if test="${s.count%2!=0}">
                <tr bgcolor="pink">
            </c:if>
            <td>${n.getId()}</td>
            <td>${n.getTitle()}</td>
            <td>${n.getAuthor()}</td>
            <td>${n.getCreateDate()}</td>
            <td><a href="update.jsp?id=${n.getId()}">修改</a>
            </td>
            </tr>
        </c:forEach>

        <tr>
            <td>当前页：${pageUtil.getPageIndex()}</td>
            <td>总页数：${pageUtil.getTotalPageCount()}</td>
            <td>总记录数${pageUtil.getTotalCountSize()}</td>
        </tr>

<%--   引入需要的分页界面   --%>
<c:import url="page.jsp">
    <c:param name="pageIndex" value="${pageUtil.pageIndex}"></c:param>
    <c:param name="totalPageCount" value="${pageUtil.totalPageCount}"></c:param>
</c:import>
    </table>

    </form>
</body>
</html>

修改后的newsList.jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<%-- 引入需要的jstl标签库--%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">

    <title>My JSP ‘page.jsp‘ starting page</title>

    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
<script type="text/javascript">
 function  page(form,num){
     //把传递来的num赋值给当前的页码
     form.pageIndex.value=num;
     form.submit();
 }

</script>

  </head>

  <body>

<%--  表单隐藏域  保存 当前页--%>
  <input type="hidden" name="pageIndex">
<%--javaScript:伪协议 ！  不会跳转界面，只是让我们通过这个连接直接调用JavaScript代码  --%>
        <tr>
            <c:if test="${param.pageIndex>1}">
                <td><a href="javaScript:page(document.forms[0],1)">首页</a></td>
                <td><a href="javaScript:page(document.forms[0],${param.pageIndex-1})">上一页</a></td>
            </c:if>
            <%--    如果当前页码小于总页数    --%>
            <c:if test="${param.pageIndex <param.totalPageCount}">
                <td><a href="javaScript:page(document.forms[0],${param.pageIndex+1})">下一页</a>
                </td>
                <td><a href="javaScript:page(document.forms[0],${param.totalPageCount})">最后一页</a>
                </td>
            </c:if>
            <td><a href="addNews.jsp">新增</a></td>
        </tr>

  </body>
</html>

公用的page.jsp

================使用servlet==========================

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">

    <title>新闻信息的登录界面</title>

    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->

  </head>

  <body>
   <h1>登录界面</h1>
<%--  action="Login"    Login必须在web.xml中又对应的url-pattern --%>
     <form action="Login"  method="post">
         <table>
             <tr>
               <td>用户名：</td>
               <td><input  type="text" name="userName"/></td>
             </tr>
             <tr>
               <td>密码：</td>
               <td><input  type="password" name="password"/></td>
             </tr>
             <tr>
               <td></td>
               <td><input  type="submit" value="登录"/></td>
             </tr>
         </table>
     </form>
  </body>
</html>

修改login.jsp的action

public class LoginServlet extends HttpServlet { //处理登录请求的servlet

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
     doPost(request, response);  //交给 doPost（）处理请求
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
          System.out.println("进入了 LoginServlet");
          request.setCharacterEncoding("utf-8");
           //01.获取用户信息
         String  userName= request.getParameter("userName");
         String  password= request.getParameter("password");
         User user=new User();  //把信息保存在 user中
         user.setPassword(password);
         user.setUserName(userName);
           //02.从数据库取值
         UserService service=new UserServiceImpl();
          boolean  flag= service.login(user);
           if(flag){
               //重定向到 新闻列表servlet   如果直接到新闻界面  是没有值的！
               response.sendRedirect("NewsListServlet");
           }else{
               //重定向到 新闻登录界面
               response.sendRedirect("login.jsp");
           }
    }

}

创建LoginServlet

newsList.jsp修改后的代码

<%@page import="cn.bdqn.bean.News"%>
<%@page import="cn.bdqn.service.impl.NewsServiceImpl"%>
<%@page import="cn.bdqn.service.NewsService"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme() + "://"
            + request.getServerName() + ":" + request.getServerPort()
            + path + "/";
%>
<%-- 引入需要的jstl标签库--%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!DOCTYPE HTML>
<html>
<head>
<base href="<%=basePath%>">

<title>My JSP ‘index.jsp‘ starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<style type="text/css">
<%--
表格中的数据 居中显示          --%> td {
    text-align: center;
}
</style>
</head>
<body>
  <form action="NewsListServlet" method="get">
    <h1>显示新闻信息</h1>
    <table border="1">
        <tr>
            <td>新闻编号</td>
            <td>新闻标题</td>
            <td>新闻作者</td>
            <td>创建时间</td>
            <td>操作</td>
        </tr>

        <c:forEach items="${news}" var="n" varStatus="s">
            <c:if test="${s.count%2==0}">
                <tr bgcolor="green">
            </c:if>
            <c:if test="${s.count%2!=0}">
                <tr bgcolor="pink">
            </c:if>
            <td>${n.getId()}</td>
            <td>${n.getTitle()}</td>
            <td>${n.getAuthor()}</td>
            <td>${n.getCreateDate()}</td>
            <td><a href="update.jsp?id=${n.getId()}">修改</a>
            </td>
            </tr>
        </c:forEach>

        <tr>
            <td>当前页：${pageUtil.getPageIndex()}</td>
            <td>总页数：${pageUtil.getTotalPageCount()}</td>
            <td>总记录数${pageUtil.getTotalCountSize()}</td>
        </tr>

<%--   引入需要的分页界面   --%>
<c:import url="page.jsp">
    <c:param name="pageIndex" value="${pageUtil.pageIndex}"></c:param>
    <c:param name="totalPageCount" value="${pageUtil.totalPageCount}"></c:param>
</c:import>
    </table>

    </form>
</body>
</html>

把newsList.jsp中的java代码提取到NewsListServlet中

public class NewsListServlet extends HttpServlet {

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

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        System.out.println("进入了 NewsListServlet");
        PageUtil pageUtil=new PageUtil();
        NewsService service =new NewsServiceImpl();
        //获取分页的四要素
        int pageSize = 3; //页大小
        int pageIndex = 1; //当前页面
        String num = request.getParameter("pageIndex");//获取pageIndex
        if (num != null && num != "") { //因为第一次打开页面的时候 请求中 压根没有  pageIndex的属性
            pageIndex = Integer.parseInt(num);
        } else {
            pageIndex = 1;
        }
        //给通用的工具类 赋值
        pageUtil.setPageIndex(pageIndex);
        pageUtil.setPageSize(pageSize);
        pageUtil.setTotalCountSize(service.getTotalCountSize()); //总记录数
        pageUtil.getTotalPageCount(); //获取总页数

        List<News> news = service.getNewsByPageList(pageIndex, pageSize);
        //把响应的数据放入作用域
        request.setAttribute("news", news);
        request.setAttribute("pageUtil", pageUtil);
        //转发到newsList.jsp界面
        request.getRequestDispatcher("/newsList.jsp").forward(request, response);
    }

}

NewsListServlet代码

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
    xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
    http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
  <servlet>
    <servlet-name>Login</servlet-name>
    <servlet-class>cn.bdqn.servlet.LoginServlet</servlet-class>
  </servlet>
  <servlet>
    <servlet-name>NewsListServlet</servlet-name>
    <servlet-class>cn.bdqn.servlet.NewsListServlet</servlet-class>
  </servlet>

  <servlet-mapping>
    <servlet-name>Login</servlet-name>
    <url-pattern>/Login</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>NewsListServlet</servlet-name>
    <url-pattern>/NewsListServlet</url-pattern>
  </servlet-mapping>    

  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
</web-app>

web.xml文件中的配置

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">

    <title>新闻信息新增界面</title>

    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
<%--  引入我们需要的  富文本 编辑器    --%>
 <script type="text/javascript" src="ckeditor/ckeditor.js"></script>
<style type="text/css">
  div{
  height:900px;
  width:900px;
     margin:auto;
    padding: auto;
  }
</style>
<script type="text/javascript">
<%--验证用户有没有选择 新闻类别 --%>
  function  check(){
      var goryId=  document.getElementById("goryId").value;
      if(goryId==0){
          alert("请选择新闻类别.....");
          return  false;
      }
      return  true;
  }
</script>

</head>
  <body>
  <div>
  <h1>新闻信息新增界面</h1>
<%-- action="NewsAddServlet"   NewsAddServlet是web.xml文件中   url-pattern  --%>
   <form action="NewsAddServlet" enctype="multipart/form-data" method="post" onsubmit="return  check()">
         <table>
             <tr>
               <td>新闻分类：</td>
               <td>
                 <select name="categoryId" id="goryId">
                   <option  value="0">请选择新闻类别</option>
                   <option  value="1">国内</option>
                   <option  value="2">国际</option>
                   <option  value="3">娱乐</option>
                   <option  value="4">军事</option>
                   <option  value="5">财经</option>
                 </select>
               </td>
             </tr>
             <tr>
               <td>新闻标题：</td>
               <td><input  type="text" name="title"/></td>
             </tr>
             <tr>
               <td>新闻作者：</td>
               <td><input  type="text" name="author"/></td>
             </tr>

             <tr>
               <td>新闻摘要：</td>
               <td><input  type="text" name="summary"/></td>
             </tr>
             <tr>
               <td>创建时间：</td>
               <td><input  type="date" name="createDate"/></td>
             </tr>
             <tr>
               <td>选择文件：</td>
               <td><input  type="file" name="picPath"/></td>
             </tr>

              <tr>
               <td>新闻内容：</td>
               <td><textarea class="ckeditor" name="content">

                 </textarea>
               </td>
             </tr>
             <tr>
               <td></td>
               <td><input  type="submit" value="新增"/></td>
             </tr>
         </table>
     </form>
  </div>

  </body>
</html>

修改addNews.jsp的action

public class NewsAddServlet extends HttpServlet { // 新闻的新增

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doPost(request, response); // 默认执行doPost()
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        System.out.println("进入了NewsAddServlet");
        News news = new News();
        NewsService service = new NewsServiceImpl();
        // 解决乱码问题
        request.setCharacterEncoding("utf-8");

        // 01.文件上传到 哪里去？？？ 我们必须指定用户的上传位置
        String uploadFilePath = request.getSession().getServletContext()
                .getRealPath("upload/");
        // 不确定文件是否已经存在
        File file = new File(uploadFilePath);
        if (!file.exists()) {
            // 不存在 创建
            file.mkdirs();
        }
        // 02.判断前台的form表单是否带有文件
        boolean flag = ServletFileUpload.isMultipartContent(request);
        try {
            if (flag) { // 如果是文件上传
                /*
                 * 如果上传的文件比较小，则直接保存在内存中，速度快！ 文件大的时候，以临时文件的形式，保存在电脑的临时文件夹中！
                 * 我们使用FileItemFactory 接口的对应 实现类 来完成 上传操作
                 */
                DiskFileItemFactory factory = new DiskFileItemFactory();
                ServletFileUpload upload = new ServletFileUpload(factory);
                // 能把请求中的所有元素进行获取！ 返回一个FileItem的集合
                List<FileItem> items = upload.parseRequest(request);
                // 获取Iterator迭代器
                Iterator<FileItem> iter = items.iterator();
                // 事先给 没给元素定义一个名称
                String fileName = "";
                while (iter.hasNext()) { // 遍历出每一个元素
                    FileItem item = iter.next();
                    if (item.isFormField()) { // 如果是普通的元素
                        fileName = item.getFieldName(); // 获取普通元素的名称
                        if (fileName.equals("title")) {
                            news.setTitle(item.getString("utf-8"));
                        } else if (fileName.equals("author")) {
                            news.setAuthor(item.getString("utf-8"));
                        } else if (fileName.equals("content")) {
                            news.setContent(item.getString("utf-8"));
                        } else if (fileName.equals("summary")) {
                            news.setSummary(item.getString("utf-8"));
                        } else if (fileName.equals("createDate")) {
                            news.setCreateDate(new SimpleDateFormat(
                                    "yyyy-MM-dd").parse(item.getString("utf-8")));
                        } else if (fileName.equals("categoryId")) {
                            news.setCategoryId(Integer.parseInt(item
                                    .getString("utf-8")));
                        }
                    } else { // 操作上传的文件
                        String fimeName = item.getName(); // 获取上传文件的名称
                        if (fimeName != null && fimeName != "") {
                            File fullFile = new File(fimeName);
                            // 相当于在uploadFilePath 这个文件下面
                            // 创建一个文件fullFile.getName()
                            File saveFile = new File(uploadFilePath,
                                    fullFile.getName());
                            // 写入 真正的上传
                            try {
                                item.write(saveFile);
                            } catch (Exception e) {
                                e.printStackTrace();
                            }
                            news.setPicPath(fullFile.getName()); // 给news的文件路径赋值
                        }
                    }
                }
            }
        } catch (NumberFormatException e) {
            e.printStackTrace();
        } catch (FileUploadException e) {
            e.printStackTrace();
        } catch (ParseException e) {
            e.printStackTrace();
        }
        service.addNews(news); // 调用底层代码 进行新增操作
        // 新增成功了之后 需要返回到新闻列表界面 转发 会引起 表单的重复提交
        // request.getRequestDispatcher("newsList.jsp").forward(request,
        // response);
        // 重定向 NewsListServlet 拿到值 放入作用于中 才能 去newsList.jsp页面
        response.sendRedirect("NewsListServlet");
    }
}

创建NewsAddServlet

=================实现新闻的修改===============================

<%@page import="cn.bdqn.bean.News"%>
<%@page import="cn.bdqn.service.impl.NewsServiceImpl"%>
<%@page import="cn.bdqn.service.NewsService"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme() + "://"
            + request.getServerName() + ":" + request.getServerPort()
            + path + "/";
%>
<%-- 引入需要的jstl标签库--%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!DOCTYPE HTML>
<html>
<head>
<base href="<%=basePath%>">

<title>My JSP ‘index.jsp‘ starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<style type="text/css">
<%--
表格中的数据 居中显示          --%> td {
    text-align: center;
}
</style>
</head>
<body>
  <form action="NewsListServlet" method="get">
    <h1>显示新闻信息</h1>
    <table border="1">
        <tr>
            <td>新闻编号</td>
            <td>新闻标题</td>
            <td>新闻作者</td>
            <td>创建时间</td>
            <td>操作</td>
        </tr>

        <c:forEach items="${news}" var="n" varStatus="s">
            <c:if test="${s.count%2==0}">
                <tr bgcolor="green">
            </c:if>
            <c:if test="${s.count%2!=0}">
                <tr bgcolor="pink">
            </c:if>
            <td>${n.getId()}</td>
            <td>${n.getTitle()}</td>
            <td>${n.getAuthor()}</td>
            <td>${n.getCreateDate()}</td>
            <td><a href="FindNewsServlet?id=${n.getId()}">修改</a>
            <a href="NewsDelServlet?id=${n.getId()}">删除</a>
            </td>
            </tr>
        </c:forEach>

        <tr>
            <td>当前页：${pageUtil.getPageIndex()}</td>
            <td>总页数：${pageUtil.getTotalPageCount()}</td>
            <td>总记录数${pageUtil.getTotalCountSize()}</td>
        </tr>

<%--   引入需要的分页界面   --%>
<c:import url="page.jsp">
    <c:param name="pageIndex" value="${pageUtil.pageIndex}"></c:param>
    <c:param name="totalPageCount" value="${pageUtil.totalPageCount}"></c:param>
</c:import>
    </table>

    </form>
</body>
</html>

修改后的newsList界面

public class FindNewsServlet extends HttpServlet { // 根据id查询到指定的新闻

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doPost(request, response); // doPost()
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        NewsService service = new NewsServiceImpl();
        News news = service.findById(request.getParameter("id"));
        // 放入作用域
        request.setAttribute("news", news);
        // 转发到update.jsp页面
        request.getRequestDispatcher("/update.jsp").forward(request, response);
    }

}

点击修改按钮后进入的FindNewsServlet

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<%-- 引入需要的jstl标签库--%>
<%@ taglib prefix="f" uri="http://java.sun.com/jsp/jstl/fmt" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">

    <title>新闻信息修改界面</title>

    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->
<%--  引入我们需要的  富文本 编辑器    --%>
 <script type="text/javascript" src="ckeditor/ckeditor.js"></script>
  </head>

  <body>
  <h1>新闻信息修改界面</h1>
   <form action="NewsUpdateServlet" enctype="multipart/form-data" method="post" onsubmit="return  check()">
         <table>
             <tr>
               <td>新闻分类：</td>
               <td>
                 <select name="categoryId" id="goryId">
                   <option  value="0">请选择新闻类别</option>
<%--     下拉框内容的回显              --%>
                   <option <c:if test="${news.categoryId==1}">selected</c:if> value="1">国内</option>
                   <option <c:if test="${news.categoryId==2}">selected</c:if> value="2">国际</option>
                   <option <c:if test="${news.categoryId==3}">selected</c:if> value="3">娱乐</option>
                   <option <c:if test="${news.categoryId==4}">selected</c:if> value="4">军事</option>
                   <option <c:if test="${news.categoryId==5}">selected</c:if>value="5">财经</option>
                 </select>
               </td>
             </tr>
             <tr>
<%--     页可以使用表单的隐藏域         --%>
               <td>新闻编号：</td>
               <td><input  type="text" value="${news.id}" name="id" readonly="readonly"/></td>
             </tr>
             <tr>
               <td>新闻标题：</td>
               <td><input  type="text" value="${news.title}" name="title"/></td>
             </tr>
             <tr>
               <td>新闻作者：</td>
               <td><input  type="text" value="${news.author}" name="author"/></td>
             </tr>

             <tr>
               <td>新闻摘要：</td>
               <td><input  type="text" value="${news.summary}" name="summary"/></td>
             </tr>
             <tr>
               <td>创建时间：</td>
               <td><input  type="text" value="<f:formatDate value=‘${news.createDate}‘ pattern=‘yyyy-MM-dd‘/>" name="createDate"/>

               </td>
             </tr>
             <tr>
               <td>选择文件：</td>
               <td><input  type="file"  name="picPath"/></td>
             </tr>

              <tr>
               <td>新闻内容：</td>
               <td><textarea class="ckeditor" name="content">
                   ${news.content}
                 </textarea>
               </td>
             </tr>
             <tr>
               <td></td>
               <td><input  type="submit" value="修改"/></td>
             </tr>
         </table>
     </form>
  </div>
  </body>
</html>

修改后的update.jsp页面

public class NewsUpdateServlet extends HttpServlet { // 修改新闻

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doPost(request, response); // doPost()
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        System.out.println("进入了NewsUpdateServlet");
        News news = new News();
        NewsService service = new NewsServiceImpl();
        // 解决乱码问题
        request.setCharacterEncoding("utf-8");
        // 01.文件上传到 哪里去？？？ 我们必须指定用户的上传位置
        String uploadFilePath = request.getSession().getServletContext()
                .getRealPath("upload/");
        // 不确定文件是否已经存在
        File file = new File(uploadFilePath);
        if (!file.exists()) {
            // 不存在 创建
            file.mkdirs();
        }
        // 02.判断前台的form表单是否带有文件
        boolean flag = ServletFileUpload.isMultipartContent(request);
        try {
            if (flag) { // 如果是文件上传
                /*
                 * 如果上传的文件比较小，则直接保存在内存中，速度快！ 文件大的时候，以临时文件的形式，保存在电脑的临时文件夹中！
                 * 我们使用FileItemFactory 接口的对应 实现类 来完成 上传操作
                 */
                DiskFileItemFactory factory = new DiskFileItemFactory();
                ServletFileUpload upload = new ServletFileUpload(factory);
                // 能把请求中的所有元素进行获取！ 返回一个FileItem的集合
                List<FileItem> items = upload.parseRequest(request);
                // 获取Iterator迭代器
                Iterator<FileItem> iter = items.iterator();
                // 事先给 没给元素定义一个名称
                String fileName = "";
                while (iter.hasNext()) { // 遍历出每一个元素
                    FileItem item = iter.next();
                    if (item.isFormField()) { // 如果是普通的元素
                        fileName = item.getFieldName(); // 获取普通元素的名称
                        if (fileName.equals("title")) {
                            news.setTitle(item.getString("utf-8"));
                        } else if (fileName.equals("author")) {
                            news.setAuthor(item.getString("utf-8"));
                        } else if (fileName.equals("content")) {
                            news.setContent(item.getString("utf-8"));
                        } else if (fileName.equals("summary")) {
                            news.setSummary(item.getString("utf-8"));
                        } else if (fileName.equals("createDate")) {
                            news.setCreateDate(new SimpleDateFormat(
                                    "yyyy-MM-dd").parse(item.getString("utf-8")));
                        } else if (fileName.equals("categoryId")) {
                            news.setCategoryId(Integer.parseInt(item
                                    .getString("utf-8")));
                        } else if (fileName.equals("id")) { // 设置新闻编号
                            news.setId(Integer.parseInt(item.getString("utf-8")));
                        }
                    } else { // 操作上传的文件
                        String fimeName = item.getName(); // 获取上传文件的名称
                        if (fimeName != null && fimeName != "") {
                            File fullFile = new File(fimeName);
                            // 相当于在uploadFilePath 这个文件下面
                            // 创建一个文件fullFile.getName()
                            File saveFile = new File(uploadFilePath,
                                    fullFile.getName());
                            // 写入 真正的上传
                            try {
                                item.write(saveFile);
                            } catch (Exception e) {
                                e.printStackTrace();
                            }
                            news.setPicPath(fullFile.getName()); // 给news的文件路径赋值
                        }
                    }
                }
            }
        } catch (NumberFormatException e) {
            e.printStackTrace();
        } catch (FileUploadException e) {
            e.printStackTrace();
        } catch (ParseException e) {
            e.printStackTrace();
        }
        service.updateNews(news); // 调用底层代码 进行修改操作
        // 重定向 NewsListServlet 拿到值 放入作用于中 才能 去newsList.jsp页面
        response.sendRedirect("NewsListServlet");
    }
}

点击修改后提交到的NewsUpdateServlet

 // 修改新闻
    public int updateNews(News news) {
        getConnection();
        // 之前 只是修改了 新闻标题 现在 全部都修改了
        String sql = "update  news_detail set  categoryId=?,title=?,content=?,author=?,summary=?,createDate=?"
                + " where id=?";
        Object[] params = { news.getCategoryId(), news.getTitle(),
                news.getContent(), news.getAuthor(), news.getSummary(),
                news.getCreateDate(), news.getId() };
        int num = executeUpdate(sql, params);
        return num;
    }

修改NewsDaoImpl中的修改方法

=================实现新闻的删除===============================

public class NewsDelServlet extends HttpServlet { // 删除指定的新闻

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doPost(request, response); // 默认执行doPost()
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        System.out.println("进入了NewsDelServlet ");
        NewsService service = new NewsServiceImpl();
        // 获取传递过来的id
        String id = request.getParameter("id");
        News news = service.findById(id);
        System.out.println(news); // 测试 查看news信息
        service.deleteNews(news); // 删除
        // 重定向到 新闻处理servlet
        response.sendRedirect("NewsListServlet");
    }

}

点击删除按钮后的NewsDelServlet

================验证用户登录后才能进入新闻详情界面=========================

public class LoginServlet extends HttpServlet { // 处理登录请求的servlet

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doPost(request, response); // 交给 doPost（）处理请求
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        System.out.println("进入了 LoginServlet");
        // 01.获取用户信息
        String userName = request.getParameter("userName");
        String password = request.getParameter("password");
        User user = new User(); // 把信息保存在 user中
        user.setPassword(password);
        user.setUserName(userName);
        // 02.从数据库取值
        UserService service = new UserServiceImpl();
        boolean flag = service.login(user);
        if (flag) {
            // 把用户信息放入 作用域 过滤器中需要判断
            request.getSession().setAttribute("user", user);
            // 重定向到 新闻列表servlet 如果直接到新闻界面 是没有值的！
            response.sendRedirect("NewsListServlet");
        } else {
            // 重定向到 新闻登录界面
            response.sendRedirect("login.jsp");
        }
    }

}

修改后的LoginServlet

public class LoginFilter implements Filter {

    public void destroy() {
        System.out.println("LoginFilter在服务器关闭的时候 执行一次 销毁......");
    }

    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) throws IOException, ServletException {
        request.setCharacterEncoding("utf-8"); // 给所有的servlet设置编码格式

        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        HttpServletResponse httpServletResponse = (HttpServletResponse) response;
        // 获取session中的用户
        User user = (User) httpServletRequest.getSession().getAttribute("user");
        // 获取用户请求的路径
        String path = httpServletRequest.getRequestURI();
        /**
         * 判断用户url
         * 我们的登录界面login.jsp  是不能拦截的
         * 用户已经登录了               是不能拦截的
         */
        if (path.indexOf("login") > -1 || (user != null)) {
            chain.doFilter(request, response);
        } else {
            httpServletResponse.sendRedirect("login.jsp");
        }

    }

    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("LoginFilter在服务器启动的时候 执行一次 初始化......");
    }

}

创建对应的LoginFilter过滤器

把login.jsp页面中的form表单 action改成login! 同样的在web.xml中的LoginServlet对应的mapping url 页要改成 /login

 <!--
  web.xml文件 加载的顺序
   01. context-param  :所有servlet共享
   02.listener
   03.filter   如果有多个   按照  filterClass 加载的顺序
   04.servlet

   filter 可以配置很多！
       真正执行的顺序是什么？  按照filter-Mapping的顺序  执行！

  load-on-startup:
  值没有设置，或者为负数的时候，都是在用户访问的时候 执行初始化操作！
  值为0或者大于0时，都是在服务器启动的时候初始化！ 值越小 初始化越早！
    -->

/**
 * 使用注解可以替换 web.xml文件中的配置
 *
 * 环境必须是java ee6版本
 * value="/LoginServlet"  必须加上/
 * urlPatterns={"/LoginServlet","login"}
 * value和urlPatterns 不能同时存在
 *
 * 如果只有一个value属性可以省略
 * 比如@WebServlet("/LoginServlet") 也是正确的！
 * 等同于@WebServlet(value="/LoginServlet")
 */
@WebServlet("/LoginServlet")
public class LoginServlet extends HttpServlet

//多个初始化参数的配置
@WebServlet(value="/LoginServlet",initParams={@WebInitParam(name="name",value="小黑"),
        @WebInitParam(name="age",value="50")})
public class LoginServlet extends HttpServlet {

时间： 2024-11-09 00:32:59

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