package?servlet;
import?java.io.IOException;
import?java.sql.Connection;
import?java.sql.DriverManager;
import?java.sql.PreparedStatement;
import?java.sql.ResultSet;
import?java.sql.SQLException;
import?java.util.ArrayList;
import?java.util.List;
import?javax.servlet.ServletException;
import?javax.servlet.http.HttpServlet;
import?javax.servlet.http.HttpServletRequest;
import?javax.servlet.http.HttpServletResponse;
import?bean.Message;
/**
?*?@author?570
?*
?*/
public?class?ListServlet?extends?HttpServlet?{
????/**
?????*?
?????*/
????private?static?final?long?serialVersionUID?=?1L;
????@Override
????protected?void?doGet(HttpServletRequest?req,?HttpServletResponse?resp)?throws?ServletException,?IOException?{??????
????????try?{??????????
????????????String?command?=?req.getParameter("command");//從頁面拿到參數(shù)
????????????String?description?=req.getParameter("description");???
????????????Class.forName("com.mysql.jdbc.Driver");
????????????Connection?conn?=?DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb?characterEncoding=utf8&useSSL=true","root","root");
????????????//String?sql?="SELECT?ID,COMMAND,DESCRIPTION,CONTENT?FROM?imooc_mybatis_list";??????????
????????????//where?1=1?用于語句拼接。。不明所以
????????????StringBuilder?sql?=?new?StringBuilder("select?ID,COMMAND,DESCRIPTION,CONTENT?from?imooc_mybatis_list?where?1=1");?????????
????????????PreparedStatement?ps?=?conn.prepareStatement(sql.toString());???????
????????????//多條件查詢時(shí)，利用List做緩沖，保存查詢參數(shù)，然后再循環(huán)賦值
????????????List<String>?paramer?=?new?ArrayList<String>();
????????????//語句拼接如果查詢的指令非空且非空字符串則執(zhí)行語句拼接查詢
????????????if?(command!=null&&!"".equals(command.trim()))?{
????????????????sql.append("and?COMMAND=?");
????????????????paramer.add(command);
????????????}????????????
????????????if?(description!=null&&!"".equals(description.trim()))?{
????????????????sql.append("and?DESCRIPTION?like?'%'???'%'");
????????????????paramer.add(description);
????????????}
????????????//把頁面上的語句拿給要送到數(shù)據(jù)庫查詢的ps中
????????????for?(int?i?=?0;?i?<?paramer.size();?i++)?{
????????????????ps.setString(i+1,?paramer.get(i));
????????????}
????????????
????????????ResultSet?rs?=?ps.executeQuery();
????????????List<Message>?messageList?=?new?ArrayList<Message>();???????????
????????????while?(rs.next())?{
????????????????Message?message?=?new?Message();
????????????????messageList.add(message);
????????????????message.setId(rs.getString("ID"));
????????????????message.setCommand(rs.getString("COMMADN"));
????????????????message.setDescription(rs.getString("DESCRIPTION"));
????????????????message.setContent(rs.getString("CONTENT"));????????????????
????????????}?????????
????????????req.setAttribute("messageList",?messageList);???????????
????????}?catch?(ClassNotFoundException?e)?{????????????
????????????e.printStackTrace();
????????}?catch?(SQLException?e)?{????????????
????????????e.printStackTrace();
????????}????????
????????req.getRequestDispatcher("/WEB-INF/jsp/list.jsp").forward(req,?resp);
????}??
????@Override
????protected?void?doPost(HttpServletRequest?req,?HttpServletResponse?resp)?throws?ServletException,?IOException?{????????
????????this.doGet(req,?resp);
????}???
}<%@?page?language="java"?contentType="text/html;?charset=UTF-8"?pageEncoding="UTF-8"%>
<%
String?path?=?request.getContextPath();
String?basePath?=?request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<%@?taglib?uri="http://java.sun.com/jsp/jstl/core"?prefix="c"?%>
<!DOCTYPE?html?PUBLIC?"-//W3C//DTD?XHTML?1.0?Transitional//EN"?"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html?xmlns="http://www.w3.org/1999/xhtml">
????<head>
????????<meta?http-equiv="Content-Type"?content="text/html;?charset=UTF-8"?/>
????????<meta?http-equiv="X-UA-Compatible"content="IE=9;?IE=8;?IE=7;?IE=EDGE"?/>
????????<title>內(nèi)容列表頁面</title>
????????<link?href=?"<%=basePath?%>resource/css/all.css"?rel="stylesheet"?type="text/css"?/>
????</head>
????<body?style="background:?#e1e9eb;">
????????<form?action="<%=basePath?%>list"?id="mainForm"?method="post">
????????????<div?class="right">
????????????????<div?class="current">當(dāng)前位置：<a?href="javascript:void(0)"?style="color:#6E6E6E;">內(nèi)容管理</a>?>?內(nèi)容列表</div>
????????????????<div?class="rightCont">
????????????????????<p?class="g_title?fix">內(nèi)容列表?<a?class="btn03"?href="#">新?增</a> <a?class="btn03"?href="#">刪?除</a></p>
????????????????????<table?class="tab1">
????????????????????????<tbody>
????????????????????????????<tr>
????????????????????????????????<td??width="90"?align="right">查詢指令</td>
????????????????????????????????<td>
????????????????????????????????????<input?name="command"?type="text"?class="allInput"?value=""/>
????????????????????????????????</td>
????????????????????????????????<td??width="90"?align="right">描述</td>
????????????????????????????????<td>
????????????????????????????????????<input?name="description"?type="text"?class="allInput"?value=""/>
????????????????????????????????</td>
????????????????????????????????<td?width="85"?align="right"><input?type="submit"?class="tabSub"?value="查?詢"?/></td>
???????????????????????????????</tr>
????????????????????????</tbody>
????????????????????</table>
????????????????????<div?class="zixun?fix">
????????????????????????<table?class="tab2"?width="100%">
????????????????????????????<tbody>
????????????????????????????????<tr>
????????????????????????????????????<th><input?type="checkbox"?id="all"?onclick="#"/></th>
????????????????????????????????????<th>序號</th>
????????????????????????????????????<th>指令名稱</th>
????????????????????????????????????<th>描述</th>
????????????????????????????????????<th>操作</th>
????????????????????????????????</tr>
????????????????????????????????<c:forEach?items="${messageList}"?var="message"?varStatus="status">
????????????????????????????????????<tr?<c:if?test="${status.index%2!=0}">?style="background-color:#ECF6EE;"</c:if>>
????????????????????????????????????<td><input?type="checkbox"?/></td>
????????????????????????????????????<td>${status.index+1}</td>
????????????????????????????????????<td>${message.command}</td>
????????????????????????????????????<td>${message.description}</td>
????????????????????????????????????<td>${message.content}</td>
????????????????????????????????????<td>
????????????????????????????????????????<a?href="#">修改</a>
????????????????????????????????????????<a?href="#">刪除</a>
????????????????????????????????????</td>
????????????????????????????????</tr>
????????????????????????????????</c:forEach>
????????????????????????????</tbody>
????????????????????????</table>
2016-10-23
第一張圖第五十二行錯(cuò)了
sql語法拼寫錯(cuò)誤，前段時(shí)間也遇到了，不過解決了
if (description!=null&&!"".equals(description.trim())) {
? ? ? ? ? ? sql.append("and DESCRIPTION like ?? ");
? ? ? ? ? ? paramer.add("%"+description+"%");
? ? ? ? }
2016-09-16
是不是數(shù)據(jù)庫名稱錯(cuò)誤。
2016-09-08
這個(gè)問題出現(xiàn)有兩天了，我一直沒解決就把課程往下聽了，其中有幾行詩下面課中的代碼。不過自己感覺應(yīng)該不影響頁面顯示列表的問題。另外我的數(shù)據(jù)表中是有值的。。不清楚哪里出了問題，還請大神們不吝解答
2016-09-08
由于不能超過20000字我把jsp中后面的標(biāo)簽刪了。。本身jsp頁面編譯器不現(xiàn)實(shí)錯(cuò)誤