从零开始，编写简单的课程信息管理系统（使用jsp+servlet+javabean架构）
一、相关的软件下载和环境配置
1、下载并配置JDK。
2、下载eclipse。
3、下载并配置apache-tomcat（服务器）。
4、下载MySQL（数据库）。
5、下载Navicat for MySQL（数据库可视化工具），方便对数据库的操作。
6、下载jdbc用来实现eclipse中的项目与数据库实现连接。
---以上可在网上查询教程
二、实现简单的课程信息管理系统
1、
打开eclipse，点击File—》New—》other—》Dynamic Web Project
（若你的eclipse中找不到或者没有Dynamic Web Project，可上网搜素解决办法）
点击后会出现如下窗口
需要填写Project name，可随意填写（最好是英文的），其他不需填写，填写完毕之后点击Finish
2、
项目建立完之后，eclipse左侧的Project Explorer会出现你建立的项目，如下图
3、
在我的电脑中，打开你下载的jdbc（也就是mysql-connector-java-8.0.13）所在的文件夹，如下图
将mysql-connector-java-8.0.13文件复制
粘贴在eclipse中，你所建立的项目下的 WebContent/WEB-INF/lib 文件夹下，如下图
然后，在你刚刚粘贴的文件上右击，Build Path—》Add to Build Path，如下图
这样就完成了jdbc的导入
4、
在 WebContent 文件夹下，新建如下图中的JSP文件，Login.jsp和signinerror.jsp是用来登陆的，这里不必建立。
4（1）head.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title></title> <style type="text/css"> .headdiv{ background-color:#3F51B5; width:100%; height:130px; } .headdiv P{ font-family:YouYuan; font-size:20px; color:#E8EAF6; position:relative; left:20px; top:45px; } </style> </head> <body> <div class="headdiv"> <p>ec-web课程信息综合管理平台</p> </div> </body> </html>
4（2）left.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title></title> <style type="text/css"> .leftMenu{ background-color:#7986CB; width:250px; height:600px; position:relative; top:0px; } .menuParent{ background-color:#BBDEFB; } </style> </head> <body> <div class="leftMenu"> <div class="menu"> <div class="menuParent"> <div class="ListTitlePanel"> <div class="ListTitle"> <strong>课程信息管理</strong> <div class="leftbgbt"></div> </div> </div> <div class="menuList"> <div><a target="mainAction" href="USEJSP/add.jsp">课程信息录入</a></div> <div><a target="mainAction" href="USEJSP/update.jsp">课程信息修改</a></div> <div><a target="mainAction" href="USEJSP/delete.jsp">删除课程信息</a></div> <div><a target="mainAction" href="USEJSP/search.jsp">查询课程信息</a></div> </div> </div> </div> </div> <script type="text/javascript"> </script> </body> </html>
4（3）index.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title></title> </head> <body> 这是小主页 </body> </html>
4（4）main.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>课程信息管理系统</title> <style type="text/css"> .headframe{ width:100%; height:130px; border:0; } .leftframe{ float:left; width:250px; height:600px; border:0; } .mainframe{ float:right; width:1200px; height:600px; border:0; } </style> </head> <iframe src="head.jsp" class="headframe" scrolling="no"></iframe> <iframe src="left.jsp" class="leftframe" scrolling="no"></iframe> <iframe src="index.jsp" name="mainAction" class="mainframe"></iframe> </html>
5、
在WebContent文件夹下建立名为USEJSP的文件夹，在USEJSP文件夹下，建立如下图的JSP文件
5（1）add.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title></title> <style type="text/css"> .butn{ display:inline-block; padding: 8px 35px; background-color:#32CD32; color:white; border:none; text-align:center; text-decoration:none; border-radius:5px; position:absolute; left:40px; top:95px; } </style> </head> <body> <div class="container"> <section> <form action="${pageContext.request.contextPath}/AddServlet/AddCurrServlet?method=add" method="post" onsubmit="return check()"> <!---${pageContext.request.contextPath}的目的是找到主工程的名字，/Servlet/Userservlet就是web.xml下面配置的路径，也就是servlet的路径---> <span class="cname">课程名称</span> <input type="text" name="cname" class="icname" placeholder=" class-name" id="icname"> <br/> <span class="teacher">任课教师</span> <input type="text" name="teacher" class="iteacher" placeholder=" teacher" id="iteacher"> <br/> <span class="place">上课地点</span> <input type="text" name="place" class="iplace" placeholder=" place" id="iplace"> <br/> <input type="submit" value="保 存" class="butn"> <br/> </form> </section> </div> <script type="text/javascript"> function check() { var cname = document.getElementById("icname"); var teacher = document.getElementById("iteacher"); var place = document.getElementById("iplace"); var placestr = place.value.substring(0,2); //非空 if(cname.value == '') { alert('课程名称为空'); cname.focus(); return false; } if(teacher.value == '') { alert('教师为空'); teacher.focus(); return false; } if(place.value == '') { alert('上课地点为空'); place.focus(); return false; } //教师 if(teacher.value != '王建民' && teacher.value != '王辉' && teacher.value != '刘丹' && teacher.value != '刘立嘉' && teacher.value != '杨子光'){ alert('教师名称错误'); return false; } //教室 if(!/^基教/.test(placestr) && !/^一教/.test(placestr) && !/^二教/.test(placestr) && !/^三教/.test(placestr)) { alert('上课地点错误'); return false; } return true; } </script> </body> </html>
5（2）addnameerror.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title></title> <style type="text/css"> .butn{ display:inline-block; padding: 8px 35px; background-color:#32CD32; color:white; border:none; text-align:center; text-decoration:none; border-radius:5px; position:absolute; left:40px; top:95px; } </style> </head> <body onload="alt()"> <div class="container"> <section> <form action="${pageContext.request.contextPath}/AddServlet/AddCurrServlet?method=add" method="post" onsubmit="return check()"> <!---${pageContext.request.contextPath}的目的是找到主工程的名字，/Servlet/Userservlet就是web.xml下面配置的路径，也就是servlet的路径---> <span class="cname">课程名称</span> <input type="text" name="cname" class="icname" placeholder=" class-name" id="icname"> <br/> <span class="teacher">任课教师</span> <input type="text" name="teacher" class="iteacher" placeholder=" teacher" id="iteacher"> <br/> <span class="place">上课地点</span> <input type="text" name="place" class="iplace" placeholder=" place" id="iplace"> <br/> <input type="submit" value="保 存" class="butn"> <br/> </form> </section> </div> <script type="text/javascript"> function check() { var cname = document.getElementById("icname"); var teacher = document.getElementById("iteacher"); var place = document.getElementById("iplace"); var placestr = place.value.substring(0,2); //非空 if(cname.value == '') { alert('课程名称为空'); cname.focus(); return false; } if(teacher.value == '') { alert('教师为空'); teacher.focus(); return false; } if(place.value == '') { alert('上课地点为空'); place.focus(); return false; } //教师 if(teacher.value != '王建民' && teacher.value != '王辉' && teacher.value != '刘丹' && teacher.value != '刘立嘉' && teacher.value != '杨子光'){ alert('教师名称错误'); return false; } //教室 if(!/^基教/.test(placestr) && !/^一教/.test(placestr) && !/^二教/.test(placestr) && !/^三教/.test(placestr)) { alert('上课地点错误'); return false; } return true; } function alt() { alert('课程名称重复'); } </script> </body> </html>
5（3）delete.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <%@page import="java.sql.*"%> <%@page import="java.sql.Connection"%> <%@page import="java.sql.Statement"%> <%@page import="java.sql.ResultSet"%> <%@page import="java.sql.DriverManager"%> <%@page import="javax.servlet.http.HttpServletRequest"%> <html> <head> <meta charset="UTF-8"> <title></title> <style type="text/css"> .butn{ display:inline-block; padding: 8px 35px; background-color:#32CD32; color:white; border:none; text-align:center; text-decoration:none; border-radius:5px; position:absolute; left:40px; top:95px; } </style> </head> <body> <div> <section> <form action="${pageContext.request.contextPath}/DeleteServlet/DeleteCurrServlet?method=add" method="post" onsubmit="return check()"> <span class="cname">课程名称</span> <input type="text" name="cname" id="icname" class="icname" placeholder=" class-name"> <br/> <input type="submit" value="删除" class="butn"> <br/> </form> </section> </div> <script type="text/javascript"> function check() { var cname = document.getElementById("icname"); //非空 if(cname.value == '') { alert('课程名称为空,请重新输入'); cname.focus(); return false; } return true; } </script> </body> </html>
5（4）search.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <%@page import="java.sql.*"%> <%@page import="java.sql.Connection"%> <%@page import="java.sql.Statement"%> <%@page import="java.sql.ResultSet"%> <%@page import="java.sql.DriverManager"%> <%@page import="javax.servlet.http.HttpServletRequest"%> <html> <head> <meta charset="UTF-8"> <title></title> <style type="text/css"> .butn{ display:inline-block; padding: 8px 35px; background-color:#32CD32; color:white; border:none; text-align:center; text-decoration:none; border-radius:5px; position:absolute; left:40px; top:95px; } </style> </head> <body> <div> <section> <form action="${pageContext.request.contextPath}/SearchServlet/SearchCurrServlet?method=add" method="post"> <span class="cname">课程名称</span> <input type="text" name="cname" id="cname" class="icname" placeholder=" class-name"> <br/> <span class="teacher">任课教师</span> <input type="text" name="teacher" id="teacher" class="iteacher" placeholder=" teacher"> <br/> <span class="place">上课地点</span> <input type="text" name="place" id="place" class="iplace" placeholder=" place"> <br/> <input type="submit" value="查询" class="butn"> <br/> </form> </section> </div> </body> </html>
5（5）update.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <%@page import="java.sql.*"%> <%@page import="java.sql.Connection"%> <%@page import="java.sql.Statement"%> <%@page import="java.sql.ResultSet"%> <%@page import="java.sql.DriverManager"%> <html> <head> <meta charset="UTF-8"> <title></title> </head> <body> <form action="${pageContext.request.contextPath}/UpdateServlet/UpdateCurrServlet?method=update" method="post" onsubmit="return check()"> <span class="cname">需要修改的课程名称</span> <input type="text" name="tempcname" class="itempcname" placeholder=" class-name" id="itempcname"> <br/> <table border="1" bgcolor="#ffffff" align="" cellspacing="1" cellpadding="1"> <caption>输入修改信息</caption> <tr> <td align="center" width=16%>新课程名称</td> <td align="center" width=16%>新任课教师</td> <td align="center" width=25%>新上课地点</td> <td align="center" width=16%>操作</td> </tr> <tr> <td width=16% align="center"><input type="text" name="cname" class="icname" placeholder=" class-name" id="icname"></td> <td width=16% align="center"><input type="text" name="teacher" class="iteacher" placeholder=" teacher" id="iteacher"></td> <td width=25% align="center"><input type="text" name="place" class="iplace" placeholder=" place" id="iplace"></td> <td width=16% align="center"><input type="submit" value="修 改" class="butn"></td> </tr> </table> </form> </body> <script type="text/javascript"> function check() { var ctempname = document.getElementById("itempcname"); var cname = document.getElementById("icname"); var teacher = document.getElementById("iteacher"); var place = document.getElementById("iplace"); var placestr = place.value.substring(0,2); //非空 if(ctempname.value == ''){ alert('需修改课程名称为空'); teacher.focus(); return false; } if(cname.value == '') { alert('课程名称为空'); cname.focus(); return false; } if(teacher.value == '') { alert('教师为空'); teacher.focus(); return false; } if(place.value == '') { alert('上课地点为空'); place.focus(); return false; } //教师 if(teacher.value != '王建民' && teacher.value != '王辉' && teacher.value != '刘丹' && teacher.value != '刘立嘉' && teacher.value != '杨子光'){ alert('教师名称错误'); return false; } //教室 if(!/^基教/.test(placestr) && !/^一教/.test(placestr) && !/^二教/.test(placestr) && !/^三教/.test(placestr)) { alert('上课地点错误'); return false; } return true; } </script> </html>
6、
下面，生成web.xml文件（用来配置跳转路径）
在你的项目上右击，java EE Tool—》Generate Deployment Descriptor Stub
这样，在WebContent/WEB-INF文件夹下就生成了.xml文件，如下图
6（1）Web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0"> <display-name>curriculum_information_management_web</display-name> <welcome-file-list> <welcome-file>index.html</welcome-file> <welcome-file>index.htm</welcome-file> <welcome-file>index.jsp</welcome-file> <welcome-file>default.html</welcome-file> <welcome-file>default.htm</welcome-file> <welcome-file>default.jsp</welcome-file> </welcome-file-list> <servlet> <servlet-name>Userservlet</servlet-name> <!--servlet的别名，随便取 --> <!--servlet的包路径，后面再加上.servlet类名 ，这里的类名必须是包下面的servlet类名，目的是让找到该servlet的路径 --> <servlet-class>com.Servlet.Userservlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>Userservlet</servlet-name> <!--servlet的别名，和上面保持一致就行 --> <!--jsp跳转到servlet的路径名，自己取，用来从jsp界面跳转到servlet的路径，程序会根据路径找到servlet的位置 --> <url-pattern>/Servlet/Userservlet</url-pattern><!-- --> </servlet-mapping> <servlet> <servlet-name>AddCurrServlet</servlet-name> <servlet-class>com.Servlet.AddCurrServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>AddCurrServlet</servlet-name> <url-pattern>/AddServlet/AddCurrServlet</url-pattern><!-- --> </servlet-mapping> <servlet> <servlet-name>SearchCurrServlet</servlet-name> <servlet-class>com.Servlet.SearchCurrServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>SearchCurrServlet</servlet-name> <url-pattern>/SearchServlet/SearchCurrServlet</url-pattern><!-- --> </servlet-mapping> <servlet> <servlet-name>DeleteCurrServlet</servlet-name> <servlet-class>com.Servlet.DeleteCurrServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>DeleteCurrServlet</servlet-name> <url-pattern>/DeleteServlet/DeleteCurrServlet</url-pattern><!-- --> </servlet-mapping> <servlet> <servlet-name>UpdateCurrServlet</servlet-name> <servlet-class>com.Servlet.UpdateCurrServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>UpdateCurrServlet</servlet-name> <url-pattern>/UpdateServlet/UpdateCurrServlet</url-pattern><!-- --> </servlet-mapping> </web-app>
7、
在项目下的 Java Resources/src 建立包，如下图
然后，在各包下建立类，如图
7（1）com.Bean
建立CurrBean.java文件
package com.Bean; public class CurrBean { private String name; private String teacher; private String place; public String getName() { return name; } public void setName(String name) { this.name = name; } public String getTeacher() { return teacher; } public void setTeacher(String teacher) { this.teacher = teacher; } public String getPlace() { return place; } public void setPlace(String place) { this.place = place; } }
7（2）com.Dao（该包中的类是用来登录操作的，在这里只是写出来，不用实现）
建立Userdao.java文件
package com.Dao; import java.sql.Connection; import java.sql.ResultSet; import java.sql.Statement; import com.DBUtil.*; public class Userdao { public int login(String username,String password) { Connection conn = DBUtil.getConn();//这里就是从DBUtil类里面得到连接 Statement state =null; ResultSet rs = null; int flag=0; try { String sql = "select * from admin";//SQL语句 state = conn.createStatement(); rs=state.executeQuery(sql); while(rs.next()) { if(rs.getString("password").equals(password)&&rs.getString("username").equals(username)) { flag=1; } } } catch(Exception e) { e.printStackTrace(); } finally { DBUtil.close(rs, state, conn); } return flag; } }
7（3）com.DBUtil
建立CurrDBUtil.java文件（链接数据库）
package com.DBUtil; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class CurrDBUtil { public static String db_url="jdbc:mysql://localhost:3306/curriculum?useSSL=true&serverTimezone=UTC"; //这是连接数据库，userdome是数据库的名称，userUnicode=true&characterEncoding=UTF-8是将字符集设置为utf-8，避免乱码。 public static String db_user="root";//数据的用户名 public static String db_password="lty";//数据库的密码 public static Connection getConn()//获取连接，返回Connection类型，必须设置为static这样才能在其他类中使用 { Connection conn=null; try { Class.forName("com.mysql.jdbc.Driver");//加载驱动 conn=DriverManager.getConnection(db_url,db_user,db_password);//连接数据库 } catch(Exception e) { e.printStackTrace(); } return conn; } public static void close(Statement state,Connection conn)//关闭函数 { if(state!=null)//只有状态和连接时，先关闭状态 { try { state.close(); } catch(SQLException e) { e.printStackTrace(); } } if(conn!=null) { try { conn.close(); } catch(SQLException e) { e.printStackTrace(); } } } public static void close(ResultSet rs,Statement state,Connection conn) { if(rs!=null)//有结果集，状态和连接时，先关闭结果集，在关闭状态，在关闭连接 { try { rs.close(); } catch(SQLException e) { e.printStackTrace(); } } if(state!=null) { try { state.close(); } catch(SQLException e) { e.printStackTrace(); } } if(conn!=null) { try { conn.close(); } catch(SQLException e) { e.printStackTrace(); } } } }
建立DBUtil.java文件（用来链接登录数据库，不必实现）
package com.DBUtil; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class DBUtil { public static String db_url="jdbc:mysql://localhost:3306/userdome?useSSL=true&serverTimezone=UTC"; //这是连接数据库，userdome是数据库的名称，userUnicode=true&characterEncoding=UTF-8是将字符集设置为utf-8，避免乱码。 public static String db_user="root";//数据的用户名 public static String db_password="lty";//数据库的密码 public static Connection getConn()//获取连接，返回Connection类型，必须设置为static这样才能在其他类中使用 { Connection conn=null; try { Class.forName("com.mysql.jdbc.Driver");//加载驱动 conn=DriverManager.getConnection(db_url,db_user,db_password);//连接数据库 } catch(Exception e) { e.printStackTrace(); } return conn; } public static void close(Statement state,Connection conn)//关闭函数 { if(state!=null)//只有状态和连接时，先关闭状态 { try { state.close(); } catch(SQLException e) { e.printStackTrace(); } } if(conn!=null) { try { conn.close(); } catch(SQLException e) { e.printStackTrace(); } } } public static void close(ResultSet rs,Statement state,Connection conn) { if(rs!=null)//有结果集，状态和连接时，先关闭结果集，在关闭状态，在关闭连接 { try { rs.close(); } catch(SQLException e) { e.printStackTrace(); } } if(state!=null) { try { state.close(); } catch(SQLException e) { e.printStackTrace(); } } if(conn!=null) { try { conn.close(); } catch(SQLException e) { e.printStackTrace(); } } } }
7（4）com.Servlet
AddCurrServlet.java 实现课程的增加
package com.Servlet; import java.io.IOException; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.Bean.CurrBean; import com.DBUtil.*; public class AddCurrServlet extends HttpServlet { private static final long serialVersionUID = 1L; protected void doPost(HttpServletRequest req,HttpServletResponse resp)throws ServletException,IOException{ resp.setContentType("add.jsp"); req.setCharacterEncoding("UTF-8"); String name; String teacher; String place; name = req.getParameter("cname"); teacher = req.getParameter("teacher"); place = req.getParameter("place"); CurrBean currbean = new CurrBean(); currbean.setName(name); currbean.setTeacher(teacher); currbean.setPlace(place); AddCurrInterface addCurrInterface = new AddCurrInterface(); @SuppressWarnings("unused") int temp = 0; try { temp = addCurrInterface.addUser(currbean); if(temp == 1) { resp.sendRedirect(req.getContextPath()+"/index.jsp"); }else if(temp == 2) { resp.sendRedirect(req.getContextPath()+"/USEJSP/addnameerror.jsp"); } } catch (SQLException e) { e.printStackTrace(); } } } class AddCurrInterface extends HttpServlet{ private static final long serialVersionUID = 1L; public int addUser(CurrBean cb) throws SQLException { String name; String teacher; String place; name = cb.getName(); teacher = cb.getTeacher(); place = cb.getPlace(); //连接数据库 Connection conn = CurrDBUtil.getConn(); PreparedStatement pstmt = null; Statement stmt = conn.createStatement(); String selectsql = "select * from curr_info"; ResultSet rs = stmt.executeQuery(selectsql); int tt = 0; while(rs.next()) { if(rs.getString("name").equals(name)) { tt = 2; } } if(tt == 0) { String sql = "insert into curr_info (name,teacher,place) values (?,?,?)";//数据库指令 pstmt = conn.prepareStatement(sql);//发送sql语句 //下面是插入到具体的地方 pstmt.setString(1, name); pstmt.setString(2, teacher); pstmt.setString(3, place); pstmt.executeUpdate(); System.out.println("添加成功！"); return 1; }else if(tt == 2) { return 2; } return 0; } }
DeleteCurrServlet.java 实现课程的删除
package com.Servlet; import java.io.BufferedWriter; import java.io.IOException; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.sql.Connection; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.DBUtil.CurrDBUtil; public class DeleteCurrServlet extends HttpServlet { private static final long serialVersionUID = 1L; protected void doPost(HttpServletRequest req,HttpServletResponse resp)throws ServletException,IOException{ resp.setContentType("delete.jsp"); req.setCharacterEncoding("UTF-8"); String name; @SuppressWarnings("unused") int ii = 0; name = req.getParameter("cname"); //连接数据库 Connection conn = CurrDBUtil.getConn(); try { Statement stmt = conn.createStatement(); String selectsql = "select * from curr_info"; ResultSet rs = stmt.executeQuery(selectsql); while(rs.next()) { if(rs.getString("name").equals(name)) { ii = rs.getInt("id"); //Get output stream and writers OutputStream out=resp.getOutputStream(); PrintWriter pw=new PrintWriter(new BufferedWriter(new OutputStreamWriter(out))); //Print HTML pw.println("<HTML><HEAD><TITLE>输出HTML标签</HEAD></TITLE><BODY>"); pw.println("<table border=\"1\" bgcolor=\"#ffffff\" align=\"\" cellspacing=\"1\" cellpadding=\"1\">"); pw.println("<tr>\r\n" + "<td align=\"center\" width=16%>课程名称</td>\r\n" + "<td align=\"center\" width=16%>任课教师</td>\r\n" + "<td align=\"center\" width=35%>上课地点</td>\r\n" + "</tr>"); pw.println("<tr>\r\n" + "<td width=16% align=\"center\">"+rs.getString("name")+"</td>\r\n" + "<td width=16% align=\"center\">"+rs.getString("teacher")+"</td>\r\n" + "<td width=35% align=\"center\">"+rs.getString("place")+"</td>\r\n" + "</tr>"); pw.println("该课程已删除！"); pw.println("</BODY></HTML>"); pw.flush(); pw.close(); } } String delesql="delete from curr_info where name='"+name+"' ";//生成一条sql语句 stmt.executeUpdate(delesql);//执行sql语句 } catch (SQLException e) { e.printStackTrace(); } } }
SearchCurrServlet.java 实现课程的查询
package com.Servlet; import java.io.BufferedWriter; import java.io.IOException; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.sql.Connection; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.DBUtil.CurrDBUtil; public class SearchCurrServlet extends HttpServlet { private static final long serialVersionUID = 1L; protected void doPost(HttpServletRequest req,HttpServletResponse resp)throws ServletException,IOException{ resp.setContentType("search.jsp"); req.setCharacterEncoding("UTF-8"); String name; String teacher; String place; name = req.getParameter("cname"); teacher = req.getParameter("teacher"); place = req.getParameter("place"); int temp = 0; //连接数据库 Connection conn = CurrDBUtil.getConn(); try { Statement stmt = conn.createStatement(); String selectsql = "select * from curr_info"; ResultSet rs = stmt.executeQuery(selectsql); //Get output stream and writers OutputStream out=resp.getOutputStream(); PrintWriter pw=new PrintWriter(new BufferedWriter(new OutputStreamWriter(out))); //Print HTML pw.println("<HTML><HEAD><TITLE>输出HTML标签</HEAD></TITLE><BODY>"); pw.println("<table border=\"1\" bgcolor=\"#ffffff\" align=\"\" cellspacing=\"1\" cellpadding=\"1\">"); pw.println("<tr>\r\n" + "<td align=\"center\" width=16%>课程名称</td>\r\n" + "<td align=\"center\" width=16%>任课教师</td>\r\n" + "<td align=\"center\" width=35%>上课地点</td>\r\n" + "</tr>"); while(rs.next()) { if(rs.getString("name").equals(name) || rs.getString("teacher").equals(teacher) || rs.getString("place").equals(place)) { pw.println("<tr>\r\n" + "<td width=16% align=\"center\">"+rs.getString("name")+"</td>\r\n" + "<td width=16% align=\"center\">"+rs.getString("teacher")+"</td>\r\n" + "<td width=35% align=\"center\">"+rs.getString("place")+"</td>\r\n" + "</tr>"); temp++; } /* else { //Get output stream and writers OutputStream out=resp.getOutputStream(); PrintWriter pw=new PrintWriter(new BufferedWriter(new OutputStreamWriter(out))); //Print HTML pw.println("<HTML><HEAD><TITLE>输出HTML标签</HEAD></TITLE><BODY>"); pw.println("查询错误！"); pw.println("</BODY></HTML>"); pw.flush(); pw.close(); } */ } if(temp == 0) { pw.println("查询错误！"); } pw.println("</BODY></HTML>"); pw.flush(); pw.close(); } catch (SQLException e) { e.printStackTrace(); } } }
UpdateCurrServlet.java 实现课程的修改
package com.Servlet; import java.io.IOException; import java.sql.Connection; import java.sql.SQLException; import java.sql.Statement; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.DBUtil.CurrDBUtil; public class UpdateCurrServlet extends HttpServlet { private static final long serialVersionUID = 1L; protected void doPost(HttpServletRequest req,HttpServletResponse resp)throws ServletException,IOException{ resp.setContentType("update.jsp"); req.setCharacterEncoding("UTF-8"); String tempname; String name; String teacher; String place; tempname = req.getParameter("tempcname"); name = req.getParameter("cname"); teacher = req.getParameter("teacher"); place = req.getParameter("place"); //连接数据库 Connection conn = CurrDBUtil.getConn(); try { Statement stmt = conn.createStatement(); String updatesql = "update curr_info set name='"+name+"',teacher='"+teacher+"',place='"+place+"' where name='"+tempname+"'"; stmt.executeUpdate(updatesql);//执行sql语句 resp.sendRedirect(req.getContextPath()+"/index.jsp"); } catch (SQLException e) { e.printStackTrace(); } } }
