1 序言
学习java web的时候很渴望有一份完整的项目给我阅读，而网上的大部分项目拿过来都无法直接用，好不容易找到了一个学生管理系统也是漏洞百出。在此，我将边修改边学习这份代码，并且加上完全的注释，以便日后查阅。
2 项目说明
该项目为常见的学生管理系统，系统用例就不再说明。
《待补充》
3 代码分析
1 登录功能
1 首页 index.jsp
<%@ page language="java" import="java.util.*" pageEncoding="gbk"%>
<%
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%>">
<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>
<% response.sendRedirect("user/index.jsp"); %>
<%--script跳转有的浏览器不识别，比如火狐，应该使用response.sendRedict()方式更为正确，
之后好多这种情况这种情况，不再一一说明 --%>
</body>
</html>2 user/index.jsp
<%@ page language="java" import="java.util.*" pageEncoding="gb2312"%>
<%
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>欢迎登陆</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="img/css.css"> </head>
<%--调用js进行前台检查，经常用到的这一段代码，复用率相当高 --%>
<script language="JavaScript">
function login11()
{ if (document.form1.name.value == "" )
{
alert("请输入用户名!");
document.form1.name.focus();
return false;
}
if (document.form1.pwd.value == "" )
{
alert("请输入密码!");
document.form1.pwd.focus();
return false;
}
}
</script>
<STYLE>
.input7 {
BORDER-BOTTOM-WIDTH: 0px; WIDTH: 120px; COLOR: #000000; HEIGHT: 20px; BORDER-RIGHT-WIDTH: 0px
}
</STYLE>
<%--本页面为真正登陆页面,因此会有两种状态,1.登陆成功跳转到下一个页面,2是登陆失败重新登录,因此要接受登陆状态参数"error" --%>
<%
String error = (String)request.getAttribute("error");
if(error != null && error.equals("1")){
%><script>alert('用户名或密码错误!')</script><%
}
%>
<body bgcolor="#94E6FF"><%--将表单提交到servlet/user/UserLoginServlet中 --%>
<form action="servlet/user/UserLoginServlet" name="form1" method="post" onSubmit="return login11()">
<div align="center">
<p>inxi </p>
<p> </p>
<p> </p>
<table border="0" width="612" background="img/backPic1.gif" height="264" style="border: 3px double #9B9B9B">
<tr>
<td colspan="2" align="center"><font face="华文隶书" size="5">研究生工程实践管理系统<br></font><font face="华文隶书" size="3"></font></td>
</tr>
<tr>
<td width="292" align="right">用 户 名：</td>
<td width="310"><input type="text" name="name" maxlength="16" class="input7"/></td>
</tr>
<tr>
<td width="292" align="right">登录密码：</td>
<td width="310"><input type="password" name="pwd" maxlength="16" class="input7"/></td>
</tr>
<tr>
<td width="292" align="right">请选择登录身份：</td>
<td width="310">
<select name= "station">
<option value="学生">研究生</option>
<option value="指导老师">企业导师</option>
</select>
</td>
</tr>
<tr>
<td colspan="2" align="center"><input type="submit" value="登陆"> <input type="Reset" value="重置"></td>
</tr>
</table>
</div>
</form>
</body>
</html>3 UserLonginBean
这个工程中的Bean总共四个，用到的时候陆续贴出来
package bean; import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.*;
import util.*; public class UserLoginBean {
Connection conn = null;
Statement st = null;
ResultSet rs = null;
ArrayList al = new ArrayList();//容器的方式来接受出巡出来的结果，每个对象是查询结果的每一列，这里都是String对象
public int login(String name,String pwd,String station){//返回值int,代表查询状态,这里也可以自定义异常处理,复用率更高
int temp = 0;
conn = DBConn.getConn();//util类bean 这里就不贴了，只有get和close的功能
try {
st = conn.createStatement();
if(station.equals("学生")){//若身份为学生，则查询学生表，若是老师查询老师表
rs = st.executeQuery("select * from student where name='"+name+"'");
}
if(station.equals("指导老师")){//老师分为指导老师和其他老师，这里只查询指导老师，功能待扩充
rs = st.executeQuery("select * from teacher where name='"+name+"' and station='"+station+"'");
}
if(rs.next()){//若查询到有结果,则证明有该用户
String id = rs.getString("id");
String tname = rs.getString("name");
String tpwd = rs.getString("pwd");
String truename = rs.getString("truename");
String stations = rs.getString("station");
if(pwd.equals(tpwd)){//取出密码字段匹配,匹配成功取出信息,放入容器
temp = 1;//1状态代表查询成功
al.add(id);
al.add(tname);
al.add(tpwd);
al.add(stations);
al.add(truename);
}else{
temp = 2;//2 代表密码不匹配
}
}else{
temp = 3;//3代表没有该用户名
}
} catch (SQLException e) {
e.printStackTrace();
} finally{
DBConn.close(conn,st,rs);//最后关闭打开的对象,利用bean关闭
}
return temp;//返回登录状态
}
public ArrayList getArrayLst(){
return al;//返回登录查询到的结果
} }4 servlet/user/UserLoginServlet
package servlet.user; import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList; import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession; import util.Validate;
import bean.UserLoginBean; public class UserLoginServlet extends HttpServlet { /**
* Constructor of the object.
*/
public UserLoginServlet() {
super();
} /**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
//由于表单是post过来的，这里要将post转到get
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
Validate vd = new Validate();//字符转换类，不再贴了
String name = vd.getUnicode(request.getParameter("name"));
String pwd = vd.getUnicode(request.getParameter("pwd"));
String station = vd.getUnicode(request.getParameter("station"));
UserLoginBean lb = new UserLoginBean();//创建UserLoginBean对象,所有的用户操作都用得上,所以封装为Bean
int flag = lb.login(name,pwd,station);//将表单传递过来的参数登录
ArrayList al = lb.getArrayLst();//获取登录结果,若没有登录成功则为null
HttpSession session = request.getSession();
session.setAttribute("login", al);//创建session,将login设为登录成功的返回容器
String str = "";
if(flag == 2 || flag == 3){//2 3都代表登录失败
str = "/user/index.jsp";
request.setAttribute("error", "1");//设置error为登录失败状态
}else{
if(al.get(3).equals("学生"))//若是学生返回,转发至/user/student_list_3.jsp,老师则/user/student_list_2.jsp
str = "/user/student_list_3.jsp";
else str = "/user/student_list_2.jsp";
}
RequestDispatcher rd=request.getRequestDispatcher(str);
rd.forward(request,response);
} public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request,response);
} /**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occure
*/
public void init() throws ServletException {
// Put your code here
} }至此,登陆功能已经完成,接下来是选课功能
2 选课功能
1 SelectBean
package bean; import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import util.DBConn; public class SelectBean { Connection conn = null;
Statement st = null;
ResultSet rs = null; public ArrayList select(String sql,String[] args){
ArrayList al = new ArrayList();
conn = DBConn.getConn();
try {
st = conn.createStatement();
rs = st.executeQuery(sql);
while(rs.next()){
ArrayList alRow = new ArrayList();
for(int i = 0;i < args.length;i++){
alRow.add(rs.getString(args[i]));
}
al.add(alRow);//按语句查询后,依次将查询到的结果装入容器
}
} catch (SQLException e) {
// TODO 自动生成 catch 块
e.printStackTrace();
} finally{
DBConn.close(conn,st,rs);
}
return al;//返回查询结果容器
} }2 ListServlet
将需要列出来的结果都查询出来先
package servlet; import java.io.IOException;
import java.util.ArrayList; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession; import util.Validate; import bean.SelectBean; public class ListServlet extends HttpServlet { /**
* Constructor of the object.
*/
public ListServlet() {
super();
} /**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
} public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
SelectBean sb = new SelectBean(); String sql1 = "select * from teacher where station='指导老师'";
String[] args1 = {"id","name","pwd","truename","sex","age","phone","addr","station"};
ArrayList al1 = sb.select(sql1, args1);
request.setAttribute("tutor", al1);//将指导老师查询结果装入al1 String sql2 = "select * from teacher where station='指导班主任'";
String[] args2 = {"id","name","pwd","truename","sex","age","phone","addr","station"};
ArrayList al2 = sb.select(sql2, args2);
request.setAttribute("mostly", al2);//将班主任查询结果装入al2 String sql3 = "select * from projectbase";
String[] args3 = {"baseid","basename","contacts","baseaddress","basephone","baseemail","baseintroduction"};
ArrayList al3 = sb.select(sql3, args3);
request.setAttribute("captain", al3);//将项目信息装入al3 String sql4 = "select * from school";
String[] args4 = {"id","name","pwd","truename","addr","station"};
ArrayList al4 = sb.select(sql4, args4);
request.setAttribute("school", al4);//将学校信息装入al4 String sql5 = "select * from student";
String[] args5 = {"id","name","pwd","truename","sex","age","phone","addr","station"};
ArrayList al5 = sb.select(sql5, args5);
request.setAttribute("student", al5);//将学生信息装入al5 String sql11 = "select * from project,projectbase where project.baseid = projectbase.baseid";
String[] args11 = {"projectid","projectname","basename","projectinfo","state"};
ArrayList al11 = sb.select(sql11, args11);
request.setAttribute("project", al11);//关联两表,查询学生申请的项目信息,装入al11 String sql6 = "select * from course";
String[] args6 = {"id","name","times","student"};
ArrayList al6 = sb.select(sql6, args6);
request.setAttribute("course", al6);//成绩信息装入al6 Validate vd = new Validate();
String baseid = vd.getUnicode(request.getParameter("baseid"));
String sql7 = "select * from project where baseid="+baseid;
String[] args7 = {"projectid","projectname","baseid","projectinfo","state"};
ArrayList al7 = sb.select(sql7, args7);
request.setAttribute("studentleave", al7);//根据传递过来的参数,查找学生申请情况,装入al7 String sql12 = "select * from resource where baseid="+baseid;
String[] args12 = {"resourcename","resourcenumber","resourceinfor","resourcestate","baseid","teacherid","resourceid"};
ArrayList al12 = sb.select(sql12, args12);
request.setAttribute("resources", al12);//根据传递过来的参数,查询与项目相关的指定项目的资源信息,转入al12 /*
HttpSession session = request.getSession();
ArrayList adminlogin = (ArrayList)session.getAttribute("adminlogin");
if(!adminlogin.get(3).equals(1))
{
ArrayList login = (ArrayList)session.getAttribute("login");
String sql12 = "select project.projectid,projectname,projectinfo,teacherproject.state from teacherproject,project,teacher where project.projectid = teacherproject.projectid and teacherproject.id=teacher.id and teacherproject.id="+login.get(0);
String[] args12 = {"projectid","projectname","projectinfo","state"};
ArrayList al12 = sb.select(sql12, args12);
request.setAttribute("teacherlookapply", al12); // HttpSession session = request.getSession();
ArrayList login1 = (ArrayList)session.getAttribute("login");
String sql13 = "select project.projectid,projectname,projectinfo,studentproject.state from studentproject,project,student where project.projectid = studentproject.projectid and studentproject.id=student.id and studentproject.id="+login1.get(0);
String[] args13 = {"projectid","projectname","projectinfo","state"};
ArrayList al13 = sb.select(sql13, args13);
request.setAttribute("studentlookapply", al13);
}
*/ String sql8 = "select * from teacherleave";
String[] args8 = {"id","teacherid","teacher","title","content","times"};
ArrayList al8 = sb.select(sql8, args8);
request.setAttribute("teacherleave", al8);//查询老师留言,装入al8 String sql9 = "select * from grade";
String[] args9 = {"id","studentd","coursety","gradentn"};
ArrayList al9 = sb.select(sql9, args9);
request.setAttribute("grade", al9);//查询年级信息装入al9 String sql10 = "select * from taste";
String[] args10 = {"id","student","title","content","times"};
ArrayList al10 = sb.select(sql10, args10);
request.setAttribute("taste", al10);//查询学生留言
} public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request,response);
} /**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occure
*/
public void init() throws ServletException {
// Put your code here
} }3 SessLoginServlet
检查session,检查是否登陆成功
package servlet; import java.io.IOException;
import java.io.PrintWriter; import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; public class SessLoginServlet extends HttpServlet { /**
* Constructor of the object.
*/
public SessLoginServlet() {
super();
} /**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
} public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
PrintWriter pw = response.getWriter();
if(request.getSession().getAttribute("login") == null || request.getSession().getAttribute("login").equals("")){
pw.write("<script>alert('您还没有登录!');window.navigate('../user/index.jsp');</script>");
}
} public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request,response);
} /**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occure
*/
public void init() throws ServletException {
// Put your code here
} }3 user/top.jsp
页面的抬头分离写出来,别的页面时用include指令包含进来
<%@ page language="java" import="java.util.*" pageEncoding="gb2312"%>
<%
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>研究生工程实践管理系统</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="img/css.css"> </head>
<jsp:include flush="true" page="/servlet/SessLoginServlet"></jsp:include> <body>
<div align="center">
<table style="border-style: dotted; border-width: 1px">
<tr><td width="800" height="100" style="font-family: 华文行楷; font-size: 70px; border-style: ridge; border-width: 1px; color:#332590; font-style:italic" bgcolor="#C0C0C0" align="center">
研究生工程实践管理系统</td></tr>
<tr>
<td align="center" valign="top">
<table width="100%">
<tr><td align="center" height="30" background="img/bg222.gif">
<table>
<tr>
<%--
<td><a href="user/course_list.jsp">课程安排|</a></td>
<td><a href="user/studentleave.jsp">学生留言|</a></td>
<td><a href="user/teacherleave.jsp">老师留言|</a></td>
<td><a href="user/grade_list.jsp">学生成绩发布|</a></td>
--%> <td><a href="user/student_list_2.jsp">工程实践项目管理|</a></td>
<%//检查login是否登陆成功,显示教学资源管理链接
if(request.getSession().getAttribute("login") != null && !request.getSession().getAttribute("login").equals("")){
ArrayList al = (ArrayList)session.getAttribute("login");
if(al.get(3).equals("指导老师")){
%><td><a href="user/teacher_resource.jsp">实践教学资源管理|</a></td><%
}}
%>
<%-- <td><a href="">实践教学资源管理|</a></td>--%>
<td><a href="servlet/UserShowServlet">个人信息管理|</a></td>
<td><a href="user/modifypwd.jsp">修改密码|</a></td>
<%-- <td><a href="servlet/CopyOfUserShowServlet">个人信息管理|</a></td>--%>
<td><a href="servlet/RemoveServlet?login=1">注销退出</a></td>
</tr>
</table>
</td></tr>
</table>
</td>
</tr>
</table>
</div>
</body>
</html>4 StudentSelectServlet
package servlet.user; import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList; import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import bean.SelectBean; import util.Validate; public class StudentSelectServlet_1 extends HttpServlet { /**
* Constructor of the object.
*/
public StudentSelectServlet_1() {
super();
} /**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
} public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
Validate vd = new Validate();
String projectname = vd.getUnicode(request.getParameter("projectname_1"));
SelectBean sb = new SelectBean();
String sql = "select * from project,projectbase ";
String[] args = {"projectid","projectname","basename","projectinfo","state"};
sql += "where project.baseid = projectbase.baseid and projectname like '%"+projectname+"%'";
ArrayList al = sb.select(sql, args);
request.setAttribute("students", al);
RequestDispatcher rd=request.getRequestDispatcher("/user/student_list_3.jsp");
rd.forward(request,response);
} public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request,response);
} /**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occure
*/
public void init() throws ServletException {
// Put your code here
} }