jsp頁面body裏的內容：
<center>
<font size=20>歡迎來到在線考試系統！</font>
<form method="post" action="./servlet/CheckLogin">
<table>
<tr>
<td>用戶名:</td>
<td>
<label><input type="text" name="username"></label>
</td>
</tr>
<tr>
<td>密碼：</td>
<td>
<label><input type="text" name="password"></label>
</td>
<tr>
</table>
<label><a href="register.jsp">註冊</a></label>?
<label><input type="submit" name="tijiao" value="提交"></label>
<label><input type="reset" name="quxiao" value="取消"></label>
</form>
</center>
dao裏驗證方法的內容：
public ExamUser validator(ExamUser instance){
String sql="select * from exam_user where username=? and password=?";
conn cdb=conn.createInstance();
//PreparedStatement ps=cdb.setPs(sql);
cdb.setPs(sql);// 設置建立連接
try {
cdb.getPs().setString(1,instance.getUsername());
cdb.getPs().setString(2,instance.getPassword());
cdb.setRs(cdb.Query2());
if(cdb.getRs().next()){
instance.setUsername(cdb.getRs().getString(2));
instance.setPassword(cdb.getRs().getString(3));
instance.setSno(cdb.getRs().getString(4));
instance.setGender(cdb.getRs().getString(5));
instance.setXibie(cdb.getRs().getString(6));
instance.setClasses(cdb.getRs().getString(7));
instance.setChengji(cdb.getRs().getInt(8));
instance.setPower(cdb.getRs().getInt(9));
}
else{
instance=null;
}
} catch (SQLException e) {
e.printStackTrace();
}
finally{
cdb.closeCon();
}
return instance;
}
servlet裏dopost方法的內容：
request.setCharacterEncoding("gbk");
response.setCharacterEncoding("gbk");
PrintWriter out = response.getWriter();
ExamUser eu = new ExamUser();//ExamUser類的對象
String username = request.getParameter("username");
String password = request.getParameter("password");
if(username==null||username.length()<1){
out.println("<script language=javascript>window.location.href='../login.jsp?err=username';</script>");
out.flush();
out.close();
}
if(password==null||password.length()<1){
out.println("<script language=javascript>window.location.href='../login.jsp?err=password';</script>");
out.flush();
out.close();
}
eu.setUsername(username);//表單裏的賦值給javaBean
eu.setPassword(password);
ExamUserDAO dao = DaoFactory.getExamUserDAO();
eu=dao.validator(eu);//檢查對象是否合格
HttpSession session = request.getSession();
if(eu!=null){//該對象通過，記住它，頁面跳轉
session.setAttribute("examUser",eu);//記住這個對象
session.setAttribute("username", eu.getUsername());
if(eu.getPower()==1)
{
request.getRequestDispatcher("../admin.jsp").forward(request, response);}
else
{request.getRequestDispatcher("../student.jsp").forward(request, response); }
}else{
out.println(username+"sssssssssss");
out.println("<script language=javascript>window.location.href='../login.jsp?err=invalidate';</script>");
out.flush();
out.close();
}
out.flush();
out.close();