login.jsp
<%@ page contentType="text/html;charset=gb2312"%>
<html>
<head>
<center>
<titl><h1>JDBC+JSP 留言管理程序</h1></title>
<hr>
<br>
<form action="loginconf.jsp" method="post">
<table width="1">
<tr>
<td colspan="2">用戶登錄</td>
</tr>
<tr>
<td >用戶名:</td>
<td><input type="text" name="id"></td>
</tr>
<tr>
<td>密 碼:</td>
<td><input type="password" name="password"></td>
</tr>
<tr>
<td><input type="submit" value="登錄"></td>
<td><input type="reset" value="重置"></td>
</tr>
</table>
</form>
<%
// 判斷是否有錯誤信息，如果有則打印
// 如果沒有此段代碼，則顯示時會直接打印null
if(request.getAttribute("err")!=null)
{
%>
<h4><font color="red"><%=request.getAttribute("err")%></font></h4>
<%
}
%>
</center>
</head>
<body>
</body>
</html>
jdbc.jsp
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import = "java.sql.*"%>
<html>
<head>
<center>
<titl><h1>JDBC+JSP 留言管理程序</h1></title>
<hr>
<br>
</center>
</head>
<body>
<%--
使用JDBC連接ORACLE數據庫
--%>
<%!
String DBDRIVER = "oracle.jdbc.driver.OracleDriver";
String DBURL = "jdbc:oracle:thin:@192.168.1.100:1521:YK";
String DBNAME = "scott";
String DBPASS = "tiger";
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
%>
<%
boolean flag = false;
//接收參數
String name = request.getParameter("id");
String password = request.getParameter("password");
%>
<%
//連接數據庫
String sql = "SELECT name from login where name=? and password=?";
try {
Class.forName(DBDRIVER);
conn = DriverManager.getConnection(DBURL,DBNAME,DBPASS);
pstmt = conn.prepareStatement(sql);
pstmt.setString(1,name);
pstmt.setString(2,password);
rs = pstmt.executeQuery();
if(rs.next()) {
out.println(rs.getString("name"));
flag = true;
session.setAttribute("uname",rs.getString("name"));
} else {
request.setAttribute("err","用戶名或密碼錯誤!");
}
rs.close();
pstmt.close();
conn.close();
}catch (Exception e) {
out.println(e);
}
%>
<%
//跳轉
if(flag) {
//如果用戶登錄成功，則跳轉到歡迎界面
//否則提示用戶登錄失敗
%>
<jsp:forward page="loginsuccessf.jsp" />
<%
}
else {
%>
<jsp:forward page="login.jsp"/>
<%
}
%>
</body>
</html>
success.jsp
<%@ page contentType="text/html;charset=gb2312"%>
<%@ page import="java.sql.*"%>
<html>
<head>
<center>
<titl><h1>JDBC+JSP 留言管理程序</h1></title>
<hr>
<br>
</center>
</head>
<body>
<%
if(session.getAttribute("uname")!=null) {
//用戶已登錄成功
%>
<center><h2>歡迎<font color="red" size=12><%=session.getAttribute("uname")%></font>進入留言管理系統
</h2></center>
<%
}
else {
//未登錄，提示用戶登錄
response.setHeader("refresh","2;URL=login.jsp");
%>
您還未登錄，2秒將後自動跳轉到登錄界面<br>
如果沒有自動跳轉，請<a href="login.jsp"><font color="greed">點擊</font></a>這裏登錄！<br>
<%
}
%>
</body>
</html>
