我的程序包括两个部分
第一部分:login.html
这个部分是没问题的,我给它放在tomcat4的examples/jsp目录下
实现的是界面.
第二部分:verfiylogin.jsp
是用来和数据库实现连接的,源码如下:
<%@ page language= "java " contentType= "text/html; charset=UTF-8 "
pageEncoding= "UTF-8 "%>
<%@ page
import= "com.wxpn.tutorial.db.DB,com.wxpn.tutorial.db.ConnectionPool "%>
<%@ page
import= "java.sql.Connection,java.sql.Statement,java.sql.ResultSet,java.sql.SQLException "%>
<html>
<head>
<meta http-equiv= "Content-Type " content= "text/html; charset=gb2312 ">
<meta http-equiv= "Content-Language " content= "zh-cn ">
<title> 登录 </title>
</head>
<body>
<div align=center> <font color= "red "> <strong> <%//获取提交的用户名：
String strUserName = request.getParameter( "txtUserName ");
//获取提交的密码：
String strPassword = request.getParameter( "txtPassword ");
if((strUserName ==null)||(strUserName.equals( " "))||(strUserName.length()> 20)){
response.sendRedirect( "login.html ");
}
if((strPassword ==null)||(strPassword.equals( " "))||(strPassword.length()> 20)){
response.sendRedirect( "login.html ");
}
//创建数据库连接对象：
ConnectionPool connPool = DB.getConnPool();
Connection conn = connPool.getConnection();
Statement stmt = null;
ResultSet rs = null;
try {
int nextMessageid = 0;
String relative_path = null;
//sql语句：
String sql = "select * from userInfo where username= ' "
+ strUserName + " ' and userpwd= ' " + strPassword + " ' ";
//创建数据记录集对象：
stmt = conn.createStatement();
//执行sql语句，返回一个记录集到rs：
rs = stmt.executeQuery(sql);
//如果记录集为非空，表明有相匹配的用户名和密码，登录成功：
if (rs.next()) {
//登录成功时,把strUserName设成session变量UserName
session.setAttribute( "UserName ",strUserName);
out.println( "登录成功! ");
} else {
//否则（记录集为空），表明失败：
out.println( "登录失败! ");
}
} catch (SQLException sqlExc) {
sqlExc.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
} finally {
//关闭连接，释放数据库资源：
try {
if (rs != null) {
rs.close();
}
if (stmt != null) {
stmt.close();
}
connPool.freeConnection(conn);
} catch (SQLException sqlExc) {
sqlExc.printStackTrace();
}
}
%> </strong> </font> </div>
</body>
</html>
问提是当我运行http://localhost:8080/examples/jsp/login.html
时,在其中输入用户名和密码时,就出现如下错误:
org.apache.jasper.JasperException: Unable to compile class for JSP
An error occurred at line: 13 in the jsp file: /jsp/verifylogin.jsp