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jsp连接数据库有关问题

发布时间: 2013-09-11 17:59:59 作者: rapoo

jsp连接数据库问题
<%@ page contentType= "text/html; charset=gb2312 " language= "java " import= "java.sql.* " errorPage= "exception.jsp " %>
<html>
   <body>
   <%/***********************************************
/*
/*DbTest.java
/*http://www.knowsky.com
/******************************************* */

public class DbTest {

 Connection con;
 Statement sta;
 ResultSet rs;

 String driver;
 String url;
 String user;
 String pwd;
 public DbTest()
 {
  driver = "com.microsoft.jdbc.sqlserver.SQLServerDriver ";;
  url = "jdbc:microsoft:sqlserver://localhost:1433;DatabaseName =guolv ";
  user = "sa ";
  pwd = "pass ";
  init();
 }
 public void init()
 {
  try{
   Class.forName(driver);
   System.out.println( "driver is ok ");
   con = DriverManager.getConnection(url,user,pwd);
   System.out.println( "conection is ok ");
   sta = con.createStatement();
   rs = sta.executeQuery( "select * from logonerr ");
   while(rs.next())
   System.out.println(rs.getInt( "id "));
  }catch(Exception e)
  {
   e.printStackTrace();
  }
 }

 public static void main(String args [])//自己替换[]
 {
  new DbTest();
 }
}
  %>
   </body>
   </html>


以上是代码
下面是错误代码
刚学习jsp 不怎么看的懂
type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

org.apache.jasper.JasperException: org.apache.jasper.JasperException: Unable to load class for JSP
org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:156)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:329)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)

root cause

org.apache.jasper.JasperException: Unable to load class for JSP
org.apache.jasper.JspCompilationContext.load(JspCompilationContext.java:600)
org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:144)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:329)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)

root cause

java.lang.ClassNotFoundException: org.apache.jsp.conn_005fsql_jsp
java.net.URLClassLoader$1.run(Unknown Source)
java.security.AccessController.doPrivileged(Native Method)
java.net.URLClassLoader.findClass(Unknown Source)
org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:134)
org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:66)


org.apache.jasper.JspCompilationContext.load(JspCompilationContext.java:598)
org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:144)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:329)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)



[解决办法]
应该是驱动找不到:com.microsoft.jdbc.sqlserver.SQLServerDriver
有没有将驱动放入lib文件里?
[解决办法]
Unable to load class for JSP
如果你确定你驱动没问题,那么删除掉work目录下的文件,重起服务器,再试试看
[解决办法]
不好意思,刚没看代码就回答了...
问题很明显,你在JSP里定义了public class这样是不行的,因为JSP本身是一个servlet也就是一个class,而它自己是缺省public 的,而一个class只允许有一个public class定义,所以就没办法编译JSP...你把class定义去掉试试
[解决办法]
调用的类库文件找不到,估计是驱动jar文件没有在classpath路径里面
把驱动jar文件放到lib文件夹下,并设置classpath

开始你不要搞那么复杂啊,网上的程序也不是抄来就能直接用的,要有环境设置啊

[解决办法]
建议兄弟,先好好看看书本再试,,,
我的异常网推荐解决方案:The server encountered an internal error () that prevented it from fulfilling this request.,http://www.myexception.cn/java-web/317.html

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