初学者简单的问题

你应该放到这个目录：C:\Tomcat\webapps\InfoSite．不要放到ROOT目录下．默认也是到webapps目录下的．

楼上正解，你放错了地方了！
把你的 InfoSite目录整个挪到上级目录，变成这个样子
C:\Tomcat\webapps\InfoSite然后使用
http://localhost:8080/InfoSite 进行访问

已经把InfoSite放在C:\Tomcat\webapps\目录下试过了，sql_data.class也相应的放在了C:\Tomcat\webapps\news
还是出现相同的提示。

还是没放对
sql_data.class应当放在
C:\Tomcat\webapps\InfoSite\WEB-INF\classes也就是你的.class文件必须放在\InfoSite\WEB-INF\classes路经下

放在C:\Tomcat\webapps\WEB-INF\classes\news下面试一下。

我已经把
C:\Tomcat\webapps\InfoSite\WEB-INF\classes
C:\Tomcat\webapps\InfoSite\WEB-INF\classes\news
C:\Tomcat\webapps\news
C:\Tomcat\webapps\ROOT\InfoSite\WEB-INF\classes\news
C:\Tomcat\webapps\ROOT\WEB-INF\classes
下都放了sql_data.class文件还是不行啊！

晕了，到底tomcat的默认主目录是哪个文件的？

所有的项目都发布到C:\Tomcat\webapps下
比如C:\Tomcat\webapps\project1\
C:\Tomcat\webapps\project2\
C:\Tomcat\webapps\project3\
.............对每个项目进行访问的话就
http://localhost:8080/project1
http://localhost:8080/project2
http://localhost:8080/project3
.............如果你只有一个项目，它叫InfoSite，那么应该把他放到
C:\Tomcat\webapps\InfoSite\
项目文件，按照原目录格式放到这个下面
用http://localhost:8080/InfoSite进行访问现在你需要确认news目录究竟在什么地方
C:\Tomcat\webapps\...\InfoSite\...\WEB-INF\classes\...news\sql_data.class
打点的地方你都要好好确认一下

你先起tomcat 然后進8080里面admin里面找到你發布的項目先確定能發布出來然后再去放哪些文件
然后按照2樓或10樓的放
再試試

我把InfoSite放在C:\Tomcat\webapps\下了，在8080里的admin里也能找到InfoSite
又把sql_data.class放在C:\Tomcat\webapps\InfoSite\WEB-INF\classes和C:\Tomcat\webapps\InfoSite\WEB-INF\classes\news下了，也还是出现同样的问提。

我想不是路经的问题了，重新看了一下你的错误
>org.apache.jasper.JasperException:/InfoSite/index.jsp(5,0) The value for the useBean class attribute news/sql_data.class is invalid.上面的错误是从index.jsp里出来的，而原因是用到了sql_data.class，
你首先要确认sql_data.class是否被正确倒入到了index.jsp中，并且sql_data.class是否是编译无误的，
如果它本身就有错我想你把它放哪都解决不聊问题不过你说这个项目是从网上down,如果有源码的话最好看一看究竟是index.jsp的错，还是sql_data.class的错

index.jsp的源码如下：<%@ page contentType="text/html;charset=gb2312" %>
<%@ page language="java" import="java.sql.*"%>
<%@ page language="java" import="java.util.*"%>
<%@ page language="java" import="java.text.*"%>
<jsp:useBean id="sqlbean" scope="page" class="news/sql_data.class"/>
<HTML><HEAD><TITLE>企业内部管理信息平台</TITLE><link rel="stylesheet" href="newstyle.css" type="text/css"><META http-equiv=Content-Type content="text/html; charset=gb2312">
</HEAD>
<BODY bgColor=#ffffff leftMargin=0 topMargin=0 marginheight="0" marginwidth="0">
<CENTER><jsp:include page="header.jsp"/>
<TABLE cellSpacing=0 cellPadding=0 width=780>
  <TBODY>
  <TR>
    <TD width="159" vAlign=top><TABLE cellSpacing=0 cellPadding=0 width="97%" border=0>
        <TBODY>
<%String title;
  SimpleDateFormat sdf =new SimpleDateFormat( "MM-dd");
String sql = "Select count(*) as newsall FROM news";
ResultSet RS = sqlbean.executeQuery(sql);
  RS.first();
String newsall=RS.getString("newsall");
RS.close();
//得到今天的日期
  java.util.Date  now = new java.util.Date();
DateFormat df =  DateFormat.getDateInstance();
String s =  df.format(now);
//完成
sql = "Select count(*) as todayall FROM news where datediff(hour,d,getdate())<24";
RS = sqlbean.executeQuery(sql);
RS.first();
  String todayall=RS.getString("todayall");
RS.close();
sql = "Select sum(hit) as allhit FROM news";
RS = sqlbean.executeQuery(sql);
  RS.first();
  String allhit=RS.getString("allhit");
RS.close();%>
        <TR>
          <TD vAlign=top><br><br>
   <TABLE width="99%" border=0 align=center cellPadding=2 cellSpacing=0 class="table3">
              <TR>
                <TD><img src="images/tongji.gif" width="140" height="41"></TD>
              </TR>
              <TR>
                <TD><img src="images/jt.gif" width="17" height="19">共有信息：<font color="#000000"><strong><%=newsall%></strong></font>条 </TD>
              </TR>
              <TR>
                <TD><img src="images/jt.gif" width="17" height="19">今日更新：<font color="#000000"><strong><%=todayall%></strong></font>条</TD>
              </TR>
              <TR>
                <TD><img src="images/jt.gif" width="17" height="19">总共浏览：<font color="#000000"><strong><%=allhit%></strong>次</font></TD>
              </TR>
            </TABLE>
            </TD></TR>
        </TBODY></TABLE></td>
    <TD width="619" vAlign=top><table width="100%"  border="0" cellspacing="0" cellpadding="0">
      <tr>
        <td><br><br><img src="images/ad.jpg" width="610" height="44"></td>
      </tr>
    </table></TD>
  </TR></TBODY></TABLE>
<TABLE cellSpacing=0 cellPadding=0 width=780>
  <TBODY>
  <TR>
    <TD vAlign=top width=168>
      <TABLE style="BORDER-COLLAPSE: collapse"  height=15
      cellSpacing=0 cellPadding=0 width="100%" border=0>
        <TBODY>
        <TR>
          <TD align="center" class="unnamed1" >-=热点关注=-</TD>
          <TD>
            <DIV align=right></DIV></TD></TR></TBODY></TABLE>
      <TABLE cellSpacing=0 cellPadding=0 width="100%">
        <TBODY>
        <TR>
          <TD vAlign=center><TABLE style="BORDER-COLLAPSE: collapse"
             cellSpacing=0 cellPadding=0 width=154
            border=0>
              <TBODY>
              <TR>
                <TD width=10 height=36></TD>
                <TD vAlign=top width=134>
<% sql = "Select top 10 id,title,hit  FROM news order by hit desc";
RS = sqlbean.executeQuery(sql);
while (RS.next()){%>
<img src=images/ico1.gif><A href='show.jsp?id=<%=RS.getString("id")%>' title="<%=RS.getString("title")%>" class="TableLink"><%title=RS.getString("title");
if (title.length()>9){
title=title.substring(0,8);
out.println(title+"...");}else{
out.println(title);}
%></a><FONT color=#999999><%=RS.getString("hit")%></font><BR>
<%}
RS.close();%></TD>
                <TD width=10></TD>
              </TR></TBODY></TABLE></TD>
        </TR></TBODY></TABLE>
      <TABLE cellSpacing=0 cellPadding=0 width="100%">
        <TBODY>
          <TR>
            <TD vAlign=center><TABLE   cellSpacing=0 cellPadding=0 width=154   border=0>
                <TBODY>
                  <TR>
                    <TD></TD>
                    <TD align="center" vAlign=top class="unnamed1">-=最新加入=-</TD>
                    <TD></TD>
                  </TR>
                  <TR>
                    <TD width=10 height=36></TD>
                    <TD vAlign=top width=134>
                      <% sql = "Select top 10 id,title,hit  FROM news order by id desc";
RS = sqlbean.executeQuery(sql);
while (RS.next()){%>
                      <img src=images/ico1.gif><A href='show.jsp?id=<%=RS.getString("id")%>' title="<%=RS.getString("title")%>" class="TableLink"><%
  title=RS.getString("title");
  if (title.length()>9){
title=title.substring(0,8);
out.println(title+"...");}else{
out.println(title);}
  %></a> <FONT color=#999999><%=RS.getString("hit")%></font><BR>
                      <%}
RS.close();%></TD>
                    <TD width=10></TD>
                  </TR>
                </TBODY>
            </TABLE></TD>
          </TR>
        </TBODY>
      </TABLE></TD>
    <TD width="610" valign="top">
      <TABLE style="BORDER-COLLAPSE: collapse"  cellSpacing=0
      cellPadding=0 width=610 border=0>
        <TBODY><tr><td colspan="4"><TABLE style="BORDER-COLLAPSE: collapse"  cellSpacing=0
      cellPadding=0 width=610 border=0>
        <TBODY>
        <TR>
          <TD width="309"><TABLE style="BORDER-COLLAPSE: collapse"
            cellSpacing=0 cellPadding=3 width=95% border=0>
            <TBODY>
              <% ResultSet RS_root = sqlbean.executeQuery("select top 4 class from class where

sql_data.java的源码如下：
//sql_data.java
package news;
import java.sql.*;
public class sql_data{
String sDBDriver = "com.microsoft.jdbc.sqlserver.SQLServerDriver";
String  url="jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=InfoSite";    String  user="sa";
String  password="sa";
Connection  conn=  null;
Statement stmt = null;
ResultSet rs = null;
public sql_data()
{
try
{Class.forName(sDBDriver);
}
catch(java.lang.ClassNotFoundException e)
{
System.err.println("sql_data(): " + e.getMessage());
}
}
public void executeInsert(String sql)
{
try
{//conn = DriverManager.getConnection(url,user,password);
conn = DriverManager.getConnection(url,user,password);
stmt = conn.createStatement();
stmt.executeUpdate(sql);
stmt.close();
conn.close();
}
catch(SQLException ex)
{System.err.println("sql_data.executeUpdate:"+ex.getMessage());
}
}
public ResultSet executeQuery(String sql)
{
try
{
conn = DriverManager.getConnection(url,user,password);
stmt = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY);
    rs = stmt.executeQuery(sql);
}
catch(SQLException ex)
{
System.err.println("sql_data.executeQuery:"+ex.getMessage());
}
return rs;
}
public void executeUpdate(String sql)
{
    try {
conn = DriverManager.getConnection(url,user,password);
stmt = conn.createStatement();
    stmt.executeUpdate(sql);
stmt.close();
    conn.close();
    }
    catch(SQLException ex) {
      System.err.println("aq.executeQuery: " + ex.getMessage());
    }
}
public void executeDelete(String sql)
{
try
{conn = DriverManager.getConnection(url,user,password);
stmt = conn.createStatement();
stmt.executeUpdate(sql);
stmt.close();
    conn.close();
}
catch(SQLException ex)
{
System.err.println("sql_data.executeDelete:"+ex.getMessage());
}
}
public void closeStmt(){
    try{
      stmt.close();
     }
    catch(SQLException e){
      e.printStackTrace();
     }
  }public void closeConn(){
    try{
      conn.close();
     }
    catch(SQLException e){
      e.printStackTrace();
   }
  }
}

果然如此,我们都被你以上来就说的路径给迷惑住了,都在全力帮你解决路径问题,劲都使错地方了你将index.jsp的第5行改成下面这样<jsp:useBean id="sqlbean" scope="page" class="news.sql_data"/>
或者
<jsp:useBean id="sqlbean" scope="page" type="news.sql_data"/>
其它地方还有错没还不太清楚,先把这改了

o(∩_∩)o
改成<jsp:useBean id="sqlbean" scope="page" class="news.sql_data"/>后终于有变化了type Exception reportmessage description The server encountered an internal error () that prevented it from fulfilling this request.exception org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:372)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:966)
org.apache.jsp.index_jsp._jspService(index_jsp.java:66)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:324)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
root cause java.lang.NullPointerException
org.apache.jsp.header_jsp._jspService(header_jsp.java:65)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:324)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:966)
org.apache.jsp.index_jsp._jspService(index_jsp.java:66)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:324)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

空指针异常是不是因为使用TOMCAT的问题，代码没有问题了吧.

还是代码问题,index.jsp里用到java代码的地方出错具体是哪从错误信息中还看不出来

ls的帮他解决下。
LZ你把工程发布到下载区，把下载资源地址告诉我们

系统下载地址：
http://dl2.csdn.net/down4/20080202/02224905262.rar
数据库下载地址：
http://dl2.csdn.net/down4/20080202/02230353856.rar麻烦大家了，o(∩_∩)o 感谢！

phyeas 兄弟是在什么环境下运行的呢?

调试易

初学者简单的问题

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