就是把你第一次的local改为localhost或127.0.0.1就可以了

你这个好象也用不到改server.xml

我看错了
但是没看懂你的类的作用
你的数据库里有没有数据啊
怎么建的表 能看看么？

数据库表在最上面:只有两行:
数据库里有数据,只有两行:测试的:现在我又改了,还是不行:
出错如下:
type Exception report

message

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

exception

org.apache.jasper.JasperException: Exception in JSP: /index.jsp:6

3: <jsp:useBean id="conn" scope="page" class="firm.firm"/>
4: <%//st=conn.createStatement();
5: String sql="select * from Guest_Book";
6: ResultSet rs=conn.executeQuery(sql);
7: //ResultSet executeQuery(String sql);
8: //String ID=rs.getString("ID");
9: //while(rs.next()){

Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:504)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:393)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

root cause

java.lang.NullPointerException
firm.firm.executeQuery(firm.java:68)
org.apache.jsp.index_jsp._jspService(index_jsp.java:60)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:332)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

note The full stack trace of the root cause is available in the Apache Tomcat/5.5.17 logs.

[此贴子已经被作者于2006-9-18 12:53:41编辑过]

你在类里添加个main方法来单独测试一下
先不要放入jsp中

public int executeUpdate_id(String sql)
{
int result = 0;
try
{
conn = getConnection();
stmt = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
ResultSet.CONCUR_READ_ONLY);
result = stmt.executeUpdate(sql);
String ID = "select @@IDENTITY as id";
rs = stmt.executeQuery(ID);
if (rs.next())
{
int autoID = rs.getInt("id");
result = autoID;
}
}
catch (SQLException ex)
{
result = 0;
}
return result;
}

红色的地方可以这样写吗

可以这样写,如果失败,它会返回一个小于0的数:

是吗 我一会试试
不过你最新改的我觉得太复杂了
又不是连接池没有必要这么写吧

编译不了
int result = 0;
result = stmt.executeUpdate(sql);

为什么在你的代码里能便宜
我的就不行呢
int result = 0;
result = stmt.executeUpdate(sql);