Hello all,
I'm relatively new to JSPs, but I was able to successfully and install one
other tag library (The Date/Time taglib). I'm not having much luck with the
dbtags library, though.
Basically, I'm running a MySQL database using the 2.0.4 MM JDBC driver and
while the page attempts a connection with the database (this I know because
if I leave out a correct username or password the error message indicates a
login-error) I get a:
java.lang.NullPointerException
at org.apache.taglibs.jdbc.resultset.ResultSetTag.doStartTag(
Now, I've read that this taglib requires either Jave 2 EE (rather than
Standard, which is what I'm using) or a driver that supports the Optional
API for JDBC 2.0.
I suspect that my JDBC driver may not be truly 2.0 compliant. Doesn't
anyone have any suggestions for different drivers to try, or some insight on
something I might be doing wrong here?
Thanks in advance!
The full code examples follow:
Here's the jsp source:
<%@ taglib uri="http://jakarta.apache.org/taglibs/dbtags"; prefix="sql" %>
<%-- open a database connection --%>
<sql:connection id="conn1">
<sql:url>jdbc:mysql://probably.shouldn't tell</sql:url>
<sql:driver>org.gjt.mm.mysql.Driver</sql:driver>
<sql:userId>not.telling</sql:userId>
<sql:password>not.telling</sql:password>
</sql:connection>
<%-- open a database query -->
<table>
<sql:statement id="stmt1" conn="conn1">
<sql:query>
select articleID from article
</sql:query>
<%-- loop through the rows of your query --%>
<sql:resultSet id="rset2">
<tr>
<td>
<sql:getColumn position="1"/>
</td>
</tr>
</sql:resultSet>
</sql:statement>
</table>
<%-- close database connection --%>
<sql:closeConnection conn="conn1"/>
Here's the full error message:
Error: 500
Location: /hnwapps/hnwNewsletter/database_test.jsp
Internal Servlet Error:
javax.servlet.ServletException
at
org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImp
l.java:459)
at
hnwNewsletter._0002fhnwNewsletter_0002fdatabase_0005ftest_0002ejspdatabase_0
005ftest_jsp_9._jspService(_0002fhnwNewsletter_0002fdatabase_0005ftest_0002e
jspdatabase_0005ftest_jsp_9.java:351)
at
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:119)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at
org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.ja
va:177)
at
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:318)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:391)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at
org.apache.tomcat.core.ServletWrapper.doService(ServletWrapper.java:404)
at org.apache.tomcat.core.Handler.service(Handler.java:286)
at
org.apache.tomcat.core.ServletWrapper.service(ServletWrapper.java:372)
at
org.apache.tomcat.core.ContextManager.internalService(ContextManager.java:79
7)
at
org.apache.tomcat.core.ContextManager.service(ContextManager.java:743)
at
org.apache.tomcat.service.connector.Ajp13ConnectionHandler.processConnection
(Ajp13ConnectionHandler.java:160)
at
org.apache.tomcat.service.TcpWorkerThread.runIt(PoolTcpEndpoint.java:416)
at
org.apache.tomcat.util.ThreadPool$ControlRunnable.run(ThreadPool.java:498)
at java.lang.Thread.run(Thread.java:484)
Root cause:
java.lang.NullPointerException
at
org.apache.taglibs.jdbc.resultset.ResultSetTag.doStartTag(ResultSetTag.java:
128)
at
hnwNewsletter._0002fhnwNewsletter_0002fdatabase_0005ftest_0002ejspdatabase_0
005ftest_jsp_9._jspService(_0002fhnwNewsletter_0002fdatabase_0005ftest_0002e
jspdatabase_0005ftest_jsp_9.java:261)
at
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:119)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at
org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.ja
va:177)
at
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:318)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:391)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at
org.apache.tomcat.core.ServletWrapper.doService(ServletWrapper.java:404)
at org.apache.tomcat.core.Handler.service(Handler.java:286)
at
org.apache.tomcat.core.ServletWrapper.service(ServletWrapper.java:372)
at
org.apache.tomcat.core.ContextManager.internalService(ContextManager.java:79
7)
at
org.apache.tomcat.core.ContextManager.service(ContextManager.java:743)
at
org.apache.tomcat.service.connector.Ajp13ConnectionHandler.processConnection
(Ajp13ConnectionHandler.java:160)
at
org.apache.tomcat.service.TcpWorkerThread.runIt(PoolTcpEndpoint.java:416)
at
org.apache.tomcat.util.ThreadPool$ControlRunnable.run(ThreadPool.java:498)
at java.lang.Thread.run(Thread.java:484)
..................................................
Marc Elliott
Director of Information Architecture / HNW Inc.
Digital Solutions for High-Net-Worth Marketers
ph: 617-243-9199 x224
fx: 815-327-4167
