Re: maybe a serialization error?

Felipe,

In looking at the code the most likely cause of this error is that your
code is working with the ResultSet after it has been closed. That is
the only reason I can see that would generate a NullPointerException
when calling the beforeFirst() method.

thanks,
--Barry

Felipe Schnack wrote:
> Hi all,
> I have a strange problem using pgsql driver in my Tomcat 4.1 server. I have an object that manages my sql queries (simply put: it receives the sql expression, executes it and stores the resultset in a private variable). For some reason, if I get one of these objects of mine and set it as an page attribute in my tomcat application, the following error occurs when I try fetch data from it. Why? I guess it's a serialization issue, because I'm sure this query returns data...
>
> java.lang.NullPointerException
> at org.postgresql.jdbc2.AbstractJdbc2ResultSet.beforeFirst(AbstractJdbc2ResultSet.java:204)
> at org.apache.commons.dbcp.DelegatingResultSet.beforeFirst(DelegatingResultSet.java:188)
> at com.w2.infra.db.DbVector.first(DbVector.java:175)
> at com.w2.infra.tags.logic.IterateTag.doTag(IterateTag.java:27)
> at com.w2.infra.tags.Taglib.doStartTag(Taglib.java:116)
> at org.apache.jsp.vest2_jsp._jspx_meth_w2_iterateTag_0(vest2_jsp.java:553)
> at org.apache.jsp.vest2_jsp._jspx_meth_w2_beanLoaderTag_0(vest2_jsp.java:524)
> at org.apache.jsp.vest2_jsp._jspService(vest2_jsp.java:238)
> at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:137)
> at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
> at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:210)
> at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:295)
> at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
> at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
> at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:684)
> at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:432)
> at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:356)
> at com.w2.infra.mvc.FormHandler.redirectTo(FormHandler.java:102)
> at com.w2.vest.forms.FormCadsVest.doForm(FormCadsVest.java:54)
> at com.w2.infra.servlets.FormManager.service(FormManager.java:61)
> at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:247)
> at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
> at com.w2.infra.servlets.ErrorPageFilter.doFilter(ErrorPageFilter.java:25)
> at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:213)
> at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:193)
> at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256)
> at
>