SourceForge Submitter: bcoutinho .
I got a NullPointerException when a tried to graph a
Dataset generated by a Snapshot monitor.

I??????ve created a snapshot monitor for FreeMemory
ServerInfo attribute. Started it and after some time I
stopped it. It generated some 150 lines of data (I can
see with "Show Dataset" button).

But when I click "Graph Dataset", I got the following
exception:

15:21:56,329 ERROR [Engine] StandardWrapperValve[Manage
Snapshot]: Servlet.service() for servlet Manage
Snapshot threw exception
java.lang.NullPointerException
at
org.jfree.data.DefaultTableXYDataset.getDomainRange()Lorg.jfree.data.Range;(DefaultTableXYDataset.java:537)
at
org.jfree.data.DatasetUtilities.getDomainExtent(Lorg.jfree.data.Dataset;)Lorg.jfree.data.Range;(DatasetUtilities.java:162)
at
org.jfree.chart.plot.XYPlot.getDataRange(Lorg.jfree.chart.axis.ValueAxis;)Lorg.jfree.data.Range;(XYPlot.java:2706)
at
org.jfree.chart.axis.NumberAxis.autoAdjustRange()V(NumberAxis.java:350)
at
org.jfree.chart.axis.NumberAxis.configure()V(NumberAxis.java:333)
at
org.jfree.chart.axis.Axis.setPlot(Lorg.jfree.chart.plot.Plot;)V(Axis.java:715)
at
org.jfree.chart.plot.XYPlot.<init>(Lorg.jfree.data.XYDataset;Lorg.jfree.chart.axis.ValueAxis;Lorg.jfree.chart.axis.ValueAxis;Lorg.jfree.chart.renderer.XYItemRenderer;)V(XYPlot.java:410)
at
org.jfree.chart.ChartFactory.createXYLineChart(Ljava.lang.String;Ljava.lang.String;Ljava.lang.String;Lorg.jfree.data.XYDataset;Lorg.jfree.chart.plot.PlotOrientation;ZZZ)Lorg.jfree.chart.JFreeChart;(ChartFactory.java:1289)
at
org.jboss.console.plugins.monitor.ManageSnapshotServlet.doit(Ljavax.servlet.http.HttpServletRequest;Ljavax.servlet.http.HttpServletResponse;)V(ManageSnapshotServlet.java:192)
at
org.jboss.console.plugins.monitor.ManageSnapshotServlet.doPost(Ljavax.servlet.http.HttpServletRequest;Ljavax.servlet.http.HttpServletResponse;)V(ManageSnapshotServlet.java:42)
at
javax.servlet.http.HttpServlet.service(Ljavax.servlet.http.HttpServletRequest;Ljavax.servlet.http.HttpServletResponse;)V(HttpServlet.java:717)
at
javax.servlet.http.HttpServlet.service(Ljavax.servlet.ServletRequest;Ljavax.servlet.ServletResponse;)V(HttpServlet.java:810)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Ljavax.servlet.ServletRequest;Ljavax.servlet.ServletResponse;)V(ApplicationFilterChain.java:237)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(Ljavax.servlet.ServletRequest;Ljavax.servlet.ServletResponse;)V(ApplicationFilterChain.java:157)
at
org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(Ljavax.servlet.ServletRequest;Ljavax.servlet.ServletResponse;Ljavax.servlet.FilterChain;)V(ReplyHeaderFilter.java:75)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Ljavax.servlet.ServletRequest;Ljavax.servlet.ServletResponse;)V(ApplicationFilterChain.java:186)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(Ljavax.servlet.ServletRequest;Ljavax.servlet.ServletResponse;)V(ApplicationFilterChain.java:157)
at
org.apache.catalina.core.StandardWrapperValve.invoke(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;Lorg.apache.catalina.ValveContext;)V(StandardWrapperValve.java:214)
at
org.apache.catalina.core.StandardValveContext.invokeNext(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;)V(Optimized
Method)
at
org.apache.catalina.core.StandardPipeline.invoke(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;)V(StandardPipeline.java:520)
at
org.apache.catalina.core.StandardContextValve.invokeInternal(Lorg.apache.catalina.Wrapper;Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;)V(StandardContextValve.java:198)
at
org.apache.catalina.core.StandardContextValve.invoke(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;Lorg.apache.catalina.ValveContext;)V(StandardContextValve.java:152)
at
org.apache.catalina.core.StandardValveContext.invokeNext(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;)V(Optimized
Method)
at
org.jboss.web.tomcat.security.CustomPrincipalValve.invoke(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;Lorg.apache.catalina.ValveContext;)V(Optimized
Method)
at
org.apache.catalina.core.StandardValveContext.invokeNext(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;)V(Optimized
Method)
at
org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;Lorg.apache.catalina.ValveContext;)V(Optimized
Method)
at
org.apache.catalina.core.StandardValveContext.invokeNext(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;)V(Optimized
Method)
at
org.apache.catalina.core.StandardPipeline.invoke(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;)V(StandardPipeline.java:520)
at
org.apache.catalina.core.StandardHostValve.invoke(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;Lorg.apache.catalina.ValveContext;)V(StandardHostValve.java:137)
at
org.apache.catalina.core.StandardValveContext.invokeNext(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;)V(Optimized
Method)
at
org.apache.catalina.valves.ErrorReportValve.invoke(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;Lorg.apache.catalina.ValveContext;)V(ErrorReportValve.java:118)
at
org.apache.catalina.core.StandardValveContext.invokeNext(Lorg.apache.catalina.Request;Lorg.apache.catalina.Response;)V(Optimized
Method)

I??????ve downloaded JBoss 4.0.0, and built in on a Windows
2000 with Sun JDK 1.4.2_05.

Thanks!
–
Regards,
Bill Coutinho.