Error on X need to restart web application

[2002 JI Open Discussion]

By: Marco - marco_010177

Error on X need to restart web application

2003-08-29 05:45

Hello,

 

I wrote a servlet to display a PDF report to web users fetching data from a database.

The application works fine but there is a strange problem with X server.

If the first call of the servlet have a problem with X server (like forgot to launch the X server...), this cause an (obvious) exception like this:

 

[Exception stack trace]

java.lang.InternalError: Can't connect to X11 window server using ':1.0' as the value of the DISPLAY variable.

at sun.awt.X11GraphicsEnvironment.initDisplay(Native Method)

at sun.awt.X11GraphicsEnvironment.<clinit>(X11GraphicsEnvironment.java:77)

at java.lang.Class.forName1(Native Method)

at java.lang.Class.forName(Class.java(Compiled Code))

at java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment(GraphicsEnvironment.java:72)

at dori.jasper.engine.fill.JRBaseFiller.<clinit>(JRBaseFiller.java:210)

at dori.jasper.engine.fill.JRFiller.fillReport(JRFiller.java:150)

at dori.jasper.engine.JasperFillManager.fillReport(JasperFillManager.java:350)

at dori.jasper.engine.JasperFillManager.fillReport(JasperFillManager.java:290)

at dori.jasper.engine.JasperRunManager.runReportToPdfFile(JasperRunManager.java:245)

at miaapp.report.ReportManager.createPdf(ReportManager.java:33)

at miaapp.servlet.PrintReportServlet.createReport(PrintReportServlet.java:305)

at miaapp.servlet.PrintReportServlet.doService(PrintReportServlet.java:144)

at miaapp.servlet.MIAServlet.doGet(MIAServlet.java:385)

 

But, now, if I start the X server the servlet still cannot create the report and throw this exception:

 

[Exception stack trace]

java.lang.NoClassDefFoundError: dori/jasper/engine/fill/JRVerticalFiller

at dori.jasper.engine.fill.JRFiller.fillReport(JRFiller.java:150)

at dori.jasper.engine.JasperFillManager.fillReport(JasperFillManager.java:350)

at dori.jasper.engine.JasperFillManager.fillReport(JasperFillManager.java:290)

at dori.jasper.engine.JasperRunManager.runReportToPdfFile(JasperRunManager.java:245)

at miaapp.report.ReportManager.createPdf(ReportManager.java:33)

at miaapp.servlet.PrintReportServlet.createReport(PrintReportServlet.java:305)

at miaapp.servlet.PrintReportServlet.doService(PrintReportServlet.java:144)

at miaapp.servlet.MIAServlet.doGet(MIAServlet.java:385)

 

The only way to resolve the problem is to restart the Web Application on Websphere (without restart X).

 

I have used JasperReports ver. 0.4.5 (I also tried with 0.5.0 without difference).

The application server is Websphere App Server rel 5.0.2, with JVM 1.3.1 (exactly "J2RE 1.3.1 IBM").

I tried with two X servers: Xvnc (on Linux) and Xvfb, the problem and the exception are the same.

Operating system is IBM AIX but I've tried on Linux (RedHat 7.3) whith the same result.

 

I don't know if this is a bug but appear that JasperReport "remember" the bad startup with X, are there any way to reset this "memory" ?

I need a way to avoid to restart the entire web application.

 

Thank you.

 

 

 

 

By: lihongbing - hongbingli

RE: Error on X need to restart web application

2003-09-02 01:43

Hi

we have same problem with linux/tomcat,but it's not the poblem of jasper ,it's webserver who remember the bad things. I delete the work directory of the web server.

this may help for you.

 

 

 

 

By: Marco - marco_010177

RE: Error on X need to restart web application

2003-09-03 00:56

Thank you for your suggestions but I don't understand why the problem is on the web server, I think the problem is on application server (Tomcat for you), the web server has only a cache (I don't think that web server has any kind of "logic").

But the major question is: what is the "work directory" ? The PDF is composed in memory, without any files (except for report template and eventually temporary files).

 

Thank you

 

 

 

 

By: lihongbing - hongbingli

RE: Error on X need to restart web application

2003-09-03 04:55

your are right. not the websever but application server remember the bad thing.for tomcat ther is a directoty named work ,it's tomcat's work directory to record some inner runtime information .

in jasper source code ,i find error souce in jrbasefill.java

static

{

//FIXME use this in some kind of a isFontAvailable method

String envfonts[] = GraphicsEnvironment.getLocalGraphicsEnvironment().getAvailableFontFamilyNames();

}

 

so may when application sever encounter a java inner error ,record it and no longer load this class.

 

you also can try to update this file,add a try-catch.