You are viewing a plain text version of this content. The canonical link for it is here.

Posted to users@tapestry.apache.org by Rui Pacheco <ru...@gmail.com> on 2006/05/12 17:31:42 UTC

Creating a custom component

Hi all again

I am trying to create a custom component for my menu, header and footer. I
created a Menu.html whose content is a simple html table.
I created a .jwc file in my WEB-INF directory with the following content:

<component-specification class="org.apache.tapestry.BaseComponent"
allow-body="no" allow-informal-parameters="no">
</component>

But when I deploy my application, Tomcat starts dumping this error in an
endless loop:

May 12, 2006 4:29:41 PM
org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessorprocessChildren
SEVERE: Exception invoking periodic operation:
java.lang.NullPointerException
...

I am following these pages on creating custom components, but I cant find
out what is it I'm doing wrong:
http://jakarta.apache.org/tapestry/UsersGuide/components.html
http://jakarta.apache.org/tapestry/tapestry/ComponentReference/RenderBlock.html#Example
-- 
Cumprimentos,
Rui Pacheco

Re: Creating a custom component

Posted by Bryan Lewis <br...@maine.rr.com>.

It looks like something unrelated to your custom component or to
Tapestry at all.  The stack trace is entirely inside the Tomcat code. 
I'd try a clean rebuild of the app and restarting Tomcat, deleting the
old webapps and work trees to make sure it's starting with a clean
slate.  If that didn't fix it, I'd deploy an earlier version of the app
to see whether it was really my latest change that caused it.

What might that "periodic operation" be?


Rui Pacheco wrote:

> Tomcat prints this:
>
> May 12, 2006 5:03:52 PM
> org.apache.catalina.startup.HostConfigcheckResources
> INFO: Undeploying context [/universal-agc]
> May 12, 2006 5:03:52 PM
> org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessorprocessChildren
>
> SEVERE: Exception invoking periodic operation:
> java.lang.NullPointerException
>        at org.apache.catalina.core.ContainerBase.removeChild(
> ContainerBase.java:883)
>        at org.apache.catalina.startup.HostConfig.checkResources(
> HostConfig.java:978)
>        at org.apache.catalina.startup.HostConfig.check(HostConfig.java
> :1172)
>        at org.apache.catalina.startup.HostConfig.lifecycleEvent(
> HostConfig.java:292)
>        at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(
> LifecycleSupport.java:119)
>        at org.apache.catalina.core.ContainerBase.backgroundProcess(
> ContainerBase.java:1305)
>        at
> org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren
>
> (ContainerBase.java:1569)
>        at
> org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren
>
> (ContainerBase.java:1578)
>        at
> org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(
> ContainerBase.java:1558)
>        at java.lang.Thread.run(Thread.java:595)
>
>
> In an endless cycle.
>
> On 5/12/06, Paul Cantrell <ca...@pobox.com> wrote:
>
>>
>> A complete stack track trace might help; "NullPointerException" by
>> itself doesn't say much....
>>
>> On May 12, 2006, at 10:31 AM, Rui Pacheco wrote:
>>
>> > Hi all again
>> >
>> > I am trying to create a custom component for my menu, header and
>> > footer. I
>> > created a Menu.html whose content is a simple html table.
>> > I created a .jwc file in my WEB-INF directory with the following
>> > content:
>> >
>> > <component-specification class="org.apache.tapestry.BaseComponent"
>> > allow-body="no" allow-informal-parameters="no">
>> > </component>
>> >
>> > But when I deploy my application, Tomcat starts dumping this error
>> > in an
>> > endless loop:
>> >
>> > May 12, 2006 4:29:41 PM
>> > org.apache.catalina.core.ContainerBase
>> > $ContainerBackgroundProcessorprocessChildren
>> > SEVERE: Exception invoking periodic operation:
>> > java.lang.NullPointerException
>> > ...
>> >
>> > I am following these pages on creating custom components, but I
>> > cant find
>> > out what is it I'm doing wrong:
>> > http://jakarta.apache.org/tapestry/UsersGuide/components.html
>> > http://jakarta.apache.org/tapestry/tapestry/ComponentReference/
>> > RenderBlock.html#Example
>> > --
>> > Cumprimentos,
>> > Rui Pacheco
>>
>> _________________________________________________________________
>> Piano music podcast: http://inthehands.com
>> Other interesting stuff: http://innig.net
>>
>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
>> For additional commands, e-mail: users-help@tapestry.apache.org
>>
>>
>
>


---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
For additional commands, e-mail: users-help@tapestry.apache.org

Re: Creating a custom component

Posted by Rui Pacheco <ru...@gmail.com>.

Tomcat prints this:

May 12, 2006 5:03:52 PM org.apache.catalina.startup.HostConfigcheckResources
INFO: Undeploying context [/universal-agc]
May 12, 2006 5:03:52 PM
org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessorprocessChildren
SEVERE: Exception invoking periodic operation:
java.lang.NullPointerException
        at org.apache.catalina.core.ContainerBase.removeChild(
ContainerBase.java:883)
        at org.apache.catalina.startup.HostConfig.checkResources(
HostConfig.java:978)
        at org.apache.catalina.startup.HostConfig.check(HostConfig.java
:1172)
        at org.apache.catalina.startup.HostConfig.lifecycleEvent(
HostConfig.java:292)
        at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(
LifecycleSupport.java:119)
        at org.apache.catalina.core.ContainerBase.backgroundProcess(
ContainerBase.java:1305)
        at
org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren
(ContainerBase.java:1569)
        at
org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren
(ContainerBase.java:1578)
        at
org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(
ContainerBase.java:1558)
        at java.lang.Thread.run(Thread.java:595)


In an endless cycle.

On 5/12/06, Paul Cantrell <ca...@pobox.com> wrote:
>
> A complete stack track trace might help; "NullPointerException" by
> itself doesn't say much....
>
> On May 12, 2006, at 10:31 AM, Rui Pacheco wrote:
>
> > Hi all again
> >
> > I am trying to create a custom component for my menu, header and
> > footer. I
> > created a Menu.html whose content is a simple html table.
> > I created a .jwc file in my WEB-INF directory with the following
> > content:
> >
> > <component-specification class="org.apache.tapestry.BaseComponent"
> > allow-body="no" allow-informal-parameters="no">
> > </component>
> >
> > But when I deploy my application, Tomcat starts dumping this error
> > in an
> > endless loop:
> >
> > May 12, 2006 4:29:41 PM
> > org.apache.catalina.core.ContainerBase
> > $ContainerBackgroundProcessorprocessChildren
> > SEVERE: Exception invoking periodic operation:
> > java.lang.NullPointerException
> > ...
> >
> > I am following these pages on creating custom components, but I
> > cant find
> > out what is it I'm doing wrong:
> > http://jakarta.apache.org/tapestry/UsersGuide/components.html
> > http://jakarta.apache.org/tapestry/tapestry/ComponentReference/
> > RenderBlock.html#Example
> > --
> > Cumprimentos,
> > Rui Pacheco
>
> _________________________________________________________________
> Piano music podcast: http://inthehands.com
> Other interesting stuff: http://innig.net
>
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
> For additional commands, e-mail: users-help@tapestry.apache.org
>
>


-- 
Cumprimentos,
Rui Pacheco

Re: Creating a custom component

Posted by Paul Cantrell <ca...@pobox.com>.

A complete stack track trace might help; "NullPointerException" by  
itself doesn't say much....

On May 12, 2006, at 10:31 AM, Rui Pacheco wrote:

> Hi all again
>
> I am trying to create a custom component for my menu, header and  
> footer. I
> created a Menu.html whose content is a simple html table.
> I created a .jwc file in my WEB-INF directory with the following  
> content:
>
> <component-specification class="org.apache.tapestry.BaseComponent"
> allow-body="no" allow-informal-parameters="no">
> </component>
>
> But when I deploy my application, Tomcat starts dumping this error  
> in an
> endless loop:
>
> May 12, 2006 4:29:41 PM
> org.apache.catalina.core.ContainerBase 
> $ContainerBackgroundProcessorprocessChildren
> SEVERE: Exception invoking periodic operation:
> java.lang.NullPointerException
> ...
>
> I am following these pages on creating custom components, but I  
> cant find
> out what is it I'm doing wrong:
> http://jakarta.apache.org/tapestry/UsersGuide/components.html
> http://jakarta.apache.org/tapestry/tapestry/ComponentReference/ 
> RenderBlock.html#Example
> -- 
> Cumprimentos,
> Rui Pacheco

_________________________________________________________________
Piano music podcast: http://inthehands.com
Other interesting stuff: http://innig.net



---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscribe@tapestry.apache.org
For additional commands, e-mail: users-help@tapestry.apache.org