27 Nov
2014
27 Nov
'14
5:20 a.m.
Having been put off writing Java components a number of times I've decided to really
tackle the problem head on. I would greatly appreciate any help in this.
I've been following the advice in
http://platform.xwiki.org/xwiki/bin/view/DevGuide/WritingComponents and I have compiled a
Jar identical to the Hello World example except that the class and method names differ,
hopefully consistently. I've placed the jar in XE_WAR_HOME/WEB-INF/lib and written a
page, which consists only of
{{velocity}}
$services.mycomponent.greet()
{{/velocity}}
The output when viewed is simple "$services.alertdb.greet()", so nothing seems
to have happened. However, if I restart Tomcat (and then wait a minute or so for XWiki to
restart) the output is "Hello", as desired.
So is a restart of Tomcat always required? This wasn't mentioned in the guide. And
since extensions can be added via the extension manager without a restart, is there a
sneaky trick to doing the same with my own components.
Also, is a restart necessary when I update the Jar, either with fixed methods or modified
interface?
27 Nov
27 Nov
8:36 a.m.
What you have in XE_WAR_HOME/WEB-INF/lib is loaded by Tomcat at
startup, there is not much XWiki can do about it.
But you can install your jar as an extension using Extension Manager
as long as it's on some supported repository (which mean a Maven
repository or XWiki repository, see
http://extensions.xwiki.org/xwiki/bin/view/Extension/Repository+Application
for this last one) and you indicate your repository in
xwiki.properties.
On Thu, Nov 27, 2014 at 5:20 AM, Bryn Jeffries
<bryn.jeffries(a)sydney.edu.au> wrote:
Having been put off writing Java components a number
of times I've decided to really tackle the problem head on. I would greatly appreciate
any help in this.
I've been following the advice in
http://platform.xwiki.org/xwiki/bin/view/DevGuide/WritingComponents and I have compiled a
Jar identical to the Hello World example except that the class and method names differ,
hopefully consistently. I've placed the jar in XE_WAR_HOME/WEB-INF/lib and written a
page, which consists only of
{{velocity}}
$services.mycomponent.greet()
{{/velocity}}
The output when viewed is simple "$services.alertdb.greet()", so nothing seems
to have happened. However, if I restart Tomcat (and then wait a minute or so for XWiki to
restart) the output is "Hello", as desired.
So is a restart of Tomcat always required? This wasn't mentioned in the guide. And
since extensions can be added via the extension manager without a restart, is there a
sneaky trick to doing the same with my own components.
Also, is a restart necessary when I update the Jar, either with fixed methods or modified
interface?
_______________________________________________
users mailing list
users(a)xwiki.org
http://lists.xwiki.org/mailman/listinfo/users
--
Thomas Mortagne
8:38 a.m.
On Thu, Nov 27, 2014 at 8:36 AM, Thomas Mortagne
<thomas.mortagne(a)xwiki.com> wrote:
What you have in XE_WAR_HOME/WEB-INF/lib is loaded by
Tomcat at
startup, there is not much XWiki can do about it.
But you can install your jar as an extension using Extension Manager
as long as it's on some supported repository (which mean a Maven
repository or XWiki repository, see
http://extensions.xwiki.org/xwiki/bin/view/Extension/Repository+Application
for this last one) and you indicate your repository in
xwiki.properties.
Note that Extension Manager is not the best fit right now to test
snapshot jars since it does not have the required special handling of
SNAPSHOT needed to update to a new version of the same SNAPSHOT
version.
On Thu, Nov 27, 2014 at 5:20 AM, Bryn Jeffries
<bryn.jeffries(a)sydney.edu.au> wrote:
--
Thomas Mortagne
Having been put off writing Java components a
number of times I've decided to really tackle the problem head on. I would greatly
appreciate any help in this.
I've been following the advice in
http://platform.xwiki.org/xwiki/bin/view/DevGuide/WritingComponents and I have compiled a
Jar identical to the Hello World example except that the class and method names differ,
hopefully consistently. I've placed the jar in XE_WAR_HOME/WEB-INF/lib and written a
page, which consists only of
{{velocity}}
$services.mycomponent.greet()
{{/velocity}}
The output when viewed is simple "$services.alertdb.greet()", so nothing seems
to have happened. However, if I restart Tomcat (and then wait a minute or so for XWiki to
restart) the output is "Hello", as desired.
So is a restart of Tomcat always required? This wasn't mentioned in the guide. And
since extensions can be added via the extension manager without a restart, is there a
sneaky trick to doing the same with my own components.
Also, is a restart necessary when I update the Jar, either with fixed methods or modified
interface?
_______________________________________________
users mailing list
users(a)xwiki.org
http://lists.xwiki.org/mailman/listinfo/users
--
Thomas Mortagne
30 Nov
30 Nov
8:11 p.m.
I wrote:
> So is a restart of Tomcat always required? This
wasn't mentioned in the guide.
> And since extensions can be added via the extension manager without a restart,
> is there a sneaky trick to doing the same with my own components.
Thomas Mortagne wrote:
What you have in XE_WAR_HOME/WEB-INF/lib is loaded by
Tomcat at
startup, there is not much XWiki can do about it.
It also seems that restarting Tomcat isn't always sufficient to update a component.
I've updated the jar file a couple of times and seen the same behaviour after the
restart.
I notice that in the Tomcat docs there is a reloadable attribute for the
org.apache.catalina.Loader interface
http://tomcat.apache.org/tomcat-7.0-doc/config/loader.html
"Set to true if you want Catalina to monitor classes in /WEB-INF/classes/ and
/WEB-INF/lib for changes, and automatically reload the web application if a change is
detected. This feature is very useful during application development, but it requires
significant runtime overhead and is not recommended for use on deployed production
applications. You can use the Manager web application, however, to trigger reloads of
deployed applications on demand."
Doesn't that mean that the corresponding XWiki class could support reloading as a
configurable option?
1 Dec
1 Dec
9:31 a.m.
On Sun, Nov 30, 2014 at 8:11 PM, Bryn Jeffries
<bryn.jeffries(a)sydney.edu.au> wrote:
I wrote:
You don't win much time by relaoding Tomcat instead of restarting it,
the purely Tomcat side is quick compared to XWiki init.
Usually the best is to test everything you can using junit (plus and
you always sleep better with a good code coverage :)) and only test a
few complex scenario hard to mock with the complete stack.
> So is a restart of Tomcat always required?
This wasn't mentioned in the guide.
> And since extensions can be added via the extension manager without a restart,
> is there a sneaky trick to doing the same with my own components.
Thomas Mortagne wrote:
What you have in XE_WAR_HOME/WEB-INF/lib is
loaded by Tomcat at
startup, there is not much XWiki can do about it.
It also seems that restarting Tomcat isn't always sufficient to update a component.
I've updated the jar file a couple of times and seen the same behaviour after the
restart.
I notice that in the Tomcat docs there is a reloadable attribute for the
org.apache.catalina.Loader interface
http://tomcat.apache.org/tomcat-7.0-doc/config/loader.html
"Set to true if you want Catalina to monitor classes in /WEB-INF/classes/ and
/WEB-INF/lib for changes, and automatically reload the web application if a change is
detected. This feature is very useful during application development, but it requires
significant runtime overhead and is not recommended for use on deployed production
applications. You can use the Manager web application, however, to trigger reloads of
deployed applications on demand."
Doesn't that mean that the corresponding XWiki class could support reloading as a
configurable option? _______________________________________________
users mailing list
users(a)xwiki.org
http://lists.xwiki.org/mailman/listinfo/users
--
Thomas Mortagne
8:53 p.m.
Thomas Mortagne wrote:
Yes, I'm coming around to thinking that's the simplest approach. I tried setting
the Context to reloadable in xwiki.xml and adding my component as a watched resource:
<Context path="/xwiki" docBase="/usr/lib/xwiki"
privileged="true"
allowLinking="true" crossContext="true"
reloadable="true">
<!-- make symlinks work in Tomcat -->
<Resources className="org.apache.naming.resources.FileDirContext"
allowLinking="true" />
<!-- allow hot reload of my component -->
<WatchedResource>/usr/lib/xwiki/WEB-INF/lib/mycomponent.jar</WatchedResource>
</Context>
This seemed to trigger a reload of the whole of XWiki, which wasn't pretty, though it
did do the job. Alas it generated a lot of errors in the log in the process, of the form:
SEVERE: The web application [/xwiki] registered the JDBC driver [org.postgresql.Driver]
but failed to unregister it when the web application was stopped.
SEVERE: The web application [/xwiki] created a ThreadLocal with key of type
[com.xpn.xwiki.store.migration.AbstractDataMigrationManager.ThreadLock] (value
[com.xpn.xwiki.store.migration.AbstractDataMigrationManager$ThreadLock@334be165]) and a
value of type [java.lang.Integer] (value [0]) but failed to remove it when the web
application was stopped.
And lots more of the above. So I won't be doing this...
Incidentally, I think I was wrong about old code persisting after a restart of Tomcat - I
reckon I just missed a step in my process.
I notice that
in the Tomcat docs there is a reloadable attribute for the
org.apache.catalina.Loader interface
[...]
Doesn't that mean that the corresponding XWiki class could support
reloading as a configurable option?
You don't win much time by relaoding Tomcat instead of restarting it,
the purely Tomcat side is quick compared to XWiki init.
Usually the best is to test everything you can using junit (plus and
you always sleep better with a good code coverage :)) and only test a
few complex scenario hard to mock with the complete stack.
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days inactive
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days old
5 comments
2 participants
participants (2)
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Bryn Jeffries -
Thomas Mortagne