NullPointerException during deployment to a Weblogic container

[gitblit]

Originally reported on Google Code with ID 199

What steps will reproduce the problem?
1.deploy gitblit.war to a weblogic server container
2.start the JVM
3.not the exception

What is the expected output? What do you see instead?
expected the ap to deploy, but the deployment failed.


What version of the product are you using? On what operating system?
1.2.1, HPUX, Java-6, Weblogic 10.3.4

Please provide any additional information below.

It appears that Giblit.java is trying to call 

SevletContext.getRealPath("/") - which returns a NULL when deployed as a war file -
as stated in the API for getRealPath():

"This method returns null
if the servlet container cannot translate the virtual path
to a real path for any reason (such as when the content is
being made available from a <code>.war</code> archive).
"

See also http://stackoverflow.com/questions/536228/why-does-getrealpath-return-null-when-deployed-with-a-war-file

This was not happening in v.1.1.0.

Stack trace:

<[ACTIVE] ExecuteThread: '0' f
or queue: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1360160594805>
<BEA-101162> <User defined liste
ner com.gitblit.GitBlit failed: java.lang.NullPointerException.
java.lang.NullPointerException
        at java.io.File.<init>(File.java:231)
        at com.gitblit.GitBlit.contextInitialized(GitBlit.java:3205)
        at com.gitblit.GitBlit.contextInitialized(GitBlit.java:3196)
        at weblogic.servlet.internal.EventsManager$FireContextListenerAction.run(EventsManager.java:481)
        at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
....

Reported by jaymeyer on 2013-02-06 16:02:03

[gitblit]

Note: the WAR deploys to JBoss 5.1 sucessfully.  PErhaps there is a deplyment option
in Weblogic that will allow this call? I will test some options.

Reported by jaymeyer on 2013-02-06 16:06:17

[gitblit]

this looks promising

http://my-java-planet.blogspot.com/2011/11/how-to-fix-weblogic-servletcontextgetre.html

Reported by jaymeyer on 2013-02-07 04:37:52

[gitblit]

adding the attached weblogic.xml worked to fix the problem.

Now the gitblit.war deploys correctly.

Can this weblogic.xml be added to the standard build? It will be ignored by all other
containers.

Reported by jaymeyer on 2013-02-07 05:03:30

---

• Attachment: weblogic.xml

[gitblit]

Yup.  Does that go in WEB-INF?

Reported by James.Moger on 2013-02-07 12:47:14

[gitblit]

yes, WEB-INF.  
i.e. same dir as the web.xml

Reported by jaymeyer on 2013-02-07 13:17:04

[gitblit]

Reported by James.Moger on 2013-02-13 13:07:09

• Status changed: Accepted
• Labels added: Milestone-1.3.0

[gitblit]

Deployment as WAR file isn't working in Tomcat6, too (gitblit 1.2.1, Win2k3, Java-6,
Tomcat 6.0.33). The stacktrace is similar:

SEVERE: Exception sending context initialized event to listener instance of class com.gitblit.GitBlit
java.lang.NullPointerException
    at java.io.File.<init>(File.java:222)
    at com.gitblit.GitBlit.contextInitialized(GitBlit.java:3205)
    at com.gitblit.GitBlit.contextInitialized(GitBlit.java:3196)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4206)
    at org.apache.catalina.core.StandardContext.start(StandardContext.java:4705)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:799)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:779)
...

It used to work with gitblit 1.2.0, but fails in 1.2.1. You'd better get rid of the
getRealPath() there...

Reported by matthias.bauer.drs@infineon.com on 2013-02-28 12:31:25

[gitblit]

I agree, it is time to change my strategy for loading those resources.

Reported by James.Moger on 2013-02-28 13:02:17

[gitblit]

I have commited the weblogic.xml file to master.

I also reviewed WAR deployment on Tomcat 6.0.32 and it works as expected.  To be fair
I tested 1.3.0-SNAPSHOT which has slightly revised context initialization code.

Reported by James.Moger on 2013-03-29 12:48:59

• Status changed: Queued

[gitblit]

Hm, sorry for the delay. I've been busy with other things. And setting up and verifying
my test environment took some time.

However, I've just tested with b9aa9c36981. It didn't work unfortunately:

java.lang.NullPointerException
    at java.io.File.<init>(File.java:222)
    at com.gitblit.GitBlit.contextInitialized(GitBlit.java:3282)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4206)

If it works for you, there might be "specialties" in our Tomcat config involved. No
clue, what exactly. 

Standard practice with Tomcat seems to be that WAR files are deployed by dropping them
in Tomcats webapp folder. But for maintenance reasons we're doing it a bit different:
We're keeping the WAR file in a separate folder and configure everything in a context
descriptor file in conf/Catalina/localhost/. Something like this ("gitblit-test.xml"):

<?xml version='1.0' encoding='utf-8'?>
<Context path="/gitblit-test" docBase="C:/Path/To/War/gitblit/gitblit-1.3.0-SNAPSHOT.war">
  <Parameter name="baseFolder" value="D:/Path/To/Data/gitblit-test" override="false"/>
</Context>

In v1.2.0 had a whole bunch of <Parameter/> statements there to override the defaults
in web.xml (from w/i the WAR). That worked pretty well. Starting with 1.2.1 setting
the baseFolder and providing a valid gitblit.properties file there should have been
sufficient...

So with that in mind I tweaked the contextInitialized() function a bit to handle the
NPs correctly (see attached patch). This would solve the case for me. The patch isn't
perfect, though: Copying the default config to the basePath won't work this way. One
would have to use ServletContext.getResourcePaths() to get the names and ServletContext.getResourceAsStream()
to retrieve the content.

Reported by matthias.bauer.drs@infineon.com on 2013-05-06 17:58:09

---

• Attachment: 0001-Fix-NPE-during-context-init-in-WAR-deployment.patch