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Posted to users@maven.apache.org by Stefano Fornari <st...@gmail.com> on 2006/05/23 11:55:40 UTC

NPE using JavaCC

Hi All,
still struggling with JavaCC and Maven. I have the following pom:

<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <artifactId>funambol-framework</artifactId>
    <groupId>com.funambol</groupId>
    <version>3.0-SNAPSHOT</version>
    <name>Funambol Framework</name>
    <dependencies>
        <!--
            External dependencies
        -->
        <dependency>
            <artifactId>commons-lang</artifactId>
            <groupId>commons-lang</groupId>
            <version>2.0</version>
        </dependency>

        <dependency>
            <artifactId>servlet-api</artifactId>
            <groupId>javax.servlet</groupId>
            <version>2.4</version>
        </dependency>

        <dependency>
            <artifactId>p6spy</artifactId>
            <groupId>p6spy</groupId>
            <version>1.3</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>net.java.dev.javacc</groupId>
                <artifactId>javacc</artifactId>
                <version>4.0</version>
                <configuration>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

And when I run mvn compile, I get a Null Pointer Exception:

[INFO] Scanning for projects...
[INFO] ----------------------------------------------------------------------------
[INFO] Building Funambol Framework
[INFO]    task-segment: [compile]
[INFO] ----------------------------------------------------------------------------
Downloading: http://repo1.maven.org/maven2/net/java/dev/javacc/javacc/4.0/javacc-4.0.pom
897b downloaded
Downloading: http://repo1.maven.org/maven2/net/java/dev/javacc/javacc/4.0/javacc-4.0.jar
267K downloaded
[INFO] ------------------------------------------------------------------------
[ERROR] FATAL ERROR
[INFO] ------------------------------------------------------------------------
[INFO] null
[INFO] ------------------------------------------------------------------------
[INFO] Trace
java.lang.NullPointerException
        at org.apache.maven.plugin.DefaultPluginManager.addPlugin(DefaultPluginManager.java:292)
        at org.apache.maven.plugin.DefaultPluginManager.verifyVersionedPlugin(DefaultPluginManager.java:198)
        at org.apache.maven.plugin.DefaultPluginManager.verifyPlugin(DefaultPluginManager.java:163)
[...]

Has anyone a clue?

Thanks in advance.

Stefano


-- 
Stefano Fornari - Funambol Chief Architect / Funambol CTO
=======================================================
Home:
http://www.funambol.org

Documents:
http://www.funambol.org/documentation/documents.html

FAQ:
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Re: NPE using JavaCC

Posted by Stefano Fornari <st...@gmail.com>.
Hey Tim!
you are great! Thanks a lot for your help, it worked. I hope I'll have
the opportunity to pay the bill in some way ;)

Ste

On 5/23/06, Tim Kettler <ti...@udo.edu> wrote:
> (Almost) all plugins have a groupId of either 'org.apache.maven.plugins' or
> 'org.codehaus.mojo' so everything else looks suspicious until proved otherwise :-)
>
> Have you tried the links from my first mail? I have checked them before posting and they
> did work for me.
>
> Just to be sure: In case the links don't work for you I paste this sample configuration
> snippet from the first link:
>
> <plugin>
>    <groupId>org.codehaus.mojo</groupId>
>    <artifactId>javacc-maven-plugin</artifactId>
>    <executions>
>      <execution>
>        <goals>
>          <goal>javacc</goal>
>        </goals>
>      </execution>
>    </executions>
> </plugin>
>
> -Tim
>
>


-- 
Stefano Fornari - Funambol Chief Architect / Funambol CTO
=======================================================
Home:
http://www.funambol.org

Documents:
http://www.funambol.org/documentation/documents.html

FAQ:
http://www.funambol.org/support/faq.html

WIKI:
https://wiki.objectweb.org/sync4j/

Mailinglist archives:
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Re: NPE using JavaCC

Posted by Tim Kettler <ti...@udo.edu>.
(Almost) all plugins have a groupId of either 'org.apache.maven.plugins' or 
'org.codehaus.mojo' so everything else looks suspicious until proved otherwise :-)

Have you tried the links from my first mail? I have checked them before posting and they 
did work for me.

Just to be sure: In case the links don't work for you I paste this sample configuration 
snippet from the first link:

<plugin>
   <groupId>org.codehaus.mojo</groupId>
   <artifactId>javacc-maven-plugin</artifactId>
   <executions>
     <execution>
       <goals>
         <goal>javacc</goal>
       </goals>
     </execution>
   </executions>
</plugin>

-Tim


Stefano Fornari schrieb:
> That's a great catch!
> I actually assumed I could use it as plugin, because when I ran mvn
> javacc:javacc, I get:
> 
> INFO] Scanning for projects...
> [INFO] Searching repository for plugin with prefix: 'javacc'.
> [INFO] 
> ---------------------------------------------------------------------------- 
> 
> [INFO] Building Funambol Framework
> [INFO]    task-segment: [javacc:javacc]
> [INFO] 
> ---------------------------------------------------------------------------- 
> 
> Downloading: http://repo1.maven.org/maven2/javacc/javacc/3.2/javacc-3.2.pom
> 281b downloaded
> [WARNING] While downloading javacc:javacc:3.2
>  This artifact has been relocated to net.java.dev.javacc:javacc:3.2.
> 
> 
> Downloading: 
> http://repo1.maven.org/maven2/net/java/dev/javacc/javacc/3.2/javacc-3.2.pom
> 162b downloaded
> Downloading: 
> http://repo1.maven.org/maven2/net/java/dev/javacc/javacc/3.2/javacc-3.2.jar
> 369K downloaded
> 
> so I assumed it downloaded the plug-in as well. It looks like it was a
> wrong assumption.
> 
> Now I would like that maven would invoke the javacc source generation
> without calling javacc:javacc. I guess I have to specify some plug in
> or something, because now it does not work. Sorry to bother you, but
> the codehous site is down and I could not find any information
> googleling....
> 
> Stefano
> 
> On 5/23/06, Tim Kettler <ti...@udo.edu> wrote:
>>
>> The pom of the artifact you are referencing in your plugin definition
>> (http://repo.mergere.com/maven2/net/java/dev/javacc/javacc/4.0/javacc-4.0.pom) 
>> has a
>> packaging of type 'jar' and not 'maven-plugin' as it should if it 
>> really is a plugin. I
>> think this is just javacc itself.
>>
>> Or does your javacc-plugin come from an other repository?
>>
>> -Tim
>>
>> Stefano Fornari schrieb:
>> > Hi Tim,
>> > I am sure it exists, otherwise I get an error that the plugin cannot
>> > be found. The weird thing is that the NPE is in the maven code, not
>> > int the plug-in code.... but I am pretty sure it is a configuration
>> > problem (actually, the fact I get a NPE is probably a maven bug, but
>> > due to a not correct pom).
>> >
>> > Thanks for your reply.
>> >
>> > Stefano
>> >
>> > On 5/23/06, Tim Kettler <ti...@udo.edu> wrote:
>> >> Stefano Fornari schrieb:
>> >> > Hi All,
>> >> > still struggling with JavaCC and Maven. I have the following pom:
>> >> >
>> >> > <project xmlns="http://maven.apache.org/POM/4.0.0"
>> >> > xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
>> >> >  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
>> >> > http://maven.apache.org/maven-v4_0_0.xsd">
>> >> >    <modelVersion>4.0.0</modelVersion>
>> >> >    <artifactId>funambol-framework</artifactId>
>> >> >    <groupId>com.funambol</groupId>
>> >> >    <version>3.0-SNAPSHOT</version>
>> >> >    <name>Funambol Framework</name>
>> >> >    <dependencies>
>> >>
>> >> [...]
>> >>
>> >> >    <build>
>> >> >        <plugins>
>> >> >            <plugin>
>> >> >                <groupId>net.java.dev.javacc</groupId>
>> >> >                <artifactId>javacc</artifactId>
>> >> >                <version>4.0</version>
>> >> >                <configuration>
>> >> >                </configuration>
>> >> >            </plugin>
>> >> >        </plugins>
>> >> >    </build>
>> >> >
>> >> > </project>
>> >>
>> >> Are your sure the plugin with the artifact id 'javacc' with the
>> >> groupid 'net.java.dev'
>> >> exists? I only know the javacc plugin from the mojo project over at
>> >> codehaus.org.
>> >>
>> >> The mojo homepage is currently down due to the codehaus outage but you
>> >> can have a look at
>> >> the apt sources of the javacc-plugin site here:
>> >> 
>> http://svn.codehaus.org/mojo/trunk/mojo/javacc-maven-plugin/src/site/apt/index.apt. 
>>
>> >> It's
>> >> quite readable.
>> >>
>> >> Or you can checkout the plugin sources via svn from here:
>> >> http://svn.codehaus.org/mojo/trunk/mojo/javacc-maven-plugin/. and
>> >> build the site locally
>> >> with 'mvn site:site'.
>> >>
>> >> >
>> >> >
>> >> > [...]
>> >> >
>> >> > Has anyone a clue?
>> >> >
>> >> > Thanks in advance.
>> >> >
>> >> > Stefano
>> >> >
>> >> >
>> >>
>> >> Hope this help
>> >> -Tim
>> >>
>> >> ---------------------------------------------------------------------
>> >> To unsubscribe, e-mail: users-unsubscribe@maven.apache.org
>> >> For additional commands, e-mail: users-help@maven.apache.org
>> >>
>> >>
>> >
>> >
>>
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@maven.apache.org
>> For additional commands, e-mail: users-help@maven.apache.org
>>
>>
> 
> 


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Re: NPE using JavaCC

Posted by Stefano Fornari <st...@gmail.com>.
That's a great catch!
I actually assumed I could use it as plugin, because when I ran mvn
javacc:javacc, I get:

INFO] Scanning for projects...
[INFO] Searching repository for plugin with prefix: 'javacc'.
[INFO] ----------------------------------------------------------------------------
[INFO] Building Funambol Framework
[INFO]    task-segment: [javacc:javacc]
[INFO] ----------------------------------------------------------------------------
Downloading: http://repo1.maven.org/maven2/javacc/javacc/3.2/javacc-3.2.pom
281b downloaded
[WARNING] While downloading javacc:javacc:3.2
  This artifact has been relocated to net.java.dev.javacc:javacc:3.2.


Downloading: http://repo1.maven.org/maven2/net/java/dev/javacc/javacc/3.2/javacc-3.2.pom
162b downloaded
Downloading: http://repo1.maven.org/maven2/net/java/dev/javacc/javacc/3.2/javacc-3.2.jar
369K downloaded

so I assumed it downloaded the plug-in as well. It looks like it was a
wrong assumption.

Now I would like that maven would invoke the javacc source generation
without calling javacc:javacc. I guess I have to specify some plug in
or something, because now it does not work. Sorry to bother you, but
the codehous site is down and I could not find any information
googleling....

Stefano

On 5/23/06, Tim Kettler <ti...@udo.edu> wrote:
>
> The pom of the artifact you are referencing in your plugin definition
> (http://repo.mergere.com/maven2/net/java/dev/javacc/javacc/4.0/javacc-4.0.pom) has a
> packaging of type 'jar' and not 'maven-plugin' as it should if it really is a plugin. I
> think this is just javacc itself.
>
> Or does your javacc-plugin come from an other repository?
>
> -Tim
>
> Stefano Fornari schrieb:
> > Hi Tim,
> > I am sure it exists, otherwise I get an error that the plugin cannot
> > be found. The weird thing is that the NPE is in the maven code, not
> > int the plug-in code.... but I am pretty sure it is a configuration
> > problem (actually, the fact I get a NPE is probably a maven bug, but
> > due to a not correct pom).
> >
> > Thanks for your reply.
> >
> > Stefano
> >
> > On 5/23/06, Tim Kettler <ti...@udo.edu> wrote:
> >> Stefano Fornari schrieb:
> >> > Hi All,
> >> > still struggling with JavaCC and Maven. I have the following pom:
> >> >
> >> > <project xmlns="http://maven.apache.org/POM/4.0.0"
> >> > xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
> >> >  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
> >> > http://maven.apache.org/maven-v4_0_0.xsd">
> >> >    <modelVersion>4.0.0</modelVersion>
> >> >    <artifactId>funambol-framework</artifactId>
> >> >    <groupId>com.funambol</groupId>
> >> >    <version>3.0-SNAPSHOT</version>
> >> >    <name>Funambol Framework</name>
> >> >    <dependencies>
> >>
> >> [...]
> >>
> >> >    <build>
> >> >        <plugins>
> >> >            <plugin>
> >> >                <groupId>net.java.dev.javacc</groupId>
> >> >                <artifactId>javacc</artifactId>
> >> >                <version>4.0</version>
> >> >                <configuration>
> >> >                </configuration>
> >> >            </plugin>
> >> >        </plugins>
> >> >    </build>
> >> >
> >> > </project>
> >>
> >> Are your sure the plugin with the artifact id 'javacc' with the
> >> groupid 'net.java.dev'
> >> exists? I only know the javacc plugin from the mojo project over at
> >> codehaus.org.
> >>
> >> The mojo homepage is currently down due to the codehaus outage but you
> >> can have a look at
> >> the apt sources of the javacc-plugin site here:
> >> http://svn.codehaus.org/mojo/trunk/mojo/javacc-maven-plugin/src/site/apt/index.apt.
> >> It's
> >> quite readable.
> >>
> >> Or you can checkout the plugin sources via svn from here:
> >> http://svn.codehaus.org/mojo/trunk/mojo/javacc-maven-plugin/. and
> >> build the site locally
> >> with 'mvn site:site'.
> >>
> >> >
> >> >
> >> > [...]
> >> >
> >> > Has anyone a clue?
> >> >
> >> > Thanks in advance.
> >> >
> >> > Stefano
> >> >
> >> >
> >>
> >> Hope this help
> >> -Tim
> >>
> >> ---------------------------------------------------------------------
> >> To unsubscribe, e-mail: users-unsubscribe@maven.apache.org
> >> For additional commands, e-mail: users-help@maven.apache.org
> >>
> >>
> >
> >
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@maven.apache.org
> For additional commands, e-mail: users-help@maven.apache.org
>
>


-- 
Stefano Fornari - Funambol Chief Architect / Funambol CTO
=======================================================
Home:
http://www.funambol.org

Documents:
http://www.funambol.org/documentation/documents.html

FAQ:
http://www.funambol.org/support/faq.html

WIKI:
https://wiki.objectweb.org/sync4j/

Mailinglist archives:
http://groups.yahoo.com/group/Sync4j (login required)
http://sourceforge.net/mailarchive/forum.php?forum_id=215

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Re: NPE using JavaCC

Posted by Tim Kettler <ti...@udo.edu>.
The pom of the artifact you are referencing in your plugin definition 
(http://repo.mergere.com/maven2/net/java/dev/javacc/javacc/4.0/javacc-4.0.pom) has a 
packaging of type 'jar' and not 'maven-plugin' as it should if it really is a plugin. I 
think this is just javacc itself.

Or does your javacc-plugin come from an other repository?

-Tim

Stefano Fornari schrieb:
> Hi Tim,
> I am sure it exists, otherwise I get an error that the plugin cannot
> be found. The weird thing is that the NPE is in the maven code, not
> int the plug-in code.... but I am pretty sure it is a configuration
> problem (actually, the fact I get a NPE is probably a maven bug, but
> due to a not correct pom).
> 
> Thanks for your reply.
> 
> Stefano
> 
> On 5/23/06, Tim Kettler <ti...@udo.edu> wrote:
>> Stefano Fornari schrieb:
>> > Hi All,
>> > still struggling with JavaCC and Maven. I have the following pom:
>> >
>> > <project xmlns="http://maven.apache.org/POM/4.0.0"
>> > xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
>> >  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
>> > http://maven.apache.org/maven-v4_0_0.xsd">
>> >    <modelVersion>4.0.0</modelVersion>
>> >    <artifactId>funambol-framework</artifactId>
>> >    <groupId>com.funambol</groupId>
>> >    <version>3.0-SNAPSHOT</version>
>> >    <name>Funambol Framework</name>
>> >    <dependencies>
>>
>> [...]
>>
>> >    <build>
>> >        <plugins>
>> >            <plugin>
>> >                <groupId>net.java.dev.javacc</groupId>
>> >                <artifactId>javacc</artifactId>
>> >                <version>4.0</version>
>> >                <configuration>
>> >                </configuration>
>> >            </plugin>
>> >        </plugins>
>> >    </build>
>> >
>> > </project>
>>
>> Are your sure the plugin with the artifact id 'javacc' with the 
>> groupid 'net.java.dev'
>> exists? I only know the javacc plugin from the mojo project over at 
>> codehaus.org.
>>
>> The mojo homepage is currently down due to the codehaus outage but you 
>> can have a look at
>> the apt sources of the javacc-plugin site here:
>> http://svn.codehaus.org/mojo/trunk/mojo/javacc-maven-plugin/src/site/apt/index.apt. 
>> It's
>> quite readable.
>>
>> Or you can checkout the plugin sources via svn from here:
>> http://svn.codehaus.org/mojo/trunk/mojo/javacc-maven-plugin/. and 
>> build the site locally
>> with 'mvn site:site'.
>>
>> >
>> >
>> > [...]
>> >
>> > Has anyone a clue?
>> >
>> > Thanks in advance.
>> >
>> > Stefano
>> >
>> >
>>
>> Hope this help
>> -Tim
>>
>> ---------------------------------------------------------------------
>> To unsubscribe, e-mail: users-unsubscribe@maven.apache.org
>> For additional commands, e-mail: users-help@maven.apache.org
>>
>>
> 
> 


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Re: NPE using JavaCC

Posted by Stefano Fornari <st...@gmail.com>.
Hi Tim,
I am sure it exists, otherwise I get an error that the plugin cannot
be found. The weird thing is that the NPE is in the maven code, not
int the plug-in code.... but I am pretty sure it is a configuration
problem (actually, the fact I get a NPE is probably a maven bug, but
due to a not correct pom).

Thanks for your reply.

Stefano

On 5/23/06, Tim Kettler <ti...@udo.edu> wrote:
> Stefano Fornari schrieb:
> > Hi All,
> > still struggling with JavaCC and Maven. I have the following pom:
> >
> > <project xmlns="http://maven.apache.org/POM/4.0.0"
> > xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
> >  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
> > http://maven.apache.org/maven-v4_0_0.xsd">
> >    <modelVersion>4.0.0</modelVersion>
> >    <artifactId>funambol-framework</artifactId>
> >    <groupId>com.funambol</groupId>
> >    <version>3.0-SNAPSHOT</version>
> >    <name>Funambol Framework</name>
> >    <dependencies>
>
> [...]
>
> >    <build>
> >        <plugins>
> >            <plugin>
> >                <groupId>net.java.dev.javacc</groupId>
> >                <artifactId>javacc</artifactId>
> >                <version>4.0</version>
> >                <configuration>
> >                </configuration>
> >            </plugin>
> >        </plugins>
> >    </build>
> >
> > </project>
>
> Are your sure the plugin with the artifact id 'javacc' with the groupid 'net.java.dev'
> exists? I only know the javacc plugin from the mojo project over at codehaus.org.
>
> The mojo homepage is currently down due to the codehaus outage but you can have a look at
> the apt sources of the javacc-plugin site here:
> http://svn.codehaus.org/mojo/trunk/mojo/javacc-maven-plugin/src/site/apt/index.apt. It's
> quite readable.
>
> Or you can checkout the plugin sources via svn from here:
> http://svn.codehaus.org/mojo/trunk/mojo/javacc-maven-plugin/. and build the site locally
> with 'mvn site:site'.
>
> >
> >
> > [...]
> >
> > Has anyone a clue?
> >
> > Thanks in advance.
> >
> > Stefano
> >
> >
>
> Hope this help
> -Tim
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@maven.apache.org
> For additional commands, e-mail: users-help@maven.apache.org
>
>


-- 
Stefano Fornari - Funambol Chief Architect / Funambol CTO
=======================================================
Home:
http://www.funambol.org

Documents:
http://www.funambol.org/documentation/documents.html

FAQ:
http://www.funambol.org/support/faq.html

WIKI:
https://wiki.objectweb.org/sync4j/

Mailinglist archives:
http://groups.yahoo.com/group/Sync4j (login required)
http://sourceforge.net/mailarchive/forum.php?forum_id=215

---------------------------------------------------------------------
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Re: NPE using JavaCC

Posted by Tim Kettler <ti...@udo.edu>.
Stefano Fornari schrieb:
> Hi All,
> still struggling with JavaCC and Maven. I have the following pom:
> 
> <project xmlns="http://maven.apache.org/POM/4.0.0"
> xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
>  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
> http://maven.apache.org/maven-v4_0_0.xsd">
>    <modelVersion>4.0.0</modelVersion>
>    <artifactId>funambol-framework</artifactId>
>    <groupId>com.funambol</groupId>
>    <version>3.0-SNAPSHOT</version>
>    <name>Funambol Framework</name>
>    <dependencies>

[...]

>    <build>
>        <plugins>
>            <plugin>
>                <groupId>net.java.dev.javacc</groupId>
>                <artifactId>javacc</artifactId>
>                <version>4.0</version>
>                <configuration>
>                </configuration>
>            </plugin>
>        </plugins>
>    </build>
> 
> </project>

Are your sure the plugin with the artifact id 'javacc' with the groupid 'net.java.dev' 
exists? I only know the javacc plugin from the mojo project over at codehaus.org.

The mojo homepage is currently down due to the codehaus outage but you can have a look at 
the apt sources of the javacc-plugin site here: 
http://svn.codehaus.org/mojo/trunk/mojo/javacc-maven-plugin/src/site/apt/index.apt. It's 
quite readable.

Or you can checkout the plugin sources via svn from here: 
http://svn.codehaus.org/mojo/trunk/mojo/javacc-maven-plugin/. and build the site locally 
with 'mvn site:site'.

> 
> 
> [...]
> 
> Has anyone a clue?
> 
> Thanks in advance.
> 
> Stefano
> 
> 

Hope this help
-Tim

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