MavenPropertiesGuide

Good day,

Here is my list. Some of these are not yet on the list and some of them are already are. And I must admit that I am still not yet acquainted with some of them.

I also placed here where I got these from just in case somebody wants to know how I came up with this list and where to get more info (code-reading-wise).

Not sure though if this is the complete list (excluding plugin expressions and user-defined properties).

    *  project (from [1])
          o project.distributionManagementArtifactRepository
          o project.artifact
          o project.parent
          o project.file
          o project.artifacts
          o project.parentArtifact
          o project.pluginArtifacts
          o project.remoteArtifactRepositories
          o project.pluginArtifactRepositories
          o project.attachedArtifact
    * settings (from [2])
          o settings.offilne
          o settings.interactive
    * rootless (from [3])
          o localRepository
          o reactorProjects
    * java properties (from [4])
          o java.version
          o java.vendor
          o java.vendor.url
          o java.home
          o java.vm.specification.version
          o java.vm.specification.vendor
          o java.vm.specification.name
          o java.vm.version
          o java.vm.vendor
          o java.vm.name
          o java.specification.version
          o java.specification.vendor
          o java.specification.name
          o java.class.version
          o java.class.path
          o java.library.path
          o java.io.tmpdir
          o java.compiler
          o java.ext.dirs
          o os.name
          o os.arch
          o os.version
          o file.separator
          o path.separator
          o line.separator
          o user.name
          o user.home
          o user.dir

Thanks,
Franz 

[1] http://svn.apache.org/repos/asf/maven/components/trunk/maven-core/src/main/resources/META-INF/maven/plugin-expressions/project.paramdoc.xml
[2] http://svn.apache.org/repos/asf/maven/components/trunk/maven-core/src/main/resources/META-INF/maven/plugin-expressions/rootless.paramdoc.xml
[3] http://svn.apache.org/repos/asf/maven/components/trunk/maven-core/src/main/resources/META-INF/maven/plugin-expressions/settings.paramdoc.xml
[4] http://java.sun.com/j2se/1.4.2/docs/api/java/lang/System.html#getProperties

Is there a way to pick up the path name to the settings.xml file that might have been provided with the -s switch?

Is it possible to add a property to your pom.xml?  I mean, doing something like this:
<version>$

</version>

When you want to compile, just provide the value for the app.version via the command line.  The problem is that we have several builds for one application (local, server, ...) and for that we need multiple properties-files, to change settings according to the location we're deploying it to. 

Good day to you, Bjorn,

You might want to use your POM's dependencyManagement for that.

Cheers,
Franz

Hi Bjorn, 

Or maybe an other possibility is to use the Maven 2 profiles.
See http://altuure.blogspot.com/2006/11/maven-profiles.html for an example.

Cheers, Tjeerd 

Maybe you should explain how you can set such a property from a MOJO.
I would like to know this very much

Not sure if anyone else finds it useful (I know I did), but I have submitted a patch to plexus-utils that allows selection of properties from lists within the POM: http://jira.codehaus.org/browse/PLXUTILS-37
For example, given the following in the POM:

<project>
  ...
  <developers>
    <developer>
      <id>myUserId</id>
      <name>Jamie Burrell</name>
      <email>jamie.burrell@nospam.com</email>
      <roles>
        <role>developer</role>
      </roles>
      <timezone>0</timezone>
    </developer> 
    <developer>
      <id>herUserId</id>
      <name>Jane Doe</name>
      <email>jane.doe@nospam.com</email>
      <organization>Doe Solutions</organization>
      <roles>
        <role>developer</role>
      </roles>
      <timezone>0</timezone>
    </developer> 
  </developers>
  ...
</project>

Referencing ${project.developers.0.id} in the POM would then return "myUserId".

Not useful to everyone, but also not harmful, and allows access to all the list props on the POM (such as developers, contributors, profiles etc). I've been using it to automate directory path filtering for each developer (on *nix, the path is /home/group/userid).

Comments welcome.

Cheers, Jamie

Hi!

It's not exactly the best place to ask, but, do you know how can we declare a custom property that is a collection? Something like

  <properties>
<my.filter.value>
<items> 
<item>hello</item>
<item>world</item> 
</items>
</properties>Thaanks in advance!

Hi all,

Thanks for the list. I am wondering if their is any Maven variable that can be used to obtain date of the system, I want to use this as the folder name in which my maven builds will go in to.

 I fancy for something like  <directory>"Date"</directory> in the build tag of pom.xml.

Please guide on the same.

Regards,

Amit

Thanks for the list of the default ones! I was looking all over maven.apache.org for something like that. They should really clean this up, make sure it's complete, and then put it up.

On a related note, does anyone know if it's possible to provide a pom.xml file with a standard Java properties file and have maven read the file and set those properties accordingly?

Is it possible to know into a variable the goal launched ?

I want with a developper profile do the tests only with a maven test. So like that, the maven install will be faster. The idea is to use this variable with the skip test.

${maven.repo.local} doesn't seem to be working anymore...

how can i reference the assembly id in my descriptor file? 

<build>
        <plugins>
            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <executions>
                    <execution>
                        <id>mysql</id>
                        <phase>package</phase>
                        <goals>
                            <goal>single</goal>
                        </goals>
                       
                        <configuration>
                            <descriptors>
                                <descriptor>src/main/assemblies/descriptor.xml</descriptor>

                                <!- I want to reference the assembly id "mysql" in this descriptor.xml, how to do that ? ->
                             </descriptors>
                        [...]

                        </configuration>

                    </execution>

              </executions>

          <plugin>

     <plugins>

 thanks alot!

Since Maven 2.1, you can use build timestamp as property:

maven.build.timestamp

and configure the format:

<maven.build.timestamp.format>yyyyMMdd-HHmm</maven.build.timestamp.format>

http://maven.apache.org/guides/introduction/introduction-to-the-pom.html