After creating a jar with shade plugin, where I shaded a certain dependency, the reduced-dependencies.pom is generated and I would like to consume it in a different project.
I can't understand how this can be done, as ONLY the complete original pom gets to be installed (and later on deployed) to my .m2 repo.
I have read and could not find my answer here, here (where OrangeDog asked it inside the comments and wasn't answered) and here.
How can I use the reduced-pom instead of the original pom in a different project ???
After some farther testing it seemed that the problem was found:
if you use the <shadedArtifactAttached>true</shadedArtifactAttached> option in the shade plugin configuration then the shaded artifact is added near the original (non-shaded) artifact, and the original (non-shaded) artifact is the one that is being installed to .m2 along with the (non-shaded) pom.
In case not using this configuration (which is by default false), then the shade plugin behaves as expected:
there is only one artifact - the shade artifact - and it, along with its reduced-dependencies.pom gets to be uploaded to .m2, as expected.
Related
I'm currently facing an issue with the execution of my MUnit tests using the command line.
I'm facing a problem of "duplicate project artifact assignment" Using version 1.2 of mule-domain-maven-plugin that was fixed here with version 1.3. Removing this line of code causes FileNotFoundException on mule-domain-config.xml when running my MUnit.
After decompiling the code, I can see that 1.2 (which works with my MUnits), has 2 lines of code :
this.projectHelper.attachArtifact(this.project, "zip", domain);
this.project.getArtifact().setFile(domain);
I can see that 1.3 has only this line :
this.projectHelper.attachArtifact(this.project, "zip", domain);
Does anybody know the difference between this.projectHelper.attachArtifact(this.project, "zip", domain); and this.project.getArtifact().setFile(domain); and how to resolve this issue?
The difference is the same as the difference between the main artifact and attached artifacts.
First of all, an artifact is, put simply, an object containing the Maven coordinates pointing to it (group id / artifact id / version / classifier / type), a repository where to resolve it or where it was resolved, and a file, which is the actual concrete file to use / download / upload.
Except for POM projects, a Maven project generates a single main artifact. It depends on its packaging; for example a project with a packaging of jar will create a main JAR artifact whose file contains all the classes of your project, and a project with a packaging of war will create the web application. Furthermore, the project itself is tied to its POM file; this means that a project, not only has a file for its main artifact, but also has reference to the POM file that created it. It is only for projects of packaging pom that no main artifact will be created; this is because such projects are parent or aggregator projects, containing build logic to be shared between multiple projects, but they do not produce a main deliverable.
In addition to this, a project has attached, or secondary, artifacts. They correspond to additional artifacts that are also generated during the build of a project, and differ from the main one by their classifier and/or type, and, naturally, their actual file. Those additional artifacts are installed and deployed alongside the main one. As an example, a typical project of packaging jar would also generate its Javadoc and Sources as a JAR file as attached artifacts having the classifier javadoc and sources. It follows that a project of packaging pom can only have attached artifacts, since it has no main artifact. Finally, it is perfectly allowed to have a project without attached artifacts; only the main one (or none at all in case of a pom project) would get deployed.
Inside a Maven plugin, all those considerations comes down to the following:
The main artifact of a project is retrieved with project.getArtifact(), as an Artifact.
project.getArtifact().setFile(...) sets the actual file of the main artifact of the project. Again, for a project of packaging jar, this would be the actual JAR file that was generated on-disk. Concrete example: it is what the Maven JAR plugin does.
The MavenProjectHelper component is used to attach artifacts to the project. projectHelper.attachArtifact(project, "zip", file); would attach an artifact of type ZIP to the given project, with no classifier, and whose file is the given file. There is an overload to attach an artifact with a classifier. Concrete example: it is what the Maven Assembly Plugin does when it is configured to attach the artifacts it produces.
project.setFile(file) sets the POM file of the Maven project that created it.
To give examples, we can consider the artifacts deployed under org.mule.tools.maven in Central. Under the artifact id mule-maven-plugin, there are multiple files:
mule-maven-plugin-2.1.jar is the main artifact file,
which was created by the POM file mule-maven-plugin-2.1.pom,
while mule-maven-plugin-2.1-javadoc.jar and mule-maven-plugin-2.1-sources.jar are attached with their respective classifier.
As second example, consider the artifact id mule-esb-maven-tools. The only file deployed (except for the hash files) is mule-esb-maven-tools-1.1.pom. This is perfectly normal since it's a POM project, so it has no main artifact (there are no JARs or other deployed); there's only the POM file of the project, with no attached artifacts.
I'm working in eclipse and I have a problem that I can't import my personal java libraries.
I created the libraries and 'installed' them into my local maven repo (using mvn install). This created a subdirectory related to the 'version' name that was in the POM file from when I ran the command. Which seemed fine.
So in this directory there where the usual jar files and other stuff.
When I released this file I manually changed the name of the version in the POM. going from 0.0.1-SNAPSHOT to 0.0.1-RELEASE
This seems to have worked as I would have expected.
However I can't seem to find import the new release jar.
Using the maven repositories browser in eclipse I can see that the new artifact is in the 'local' repository.
I try to add the dependency in the following methods:
Select the main project -> Maven -> add dependency.
This adds the dependency details into the pom but with a type value detail of <type>pom.lastUpdated</type>
Select the project pom.xml file -> Maven -> add dependency.
This time the artifact for the 0.0.1-RELEASE is greyed out I can select it, but I guess nothing is actually happening.
The original 0.0.1-SNAPSHOT it selectable, and if I use this I do not have a <type> detail in the pom.
I don't understand why there is a difference in the RELEASE and SNAPSHOT artifacts, as they have both been generated in the same way, and clearly they are both visible in the browser, the contents of the directory on disk are the same. The file names and contents are identical with the exception of the word RELEASE or SNAPSHOT.
I know that I can simply add in the RELEASE jar to my build path, but this seems to be a ridiculous thing to have to do if I intend to use maven (or do I need to do this).
I don't want to use an external repo for storing my artifacts, and I'm not too keen to go to the trouble of installing nexus (or similar) on my local machine (just because I've had trouble with it in the past).
What am I missing so as I can get my maven project to see my local repository and all its artifacts.
Thanks in advance.
David
ps I've already tried things such as mvn dependency:purge-local-repository which definitely pulled in / updated all the local jar dependencies.
So I've managed to work around my problem.
As such this solution is ridiculous, and breaks all the purpose of maven.
So I found (from running maven from the cli) that there was an error in the parent of the project I was attempting to use.
The parent was missing a direct link to the scm plugin (version error).
Once I solved this problem, I then returned to the sub project, and got a lot of errors from missing stuff from the parent.
Essentially it was not 'seeing' all the log4j dependencies.
The solution (well non-solution really).
Add all the log4j dependencies to the sub project.
Edit in SCM and surefire test plugins (as it also started to fail the test code due to missing junit).
So this is great.
I have to define all my dependencies on log4j and in my sub / child project's pom.xml file.
I also need to define them all in my parent's pom.
As it then still refused to run tests in my new project (that used the above as a dependency), and refused to find log4j also. I then decided to add all of these as dependencies for my current project.
Great.
I thought the whole point of maven was I could define my dependency on log4j in my my logging library that I use (which is the dependency), and then it would 'automagically' pull in all the required from this dependency.
Clearly not.
As stated at the start. This is NOT AN ANSWER it is a crazy work around.
My logging library that I use should be able to define its own requirement on a specific log4j version (such as moving from log4j to log4j2), and then when I include this as a maven dependency any change to the required dependency should be seen automatically.
But No : I have to import the dependency on log4j in my other projects also. So now if I had updated my logging library from log4j to log4j2 I would need to go to all my project that use this library and update their pom's to ensure that I have the correct version of log4j.
Seems the whole point of maven has just been lost!
Can someone please tell me where I am going wrong!
David.
I am trying to understand relationship between artifact, group, class definitions.
For example, I've seen the following artifact declaration:
<groupId>org.seleniumhq.selenium</groupId>
<artifactId>selenium-java</artifactId>
<version>2.53.0</version>
Is there a file associated with this artifact?
Is this enough information to pull down the file down when building your Maven Project?
Where is it getting the file from? Is it getting it from selenium, or does Maven house these artifacts, and it is getting from Maven?
Where exactly is it downloading the artifact from?
What's in the artifact file? Class definitions? Multiple classes can be defined in there, right?
Maven seems to be making a jar file. Is it compounding all the classes into that file?
Also, how is artifact file different from JAR file and can you make your own artifact file?
Is there a file associated with this artifact?
Yes, what you have posted is known as a coordinate. It references a jar named selenium-java that is in the group org.seleniumhq.selenium.
Groups, identified by the groupId component of the coordinate, are a way of namespacing artifacts within maven to prevent naming collisions.
This coordinate says that the project has a dependency on version 2.53.0 of a maven artifact named selenium-java in the group org.seleniumhq.selenium.
Is this enough information to pull down the file down when building your Maven Project?
Yes, the coordinate is how the artifact is located within the maven repository and is enough information to locate and download the artifact when building a maven project.
Where is it getting the file from? Is it getting it from selenium, or does Maven house these artifacts, and it is getting from Maven?
Where exactly is it downloading the artifact from?
Where the file is retrieved from is based on your maven configuration. By default maven will first check the local maven repository on your machine to see if the artifact has already been downloaded. If not, it will then check Maven Central.
You can also host your own maven repositories using tools such as Nexus or Artifactory that can mirror repositories on the internet such as Maven Central as well as store artifacts you create yourself that you do not with to share with others.
What's in the artifact file? Class definitions? Multiple classes can be defined in there, right?
An artifact can be any type of file. In the case of the selenium coordinate above the artifact is a jar file. There will also be a pom file associated with that coordinate that explains all of the dependencies of the selenium-java jar.
http://search.maven.org/#artifactdetails%7Corg.seleniumhq.selenium%7Cselenium-java%7C2.53.0%7Cjar
Maven seems to be making a jar file. Is it compounding all the classes into that file?
You can build normal jars or fat jars with maven. By default maven will build a normal jar. If you wish to package all of a jars dependencies within it (i.e. fat jar) you need to use a special maven plugin.
http://maven.apache.org/plugins/maven-shade-plugin/
Also, how is artifact file different from JAR file and can you make your own artifact file?
Artifact is a generic term used to describe anything you can store within a maven repository. Maven repositories can store many different types of files. In the case of this coordinate the artifact is a jar file.
Is dependency-reduced-pom.xml created by Maven shade plugin automatically used in projects that depends on the uberjar (instead of the ordinary pom.xml)?
Asking this after reading a number of dependency-reduced-pom.xml related questions and haven't found the answer yet:
Maven shade plugin adding dependency-reduced-pom.xml to base directory
What is the purpose of dependency-reduced-pom.xml generated by the shade plugin?
What is `dependency-reduced-pom.xml` file which created when calling maven package command?
The dependency-reduced-pom.xml is generated at build time into ${basedir} of the project. This file is a temporary file that is only used for packaging into the shaded jar. Quoting the documentation of the createDependencyReducedPom attribute:
Flag whether to generate a simplified POM for the shaded artifact. If set to true, dependencies that have been included into the uber JAR will be removed from the <dependencies> section of the generated POM. The reduced POM will be named dependency-reduced-pom.xml and is stored into the same directory as the shaded artifact. Unless you also specify dependencyReducedPomLocation, the plugin will create a temporary file named dependency-reduced-pom.xml in the project basedir.
To make it clear, after the maven-shade-plugin has run:
your initial POM will be left unchanged;
a temporary file that you can completely ignore named dependency-reduced-pom.xml will have been generated inside the root folder (this is considered an open issue with this plugin);
the shaded artifact will contain your initial POM unchanged inside the META-INF directory and not the reduced POM (this is not really important but better mention it - there was an issue about this that was closed automatically: MSHADE-36);
the POM that will be deployed is the reduced POM;
the shaded artifact will be by default the main artifact of the project.
I have a situation where in my EAR file I have 'N' number of JAR files[modules] present. In these JAR files, there are certain artifacts which are duplicate. By duplicate, I mean the artifact name is same but with different versions.
Ex:
adapter-base-59.0-20141219-311675-3.jar
adapter-base-60.0-20141223-678915-68.jar
I would like to get help on how to find the source pom file location for these JAR files.
Any help on this is highly appreciated.
Regards,
Deepan
that might be a bit painful but the dependency can be in a parent pom.xml, a transitive dependency or a profile. Profiles can be in a settings.xml as well.
What I would do is execute mvn dependency:tree on the pom.xml where the dependencies are copied and then search where it comes from. Then follow that path.
It is a little weird you have the same jar twice with a different version. Usually maven takes the first one (or closest one) it find. So adding the correct version to your pom.xml has a distance of 1, that would always win - any transitive dependency will have a greater distance.
It might be the dependency uses a different groupId and maven cannot detect its the same artifact.
You could also try to open the jar files - maven usually adds some information into the META-INF directory (if you're lucky and the jar was release with the maven-release-plugin).