Maven packaging web application - maven-2

i removed one un-used dependency from pom.xml of the project which had packaging of war kind.Even after removing it, it is getting bundled under lib folder.
Why is this so?
Appreciate your inputs

execute following command to see your actual pom
mvn help:effective-pom
or outout it to a file
mvn help:effective-pom > effective-pom.xml
now go through the generated effective-pom.xml

Related

How to deploy pom.xml as SNAPSHOT with maven?

I have a pom.xml and i want to use it as the parent pom.xml of my project.
and want to make the name for the pom.xml which was uploaded on Nexus like ABC-root-pom-2.0.0-SNAPSHOT.pom
so could anyone tell me what the command is using maven ?
Thanks
Do not worry about what name the pom will have on the repository manager. The Maven repository format dictates that.
To get a Maven project with pom packaging deployed you have to do the normal steps of adding the distributionManagment to the pom and the credentials to the settings.xml. Then you run
mvn clean deploy
and thats it. Your other project can then reference it. An example for such a pom project is my progressive-organization-pom.

How to compile pom.xml without generating project in Maven?

I have pom.xml file that contains dependencies and files to checkout from svn so there is no no need to generate project. I just need these libraries and those files, so is there any way to get them without generating a project with maven directory structure?
I'm not sure from your question what do you want. If you have pom.xml file and you want to download all dependencies defined in it, you can call
mvn dependency:copy-dependencies
For more options look maven copy-dependencies task page
If you are asking how to create pom that will contain no code, but only dependencies, you can do that by specifying pom packaging.

How can I view transitive dependencies of a Maven pom.xml file?

Is there a CLI tool I can use to quickly view the transitive dependencies of a Maven pom.xml file?
On the CLI, use mvn dependency:tree
(Here are some additional Usage notes)
When running dependency:tree on multi-module maven project, use mvn compile dependency:tree instead1.
Otherwise, the POM Editor in M2Eclipse (Maven integration for Eclipse) is very good, and it includes a hierarchical dependency view.
1If you don't compile, you might get error Failed to execute goal on project baseproject: Could not resolve dependencies for project com.company:childproject:jar:1.0.0: Could not find artifact. This might happen because dependency:tree command doesn't build projects and doesn't resolve dependencies, and your projects are not installed in maven repository.

Using Maven ant task to install jar to local repository

At the end of my ant build id like it to call the equivalent of the command line call
mvn install:install-file -Dfile=my.jar -DgroupId=com.company.project -DartifactId=my_project -Dversion=1.0 -Dpackaging=jar -DgeneratePom=true
so that it will add the newly built jar to a maven repository which another project will rely on.
Ive tried using the maven-ant-task and have added the maven-ant-task jar to the ant built project and the following code to the build.xml:
<target name ="minstall" depends="jar">
<artifact:pom id="maven_install" file="maven_install.xml" />
<artifact:install file="${out.dir}/my_project.jar">
<pom refid="maven_install"/>
</artifact:install>
</target>
but seem to be missing something as it wont work for me. To begin with i get the error in the build.xml (ant build file) saying
The prefix "artifact" for element "artifact:pom" is not bound.
What am I doing wrong. I am fairly new to ant?
On a realted question what is the purpose of the associated POM file? I would not normally have a POM in this project as it is an ant build
Perhaps maven-ant-task jar is not installed, i.e. not in your ant CLASSPATH. You can follow this instruction for this.
As mentioned previously, you need to make sure the tasks are defined in your ant script, and the artifact namespace is understood.
The POM file is used (in this case) to tell the Maven repositories the dependencies of the JAR you are putting in the repository. The POM should also specify the JAR's identification information (groupId, artifactId, version number, license, etc.).
Strictly speaking, you do not need an external POM, you could define the information in your build.xml file as follows:
<!-- Assuming tasks defined, and 'artifact' namespace exists -->
<artifact:pom id="maven_install" groupId="com.whatever" artifactId="some-jar"
version="1.0" packaging="jar">
<dependency groupId="..." artifactId="..." version="..."/>
<dependency groupId="..." artifactId="..." version="..."/>
<license name="apache" url="http://www.apache.org"/> <!-- can be omitted -->
</artifact:pom>
<target name ="minstall" depends="jar">
<artifact:install file="${out.dir}/my_project.jar" pomRefId="maven_install"/>
</target>
When you install the JAR in the 'minstall' task, the POM should be generated with the appropriate dependencies in the local Repository.
That message means you are missing an xmlns:artifact attribute in your build.xml. Have a look at the installation page in the docs for an example.
As to the purpose of the POM file, it's mostly metadata so that maven can figure out dependencies properly. In a real maven build it also describes how to build, test and package. But in your case all that is done by ant instead.
I think that it makes no sense to put such commands in Ant's build.xml. If you want to have your jar file installed in your maven repo just use mvn install command.
Besides that, I guess that you are somehow confusing the purpose of Maven and Ant tools in your project. What I'd suggest is to use Maven as your main build tool. You can configure invokation of Ant targets in your POM file if you really need that. Personally, I think it is the best solution to have Ant called by Maven. Maven goals (such as clean, test, package, install and so on) are very simple to use and powerful (I guess that you can read it in every Maven tutorial).

Multi-module project in maven

I have some multi-module project.
Some modules are packaged as wars and some as jars.
When I start from the root module : mvn war:exploded I thought it would apply the step only to the war projects. But it tries to apply the mvn war:exploded on all the projects which obviously fails (no web.xml and so on).
Any ideas how can I tell maven to apply in only to the war packaging modules?
When running war:war (which is the goal bound to package for a project with a war packaging), the war plugin automatically creates a directory of the exploded war file first and then compresses it into the actual war file. So why don't you simply run mvn package during your reactor build?
If really this is not an option, you could maybe use one of maven's advanced reactor options, and more precisely:
-pl, --projects
Build specified reactor projects instead of all projects
and list only the war modules.