My project has a dependency (Provided Scope), then If I run my project under Test Scope for unit tests, then how does Maven find this dependency it needs during unit testing?
Would Maven just use the one in local maven repository (if exists)?
Thank you.
From official documentation:
A dependency with this scope is added to the classpath used for compilation and test, but not the runtime classpath.
So yes, during test phase the dependency will need to be available (or will be downloaded) in your local Maven repo.
Related
My project has a dependency for which the scope must be set to provided. But when I run the project from my local environment, the scope must be compile. Is there anyway I can define the scope as provided in my pom, but override it when I run from my local environment?
I think the best approach would be using maven profiles, in this way you can leave dependency with proper scope in main dependencies tag and re-declare it whithin your "local" profile.
Then you just have to invoke
mvn clean package -Plocal
to run the build triggering local profile and therefore getting the dependency with the modified scope.
In this way standard build is unaffected and you can run all your build locally with all needed changes as well
I have Maven dependencies with scope test.
I add flag Dmaven.test.skip=true but Maven still brings test dependencies.
Is there a way not to bring test dependencies if I want to build only the production part?
This is how maven works - it First tries to check that ako dependencies are available, no matter their scope. Only then it continues to test phase to find out that tests should not be executed.
A possible workaround is to define your test dependencies in a separate test maven profile, which is not applied when you do not want to run tests. Profiles are resolved before any dependence are downloaded, therefore if test dependencies are not added by the profile to the effective pom, they are not downloaded at all.
the flag -Dmaven.test.skip will only skip compilation and execution of your tests within the project you run.
Its often better to use -DskipTests as this will compile the test classes but not run them. See surefire documentation.
This has nothing to do with dependencies. Those are loaded into the classpath depending on their scope and what plugins require. The surefire plugin requires resolution of scope test as it runs the unit tests.
If there are dependencies of scope test which you do not want to use you need to remove them or exclude them if they come in via transitive dependencies (dependencies of dependencies). You can execute a mvn dependency:tree to figure out why jar are in the project.
If you add some dependencies for test scope, maven will first check if the dependency is available or not then it checks the scope.
You can create a maven profile, add test dependencies under the profile and trigger the profile when -Dmaven.test.skip or -Dmaven.test.skip=true option is not present. In this way you can keep your build command unchanged.
You can check this simple project manage-test-dependencies-in-maven-the-proper-way to understand it better.
According to the Maven lifecycle, mvn install will "install the package into the local repository, for use as a dependency in other projects locally". The local repository then stores all the jars that I downloaded remotely.
My modules have dependencies with other modules. When I run mvn package, nothing is stored in my local repository, but the dependencies appear to be fulfilled. So how does Maven handle the inter-module dependencies? Does Maven refer to the jars of each module from the built target directories or does it fetch them from another location?
Corey,
You are correct, going strictly by Maven docs implies mvn compile on:
parent_pom/
subA/
pom.xml
subB/
pom.xml # depends on subA
should fail since subA hasn't been pushed out to the local repo.
What's happening under the hood is that Maven uses the reactor to trick the build into looking into target dir of earlier submodules on the same build.
Beyond the scope of this particular question, the maven-reactor-plugin is one of the most opaque parts of Maven, but also one of the most powerful if you master it. You would do well to read up on it.
Hope that helps.
It depends on the phase you're executing. Before compile, Maven will fail, since there are no classes compiled. Between compile and package, the target/classes is used. For package and later, the target/artifactId-version.jar is used.
Trying to avoid the use of jargon, so that I don't get misinterpreted.
Here is the scenario, My project requires a jar in order to get compiled(let say x.jar). My project get once compiled gets converted into a WAR file, which gets deployed somewhere.
Now I want x.jar just to be there for my project to compile and it should not be packed(or part of) inside WAR file.
How can I do this in Maven ? should I used dependency scope as "provided"
You are right, as stated in the Maven FAQs, the scope to use is provided,
How do I prevent including JARs in WEB-INF/lib? I need a "compile only" scope!
The scope you should use for this is provided. This indicates to Maven that the dependency will be provided at run time by its container or the JDK, for example.
Dependencies with this scope will not be passed on transitively, nor will they be bundled in an package such as a WAR, or included in the runtime classpath.
To quickly try it out, you can use
mvn archetype:generate -DarchetypeGroupId=org.apache.maven.archetypes -DarchetypeArtifactId=maven-archetype-webapp
to generate a "toy webapp" project, add a dependency to your project and set it to <scope>provided</scope>.
I'm looking for a way to modify the class path in maven. Why?
I want to instrument maven artifacts without corrupting the local repository such that when surefire-tests run it will see the instrumented classpath, not the original class path.
In general maven manages the classpath by itself.
Having said that, there are a couple of options you can try here:
You can use 'additionalClassPath' parameter in surefire plugin. You can read about ithere:
You can generate your instrumented jars and use them in scope test, don't use un-instrumented jars in the tests at all
Hope this helps