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>.
Related
I have a java project called "A" it has some custom annotations implemented in spring aop way and it is packaged as jar using maven jar plug-in, which contains only classes specific to project of A without any dependencies.now i have installed it in local maven repository using install command (mvn install:instlal-file) and used it as dependency in another maven project called "B".
I can able to get those annotations in project "B" but i cannot get dependencies automatically from pom file in dependent jar(project "A").due to which building project "B" is failing.
Q1: should we put all dependencies which we are using for project "A" in project "B" pom as well?
Q2: or it could get automatically downloaded from dependent jar pom file?
Note: am not interested in fat jar? but its working fine if we mention all dependencies in project "B". is there any way to get all dependencies when we build project "B" automatically?
Please help me in this.
I guess your error was to use mvn install:install-file. If you do not add the POM as parameter, an (almost) empty POM is created for you.
The right way:
Go to project A and run mvn clean install.
Then use A in B, and enjoy full transitive dependency resolution.
So, to summarize, the answer for Q1 is "no", and the answer for Q2 is "yes, use mvn clean install instead of mvn install:install-file.
I want to know why OSGi do not respect the maven dependenceis.
I want to create one app in OSGi(AEM). I want to communicate(CRUD) to the database with the help of JPA(eclipselink).
I created maven project with aem-archetype.
Added all required dependencies(of JPA) into my maven project's pom file.
No errors in Eclipse, I built the project via mvn clean install and installed it into AEM(CQ5) via mvn sling:install. All good till now. No Errors.
But when I go and see my bundle in the felix console, I see that it is not Active but in Installed state.The error reported is that it could not resolve the javax.persistence package.
I was puzzled, I searched and I read about it here -
You have to make sure that you place the same version in another
bundle and deploy first. https://forums.adobe.com/thread/2325007
I converted JPA jar to OSGi bundle and installed in my OSGi container, and the error was gone. Great!
But why OSGi is not watching out for the dependencies I wrote in pom.xml of my maven project. Why it needs JPA strictly from OSGi bundle?
Maybe this is due to any architectural benefit, but could anyone please explain me here about this behaviour of OSGi? And why/how this feature of OSGi is useful ?
The <dependency> section of your Maven POM only covers your compile time dependencies. That means when you run Maven to build your project those dependencies are used to compile the source code and build your bundle. Maven itself is not aware of AEM or OSGi or any other platform or framework (e.g. Spring).
Maven just compiles your code.
You, as a developer, are responsible that all those required compile time dependencies are also available at runtime.
What we usually do is to create an AEM content package Maven module and put all of our required third party dependencies (e.g. JPA bundles) into it. This content package is then deployed by Maven so that those dependencies are also available at runtime.
Reason is: what you are adding as dependency is getting added in build path of your project and being available for your classes.When you run mvn install,it checks presence of all dependency and creates a bundle/jar for you.By default this bundle has only your project classes not other dependencies.
You need to check in depfinder whether external dependencies are already there in OSGi container,if not you have to load them in OSGi container either by embedding external dependencies in your bundle with the help of maven-bundle-plugin present in pom.xml or by making a bundle of jar file(I wont recommend that)which you have done.
I hope this helps!
I have maven projet with this architecture:
++parent-project
+module-a
+module-b
module-b is a web application. it will be run on Jboss AS 7.1.1. I'm using netbeans IDE.
Now module-b depend on module-a. this is a porm section of module-b:
<dependency>
<groupId>groupid</groupId>
<artifactId>module-a</artifactId>
<scope>compile</scope>
</dependency>
When i build the war file of module-b, module-a is not present to lib folder ( in war file. i open it with archive explorer ). therefore JBoss return ClassNotFoundException.
I'm tried differends scope ( compile , provided , runtime , test ). But nothing.
Please how can i solve this.
First of all, I think you should try to see how does it work in "pure" maven, without the IDE at all (NetBeans). So my answer will be based only on maven knowledge:
A couple of facts:
Module b has to have the following in pom: <packaging>war</packaging> This will instruct maven that you really want to get a war from this module.
When packaging WAR is specified in some pom, maven will take all the dependencies defined in this pom and will put them into the WEB-INF/lib folder of the war. Automatically. Of course, you can customize the output, but its more advanced stuff (see Maven WAR plugin if required)
All the dependencies have to be defined with group id, artifact id, and version at least. So make sure that you have the dependency on module a with version. There is no need to fiddle with scopes in this case. The default scope (if you don't specify a scope at all) is 'compile' which is fine.
Go to the directory of module b and from within the directory type: mvn dependency:tree. Once its done, please carefully observe the output, especially make sure that module a is listed (with a correct version) in a tree.
Sometime to make sure that no stale artifacts reside in the local m2 repository you might want to delete all the jars of your project from there and then execute the mvn package command again. The war has to be created in module b/target - and this is the WAR you should check out.
Note, all these steps are done without any interaction with NetBeans at all.
I am a maven newbie. My project depends on another maven project (ProjectA) in that I need to run mvn clean package on ProjectA which gives me JarA.
Then, I need to run java JarA feeding it with an xml configuration file which gives me another JarB. I need both JarA and JarB as dependencies on my project (ProjectB).
Any comments on whether it is possible to achieve these steps in projectB's pom file? Would having parent-submodule type of a configuration help? Thanks!
Maybe. The most simple solution to get JarB would be to add a unit test to project A. But that doesn't tell Maven about this JAR, so it will ignore it.
The next step would be to get the test to write JarB as JarA-config into the target/ folder of project A. Maven supports multiple artifacts as "build results". You can then use the "qualifier" to distinguish between them.
Use build-helper:attach-artifact to tell Maven about the second JAR. See "Attach additional artifacts to your project" for an example.
Note that package happens after test, so your test case can create the second JAR and build-helper will then find it.
In project B, you can then use this to depend on both JARs
<dependency>
<groupId>x</groupId>
<artifactId>jarA</artifactId>
</dependency>
<dependency>
<groupId>x</groupId>
<artifactId>jarA</artifactId>
<classifier>config</classifier>
</dependency>
Note the additional <classifier> element.
Note: For this to work, you need to run mvn install in project A.
Sonatype's Maven:The Complete Reference says that a compile scoped dependency is on all classpaths and is packaged with the artifact.
Compile is the default scope; all dependencies are compile-scoped if a
scope is not supplied. compile dependencies are available in all
classpaths, and they are packaged.
I can't see that they are packaged though . . . doesn't this mean that they should be contained in the jar file? If not, what does it mean?
You are correct. Compiled scope dependencies does not get packaged with the output jar. (with JAR plugin). I think the 'package' refers to the end product (binary executable).
I came across this stackOverflow thread (How can I create an executable jar with dependencies using Maven?). Here they are packaging all the dependencies to build a executable out of Main class. In that case you need all the compile time dependencies in your packaged executable. (since JAVA lazy loads it is not a must, but preferable to have all the compile time dependencies)