Develop Reference

How to handle multiple test environments in maven?

I'm building a project using maven and I need to ensure it works over Java SE and different Java EE containers. There're already integration tests written for WildFly container. And now I'm moving to Java SE.
But face to this multiple test environments, how should I handle them in maven ? Should I use <profile>, <module> or something else ?
<profile> is useful to switch between different profiles and each of them can have their specific dependencies. So in my case, there might be profiles: wildfly-embedded, wildfly-managed, java-se etc. But I need to ensure the project works on every profile, is it possible to run all the profiles in one command ?
<module> can handle project inheritance. After reading the post SO • Why and when to create a multi-module Maven project?, I'm still confused about if I should use it in my case.
Can somebody give me some ideas ? That will be very helpful, thanks.

If you keep in mind that the resulting artifact should always be the same no matter the activated profiles, then you should understand that profile is not the correct solution (although it is very often abused for it. Don't try to go for that advice!)
Configuration should be outside the artifact, so you can reuse the same artifact over and over again. Since many people ask for the proper solution with embedded configuration, Karl Heinz created https://github.com/khmarbaise/multienv-maven-plugin . This is probably the closest you'll get to a valid Maven project setup.

How to separate class loader for different jar version?

I have a test war file that contains many tests. Each test is packaged in maven project with a lot of dependencies. We use maven for dependency management but it comes with a problem. When a test update a common library, it can break other test that depends on the older version of the lib. How to make all the test run in a completely separate environment with its own set of library version? I can't execute them in a separate jvm because these tests need to be executed very frequently like very 30 sec or so. Can OSGi help solve this problem?

Yes OSGi can solve this problem, but it is not a step to be taken lightly. Use OSGi when you are ready to commit time and effort to isolating and managing dependencies, versioning them properly and, optionally, making your code and architecture more modular/reusable.
Bear in mind that adopting OSGi can be painful at first due to non-modular practices used by some legacy libraries.

How to find out which dependencies need to be included?

I'm fairly new to Java/Spring and am trying to put together a simple app which will include some basic CRUD operations and I'd like to use Hibernate for data access.
I'm using Maven as my build tool. My question is: how can I find out which dependencies are required to use Hibernate? For example, I'm using Spring 3.0.6, but how would I know what version of Hibernate to use with that version of Spring? More over, if there are multiple possible Hibernate dependencies, how would I know which ones to include for the functionality I need? So far this seems to be partially reading documentation and partially trial and error.
Is there a definitive way of knowing which Maven dependencies to use with certain version of other dependencies? Any which dependencies to use for particular bits of functionality?
Thanks,
James.

I follow these steps when starting to use a new framework:
Go to framework's web site. In your case hibernate web site and try to find latest (or a specific) version. For hibernate it is 3.6.8-Final at the time of writing.
Search for a maven dependency definition on the framework web site. If you can not find any dependency definition, them simply google for "frameworkname _version_ maven dependency" and you'll most probably find necessary definition, as well as the necessary repository information. For example you can find the dependency definition for hibernate on mvnrepository.com and necessary artifact repository information on Hibernate 3.6.8 release page:
The artifacts have all been published to the JBoss Nexus repository under the org.hibernate groupId at http://repository.jboss.org/nexus/content/groups/public-jboss/
The question of which dependencies are necessary and which are optional depends entirely on the framework to be used. So for example in order to use hibernate, as stated on Hibernate Quick Start Guide:
hibernate-core: The main artifact, which contains all the Hibernate classes, in packageorg.hibernate. You need these to build applications using the native Hibernate APIs. It includes capabilities for using native Hibernate mapping in hbm.xml files, as well as annotations.
About compatibility issues (which version of hibernate is compatible with spring 3.0.6), all I can say is you have to read about integration manuals for those frameworks. Since Spring and Hibernate are two exclusively distinct frameworks, I don't think you can find a constant location to look for version compatibility matrix or something like that.

The purpose of Maven is to avoid handling dependencies by hand. Just choose which version of Hibernate to use and include it in your pom; Spring supports many different versions.
If you know what parts of Spring you want to use, just include those parts in your pom; they'll include their own requirements.
Is there a specific module and/or version combination you're having an issue with?

The only way to know for sure that you've got all dependencies is by running your app.
Maven resolves for you transitive dependencies so you can quickly detect missing ones by compiling the java code.
However, in a web app there are many dependencies that are required in runtime only, so they are not detected at compilation time.
you can find out the dependencies by running mvn dependency:tree and analyze if they are required or not by running mvn dependency:analyze.

Taking the newest ones usally works as long as they are stable.
Start with hibernate and spring core, context, tx.
After you added some could you will probably recognize that something else is missing.
Try and error doesn't sound good, but its working pretty well for spring dependencies.

Create web application framework with Maven

we are trying to develop a web application framework and build implementatins on top of it. This framwork will be versioned in SVN, live its own life in parallel to those implementations. It will have lots of spring config files, security config and so on. We would like to use those in those implementations.
What structure should such an project have? Keep everything together? Link particular folers (implementations) in "svn: externals"? We would like to use Maven, and create an archetype for those implementations, but is it possible to update the archetype after it has been changed in implementation applications?
Regards,

This is a good example :
http://www.sonatype.com/books/mvnex-book/reference/web.html
Also this book is very useful resource when starting with maven
I found this also :
http://www.avajava.com/tutorials/lessons/how-do-i-create-a-web-application-project-using-maven.html

I'd suggest you create your framework project as a simple jar project to include in your implementation, which would be war projects. For the Spring config files you have three options then:
Package them into your framework jar. This would make it hard for the implementations to customize it. I would not recommend it, unless your configuration is definitively fixed.
Use svn: externals. I have not much experience with that, but I think dependencies between svn repositories would be hard to manage.
Maintain these configuration files per implementation. So, an archetype would help to get started with an initial configuration. Then maintain these configuration files as your framework evolves. This is what we do most of the time. The good thing about Spring configuration is that it often rarely needs to be touched once you are confident with it.

Quick and easy way to test OSGi bundles

Currently, I am working on a new version control system as part of a final year project at University. The idea is to make it highly adaptable and pluggable.
We're using the OSGi framework (Equinox implementation) to manage our plug ins. My problem is that I can't find a simple & easy to use method for testing OSGi bundles.
Currently, I have to build the bundle using Maven and then execute a test harness. I'm looking for something like the JUnit test runner for Eclipse, as it will save me a bunch of time.
Is there a quick and easy way to test OSGi bundles?
EDIT: I don't need something to test Eclipse plug ins or GUI components, just OSGi bundles.
EDIT2: Is there some framework that supports JUnit4?

More recently, you should have a look at Pax Exam:
http://team.ops4j.org/wiki/display/paxexam/Pax+Exam
This is the current effort at OPS4J related to testing.

Here are some tools not mentioned yet:
I'm using Tycho, which is a tool for using Maven to build Eclipse plugins. If you create tests inside their own plug-ins, or plug-in fragments, Tycho can run each set of tests inside its own OSGi instance, with all its required dependencies. Intro and further info. This is working quite well for me.
jUnit4OSGI looks straightforward. You make subclasses of OSGiTestCase, and you get methods like getServiceReference(), etc.
Pluginbuilder, a headless build system for OSGi bundles / Eclipse plug-ins, has a test-running framework called Autotestsuite. It runs the tests in the context of the OSGi environment, after the build step. But, it doesn't seem to have been maintained for several years. I think that many Eclipse projects are migrating from Pluginbuilder to Tycho.
Another option is to start an instance of an OSGi container within your unit test, which you run directly, as explained here.
Here's someone who's written a small bundle test collector, which searches for JUnit (3) tests and runs them.

Spring Dynamic Modules has excellent support for testing OSGi bundles.

There is a dedicated open source OSGi testing framework on OPS4J (ops4j.org) called Pax Drone.
You might want to have a look at Pax Drone ([http://wiki.ops4j.org/confluence/x/KABo]) which enables you to use all Felix Versions as well as Equinox and Knopflerfish in your tests.
Cheers,
Toni

Eclipse has a launch configuration type for running JUnit tests in the context of an Eclipse (i.e. OSGi) application:
http://help.eclipse.org/stable/index.jsp?topic=/org.eclipse.pde.doc.user/guide/tools/launchers/junit_launcher.htm

If you need to test GUI components I've found SWTBot gets the job done.

Treaty is a contract(testing) framework that is pretty academic but has some nice ideas. There are papers that are published on it, and the people currently working on improving it.

The ProSyst Test Execution Environment is a useful test tool for OSGi bundles. It also supports JUnit tests as one of the possible test models.

For unit tests use the EasyMock framework or create your own implementations of the required interfaces for testing .

I think we met the same issue and we made our own solution. There are different parts of the solution:
A junit4runner that catches all OSGi services that has a special property defined. It runs these caught services with JUnit4 engine. JUnit annotations should be placed into interfaces that the services implement.
A maven plugin that starts an OSGi framework (a custom framework can be created as maven dependency) and runs the unit tests inside the integration-test maven lifecycle.
A deployer OSGi bundle. If this is dropped into your OSGi container a simple always-on-top window will be opened where you can drop your project folders (from total commander or from eclipse). This will then redeploy that bundle.
With the tools you can do TDD and have the written tests always run inside the maven integration-phase as well. It is recommended to use eclipse with m2e and maven-bundle-plugin as in this case the target/classes/META-INF/MANIFEST.MF is regenerated as soon as you save a class in your source so you can drag the project and drop to the deployer window. The OSGi bundles you develop do not have to have any special feature (like being an eclipse plugin or something).
The whole solution is OpenSource. You can find a tutorial at http://cookbook.everit.org

During the last couple of years Tycho - a new Maven based build system for OSGi - has become rather popular among the Eclipse Foundation. This framework also includes method to use Maven Surefire to test OSGi bundles in separate testbeds...

There are many ways to test OSGi components, I suppose. One way of doing the testing is to use Robot Framework. What I've done is made my tests with Robot Framework and have the remote libraries either installed in OSGi or have them talk to OSGi-test components through sockets and robot would talk to these modules and run tests through them.
So, basically your OSGi-modules should have interfaces that do something and produce some output. So, in my setup I had a test components that would make service calls to the actual OSGi-component and then there would be a listening-service that would catch the events/service calls (made by the module under test) and those results could be asked by the robot. So basically this way you can split a massive system in small components and have the system run in production/production like enviroment and have it tested automatically on component level or have some of the real components be tested in unison.

Along with others mentioned mockito is very handy to mock plugin dependencies(references etc). see https://www.baeldung.com/mockito-annotations

How about bnd-testing-maven-plugin?
It allow running JUnit inside a running container like Felix or Equinox.
If you used the BNDTools for eclipse this is very similar but just maven withpout eclipse and without a UI.
https://github.com/bndtools/bnd/tree/master/maven/bnd-testing-maven-plugin
also look at the effectiveosgi archetype for maven. This will give you a good starting point to build your project or just add tests.
https://github.com/effectiveosgi