In eclipse, maven dependencies are overriding project dependencies - java

I have a "master project" that uses several "modules". The modules are in the pom.xml, but I also have the code for the modules as projects in Eclipse. I defined the modules as project dependencies both in "Properties|Project References" and in "Properties|Java Build Path". I also made sure all of the Eclipse projects are at the top of "Order and Export" in Java Build Path.
The master project is not recognizing changes to the modules within eclipse. When I press F3 to see the code, it opens java source from my .m2 directory. It's obviously ignoring my Eclipse projects. Am I missing some setting? What should I do?

You don't need to add the dependent projects into the Project references (at least when using m2eclipse-plugin), just add them as dependencies on your masters' pom.xml. I haven't had the need to touch the Build path since I've started using Maven in Eclipse.
Make sure you have enabled the Workspace resolution of the plugin by right clicking on project root -> Maven -> Enable Workspace Resolution. If it says "Disable Workspace Resolution", it is already enabled. You may also need to run "Update project configuration" under the same menu.
This way when you run your master-project from within Eclipse, any changes made to the other projects will be "visible" to the master (and you can actually use hot swap during runtime even on the other projects).

If you're using Maven, you pretty much want to commit to Maven. Even if you do configure Eclipse with Eclipse-specific dependencies, anytime you update your project configuration using Maven, it will do a complete rewrite of your configuration.
I strongly recommend converting any of your other project build dependencies into Maven-enabled projects that can be used as Maven dependencies.
In your specific case (through using the Maven modules), this means ensuring that each of your modules are imported into Eclipse as m2e-enabled projects. m2e will then automatically wire in the dependencies between modules and other dependent projects.

Im scratching my head as to why you would need your modules defined as dependencies on your top level project. Are you trying to avoid having to define the (cross) dependencies at a module level? In any case, as per other suggestions, first of all put your dependencies in the correct places in your POM, then either run
mvn eclipse:clean eclipse:eclipse
to update your Eclipse settings, or better still, make sure m2eclipse is installed and import your maven projects directly into the IDE.

Related

Eclipse: reference local code instead of cached gradle dependency

I have two gradle java projects imported into Eclipse, one being a dependency of the other.
I would like for Eclipse to use the local dependency code, instead of the compiled dependency in the gradle cache folders, so I can modify and debug both projects simultaneously.
How do I force Eclipse to use a local dependency code?
The feature you are referring to is known as Composite Builds:
Importing into the IDE
One of the most useful features of composite builds is IDE integration. By applying the idea or eclipse plugin to your build, it is possible to generate a single IDEA or Eclipse project that permits all builds in the composite to be developed together.
In addition to these Gradle plugins, recent versions of IntelliJ IDEA and Eclipse Buildship support direct import of a composite build.
Importing a composite build permits sources from separate Gradle builds to be easily developed together. For every included build, each sub-project is included as an IDEA Module or Eclipse Project. Source dependencies are configured, providing cross-build navigation and refactoring.
The most simple way of achieving this is to use includeBuild in your settings.gradle.
rootProject.name = 'my-composite'
includeBuild 'my-app'
includeBuild 'my-utils'
With that in place, there's no need to configure the build path manually in Eclipse.
Gosh this was a trivial one and it took me way too long to figure it out.
Solved the issue by creating a file named external-projects.properties in the root folder of the parent project with the relative or full path to the dependency project folder.
To be precise, for me the folders tree ends up like this:
git-folder/
|__parent-project/
|__external-projects.properties
|__build.gradle.kts
|__rest (src/main, etc)
|__dependency-project/
|__build.gradle.kts
|__rest (src/main, etc)
And the contents of the external-projects.properties file:
dependency-project = ../dependency-project
The dependency project must also be in the build path of the parent project (done by "Right-Click project > Build Path > Configure Build Path" and adding it in the "Projects" tab).
After that, a "Right Click > Gradle > Refresh Gradle Project" did the trick.

Eclipse fix project setup by updating pom?

In an eclipse project, I referenced a class that was currently not in project's build path.
In the context sensitive pop-up that opens by hovering the mouse over the error, "Fix project setup" option has offered me to add a jar to the build path of the project. This jar is in my local maven repository.
However, the "correct" way to fix it is obviously by adding the relevant dependencies to my project's pom, instead of adding this jar to the build path of the project.
So is there a way to configure eclipse, so that it won't offer to add a maven repo jar to the build path, but it will offer to fix the project's pom?
This feature used to exist in m2eclipse (the predecessor of m2e), see e.g.
https://blog.sonatype.com/2010/03/adding-dependencies-using-m2eclipse/ which shows a "Search dependency for XXX" quickfix above the "Fix project setup..." quickfix.
Unfortunately it didn't make it into m2e, see https://www.eclipse.org/lists/m2e-users/msg01130.html
Make sure:
your project is fine outside of eclipse using only maven/pom, mvn
clean install (or similar) in an external shell/console
your eclipse project has maven nature
Eclipse -> Project -> Build Automatically is checked
Refresh your eclipse project
Do something in the pom.xml (save file) should trigger a build

How to remove Modules from a Intellij Maven Project permanently?

I am currently working on a larger scale Maven-based project in IntelliJIdea 12.1.6 Ultimate. I have been working with IntelliJIdea since about 5 months.
An included module has dependencies on another module. The dependent module's source was also part of my project until recently. Since I removed the dependent module from my project, I get compile errors whenever I am trying to compile the source without maven.
The pom.xml of removed modules in Intellij seem to be placed onto the Settings->Maven->Ignored Files. I cant seem to remove it from there, only check or uncheck it. It's not possible to include the module again since IntelliJ will say its still under Ignored Files.
2 ways allow me to compile again: Uncheck the pom from Ignored files, which will include the module again in my project. Or delete the source of the dependent module, so my project will load the dependent module from the maven repository. But whenever I update my project from svn, the source of the dependent module is restored (I don't know why this even happens since its not part my project) and the cycle begins anew.
I googled this for a while since it gets really annoying. It became a problem with several excluded modules. I could rebuild the intellij-project from scratch but since a lot of IntelliJ settings were made (not related to the problem) I would rather solve this.
Any help is appreciated, I guess I must be missing something
A collegue who has more in-depth knowledge of maven told me the answer:
The trick is not to remove the source module from the intellij project but to remove it from maven (in the maven projects tab in intellij). Intellij will ask then to remove the source module also from the intellij project and its finally gone.
Right click on the maven project -> remove projects
Would not have guessed this makes such a difference.
Do any of these two points work for you:
NEW there might be dependency in one of your sub-modules pointing to the removed artifact. To make sure it's the situation, you may want to rename your $HOME/.m2 and rebuild the project. If this is indeed the case, just search for the dependency in your poms and delete it from sub-modules
right click on the parent pom.xml -> Maven -> Reimport
copy the project into a separate dir. File -> Import Project -> Choose newly created dir -> Choose Maven?
PS. Idea is excellent in maintaining the project structure in accordance with Maven project. Once you make a change to your pom, you need to reload the project. Idea can also automatically detect changes made to your pom.xml and apply them to project. To enable this, press Ctrl+Shift+A, type 'maven auto', choose "Importing", checkbox "Import Maven project automatically";
This may not relate directly to the OP, but...
Using IntelliJ 2016.5, to remove a Maven module and it's underlying source code and remove it as a sub-module from the parent, go to the Project Files tab, find the unwanted module and use the triangle symbol to open it, then delete the entry that represents it on disk.
Hitting Delete on the module itself will only mark it as hidden within the IDE.

Adding POM Dependency in Eclipse build path

I have a project with a number of POM files. I have done a clean install and eclipse:eclipse. I would like to import the project as a normal project rather than Maven project. When I imported the project as normal project , I was not able to see the Maven dependencies present in POM in eclipse's build path. Is importing the project as Maven project only way of doing it? When I import the project as Maven project I see a number projects in eclipse workspace (one for each POM). However I would like to view this as a single project in eclipse workspace.
UPDATE: The classpath files of the child projects contain the dependent jar files , however it is not added to build path when the main project is added. Only the entries in classpath file of the main project is being added.
Given that you refer to "Maven project", are you using an eclipse plugin for Maven like M2Eclipse?
Assuming you are using M2Eclipse, the Maven Dependencies Library is automatically enabled for a Maven project. For a normal Java project, importing the library would force you to configure the project as a Maven project (On the context menu for the project, select Configure -> Convert to Maven Project).
Having said that, while you import your Maven project, you will notice an "Advanced" option (towards the lower section of the "Import Maven Projects" dialog). When you expand this option, there will be a checkbox to "Resolve Workspace Projects" - this is checked by default and is hence responsible for importing the child modules as separate projects. If you uncheck this, it will import only the parent module as the project and all children modules will be in sb folders under the parent module.
IMO, resolving the projects provides greater clarity, but then again this is very much a personal choice.
Hope that helps.
Eclipse doesn't support nested projects, and Maven kinda forces you to. So you can't really push everything into one project.
Doing a cursory google search led me to this, which might be helpful: http://warpedjavaguy.wordpress.com/2011/08/08/how-i-defeated-the-maven-release-plugin-in-a-flat-structured-multi-module-project/
You might also check out the following two online books from Sonatype:
Maven: The Complete Reference and Developing with Eclipse and Maven
Personally, I create Working Sets for each multi-module project and add all the individual projects to it. This enables me to see them all grouped together, this might be to your liking.
http://help.eclipse.org/indigo/index.jsp?topic=%2Forg.eclipse.platform.doc.user%2Fconcepts%2Fcworkset.htm
Once you have created the working set you can enable/disable them in the menu in Project Explorer and configure the project explorer to display the working set as the root element in the tree rather than the project.

Getting m2eclipse to match maven's classpath

I've got project with a few sub modules.
mvn clean install
works absolutely fine. But in Eclipse with the parent project open none of the maven dependencies are available and so all my Java source files are full of indicated compilation errors (they're not listed in the build path for the project). If I open one of the sub modules as a project there are no indicated compilation problems.
I've tried running
mvn clean install eclipse:clean eclipse:m2eclipsemvn clean install eclipse:clean eclipse:m2eclipse
and choosing project / update maven dependencies. Refreshing, closing and opening the project and Eclipse, etc.
Any ideas? Thanks in advance.
Getting m2eclipse to match maven's classpath
Just use Import... > Existing Maven Projects and import your multi-modules Maven project, that's all.
But in Eclipse with the parent project open none of the maven dependencies are available and so all my Java source files are full of indicated compilation errors (they're not listed in the build path for the project).
A parent project (i.e. with a pom packaging) is not a Java project, it's just there as a facility to make editing the parent pom.xml from the IDE possible (and that's already nice, importing nested projects inside Eclipse was initially not even possible).
If I open one of the sub modules as a project there are no indicated compilation problems.
That's how you are supposed to do things.
I've tried running (...)
You are not supposed to use the Maven Eclipse Plugin when using m2eclipse and this is not supported. Either use one or the other. If you decide to use m2eclipse, use Import... > Existing Maven Projects as suggested.

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