Introduction
I have spend a lot of time to fix this bug
In our application we have a lot of generated code by cxf and jaxb which produces tons of warnings. We use the maven-build-helper plugin to add this code to our projects automatically.
By adding this enhancement, eclipse JDT enabled the possibility to set the javac -nowarn flag for specific source folders. Unluckily, by updating the maven project the flag gets lost. There are a few threads on SO where users got bugged by bug.
What I have tried so far
So i came up with a clever solution, javac has a nowarn flag. I set it to my maven-compiler-plugin and specified the directory. My maven build was fine, but my eclipse build wasn't. My research told me, that eclipse jdt does only use the maven-compiler-plugin source and target version. So my next step was to try to configure the EclipseCompiler, but this is not possible, because there is no possibility to add custom compiler Arguments in eclipse JDT.
Next Step. Inside of the .classpath file, eclipse JDT adds an ignore_optional_problems attribute for each ignored path. By updating the maven project inside of eclipse, this entry gets lost. So i started to write a maven "ignore-source-folder" plugin which should add the missing attribute. To run the plugin each time eclipse starts a build, i also created a m2e connector to refresh the .classpath file and everything should be fine.
By testing my plugin with my connector i realized, it works, but only 70% of the repetitions.
What happened?
Every time eclipse m2e/Jdt starts a new build, all classpath entries will be removed and populated again. When my maven plugin gets triggered by eclipse, a race condition starts.
So I started to analyze the code of jdt and m2e jdt. The ignore_optional_problems flag gets only once set manually inside of the patch which was provided to JDT and isn't stored somewhere else. By triggering a new build via m2e-jdt this information gets lost.
How to fix this problem
To fix this problem, some element has to be added or extended in jdt which contains all ignored folders. If a new build gets triggered and the classpath file gets newly generated by m2e-jdt this element should be checked for ignored paths. ClasspathEntryDescriptor seems to be a good place for it.
My problem
I checked out jdt and m2e jdt, but i have tons of errors inside of my IDE and i have no idea how to start. And even if I fix the code, I have no idea how to build and test it. I think my effort will be to high and we talk about 20 or 30 simple lines of code.
I am afraid if I add my results to the filed bug at eclipse, no one will care about it.
So, is there any developer able and willing to help me for this tiny job?
You need to "fix" the M2E's JDT project configurator. Probably somewhere in the m2e-core project. So, your change should obtain some kind of configuration flag from the project pom and create corresponding classpath entries for JDT.
Related
I’m using Eclipse Mars with Maven (v 3.3). When I update a dependency in my pom (change the version), my Eclipse-Maven project doesn’t pick it up, even when I right click my project, and select “Maven” -> “Update Project.” I know this because I do not see compilation errors in the Eclipse Java editor that I see when I build the project on the command line using
mvn clean install
When I remove the project from the workspace and re-import it, then things get back to normal. However this is a cumbersome process. How do I get my Maven-Eclipse project to automatically detect changes in my pom and update the project libraries appropriately?
And yes, in the “Project” menu, “Build Automatically” is checked.
When you import the project into Eclipse, use Eclipse's own built-in Maven support (aka, m2e). I recommend against using mvn eclipse:eclipse as it doesn't give the best results (as you're seeing). Maven is a build and dependency management tool, not an IDE; expecting it to manage IDE-specific stuff is silly, in my opinion (I realize the Maven team thinks differently, that Maven should be responsible for managing your IDE, but that's nonsense).
So if you have the project available on your system, delete any Eclipse-specific files (typically just .classpath, .project, and folder .settings), they were generated by mvn eclipse:eclipse and you don't want them interfering with the "proper" import process described here. Then inside Eclipse, use File > Import > Maven > Existing Maven Projects to import the project. That should result in better integration between Eclipse and maven, including automatically updating the Eclipse build path when the pom is changed.
As a quick check, after doing the import that way, you should see a group called Maven Dependencies in the Libraries tab of the project's Build Path (in Properties dialog). Like this:
If you want the Eclipse project configuration to be automatically updated every time the pom is changed, there's a (experimental) setting for that under Preferences > Maven. Be aware that doing so might not be desirable, though - as mentioned in this feature request, it's a somewhat lengthy process that touches a bunch of stuff in the Eclipse Project; doing that automatically on every pom.xml change could end up being more trouble than it's worth.
Three Mandatory checks you should do for automatic update in your classpath
Your Repository is not in-sync with your Eclipse IDE, Please check the below settings in your IDE.
Right Click your any POM.xml from your IDE and check for the Maven profile which should be auto-activated. Also offline and Force update check box shouldn't be enabled. Please refer the below image.
Always check for your user settings which should reflect your local maven settings.xml, as shown in the below figure.
After performing all these checks, refresh your Eclipse Work-space to get these changes reflected.
Eclipse should be updating your classpath. If it's not, that implies something is going wrong.
It's hard to say what the problem could be exactly without knowing more about your project's pom.xml. More information might be necessary to solve the issue, but I'll just make a stab in the dark:
Open the .project file in your project's root folder and check the ordering of builders and natures there. It might be possible that some other nature on the project is also causing maven2Nature to fail. Move maven nature up and see if that helps any.
Alternatively you might be thinking that Eclipse does not update your dependencies because it does not add some some error indicators in the project that should be there with new dependencies. If that's the case try cleaning the current project (project>clean...). Maven in Eclipse does not necessarily trigger a full rebuild when dependencies are updated.
If none of this works, closing/opening the project might solve the issue quicker than re-importing.
What you wrote, should work. Did you check this:
does "pure" mvn install from terminal see your changes in POM?
maybe some Maybe plugin is buggy, cached some dependencies in target, and mvn clean install is needed
you can run Eclipse in a new workspace, and import your project there, sometimes it helps in case of such strange problems
instead of importing Maven project to Eclipse via m2eclipse, you can try to create Eclipse files via the old mvn eclipse:eclipse and see what happens then
does it work well when you try to import your Maven project to other IDE, the free IntelliJ Community Edition for example?
As a last resort, you can delete your current Eclipse installation and install a new version. When you add several plugins, they might interfere with one another and create weird behavior. After you do that, do not import your Maven project into your workspace, but rather create a new one and copy and paste the files that you had.
I would like to be able to automatically setup our eclipse projects to Ignore optional compile problems using m2e, but I seem to run into a conflict of m2e vs maven.
If I use the build-helper-maven-plugin to add source directories, it's great - I don't have to automatically add the generated-sources/annotations to my eclipse project. But if I do that, every time m2e Updates the eclipse project (alt+f5), it removes any manual configuration I've added to the source directores (including the Ignore optional compile problems).
So currently, my workaround is to manually add the generated-sources directories to the eclipse projects so that I don't constantly get all those warnings back on generated code.
(My use case is using dagger, which has a lot of generated code, but in very different formats from the rest of our code base, is not java8 based, etc, so we get lots of format and style warnings).
One answer may be to try out the Annotation Processing in m2e, but I've had issues with that in the past conflicting with maven on the command line and other issues, and I'm not sure it would address this issue anyhow. Even the choices in the list for Annotation Processing Mode both list the deficiencies.
Can anyone think of any other workarounds, until the bug is fixed?
The bug is finally fixed in M2E 1.6.2 (1.6.2/Mars RC2).
I'll try keep this short. I have Eclipse with an installed M2E (Maven to Eclipse) plugin. I have a GAE (Google App Engine) project I'm working on. Everything is working ok apart from one really annoying thing: I have to stop/start the devserver every time I make a change.
If you have any experience with this setup then you might be able to answer this simple question?
I start the development server with "mvn appegnine:devserver" on the command line. Now I would expect that if I made changes to a *.jsp for example that those changes would automatically be updated on the devserver. Is this what happens with you?
I have noticed that if I make changes to *.jsp files under my target folder then devserver will see those changes and updates as I would expect. I think my problem lies with Eclipse not copying changes to target folder, but not sure if is even suppose to?
Does anyone have any suggestions on how I should progress investigating this? I've ran out of ideas :-/
I thank you in advance for any comments you may have.
P.s I know I can run "mvn package" to update files, but this is slow and the devserver runs out of memory after a do it twice.
This can be little painful, depending on how you want to work and which version of eclipse you're using.
Install the m2e-wtp plugin if you haven't. It's the secret sauce that makes appengine projects work in eclipse. Note this isn't m2e - but another plugin.
Install the GPE - the google plugin for eclipse if you haven't
Make sure your project is being managed by m2e as a maven project.
Go into your project properties - enable it as an appengine project using the GPE (listed under 'Google'). Don't forget to tick HRD while you're here.
Go to your project build path (Properties -> Java Build Path).
Ensure on the source tab that your src/main/resources doesnt have an ** exclusion.
Ensure on the libraries tab your have the three libraries 'JDK', 'Google Appengine' and 'Maven Dependencies' and nothing else
Ensure on the order and export tab that the appengine dependencies are above the maven dependencies.
It sounds pretty ridiculous - i'm not really sure why its still so painful, but that is a good recipe for success. Once that's done, this should allow you to run in debug from eclipse itself, with hotloading of code, jsps, css, scripts etc. I've had this work in helios, indigo and juno.
You can read more about the m2e-wtp setup instructions here. They refer to GWT but it's the same for appengine (I'm not sure why the emphasis on using GWT on GAE) because its actually about the correct setup of GPE and Maven.
You will also find that you may need to repeat some parts of step 5 pretty frequently - if your app isn't loading properly take a quick look to ensure that your resources haven't been excluded. This happens when you update your project configuration using the m2e plugin.
The wtp-m2e plugin updates the target folder as resources modified - so this should also resolve your issues running from the command line, but i can't vouch for that - I prefer to run straight out of eclipse.
I have the same problem as you, however I resolved with other way. I use FileSync plugin (which can be found in the market place).
With this plugin you configure an input directory (webapp) and output directory (target).
Any change made to the webapp will be passed to the target.
I have helped too.
You can use rsync like this:
rsync -r --existing src/main/webapp/ target/ROOT
where "ROOT" is the project build finalName.
The below point worked for me.
Ensure on the order and export tab that the appengine dependencies are above the maven dependencies.
I'm working with project in intellij IDEA IDE based in maven. I can perform all maven goals but IntelliJ is showing a lot of errors in the source code like bellow:
Everything worked fine a few hours ago. I don't understand why the IDE continue
showing errors. When I rebuild or compile the entire project (CTRL + F9) or a single
scala class I always receive a success message like that:
I already had configured scala plugin before, so I don't know what is happen.
thanks for your help
Sometimes the IntelliJ cache gets corrupted. You can fix this by the following:
File > "Invalidate Caches / Restart"
After choosing "Invalidate and Restart" when prompted, IntelliJ will restart and rebuild its cache.
If IDEA has lost track of obviously correct types such as Database or DateTime it probably means the configuration of the project is wrong or corrupted. Most commonly it does not have the required 3rd part dependencies such as Joda Time.
If you're not already doing so, define your project solely in SBT and use the sbt-idea plug-in to produce your IDEA project definition. Then whenever you change the project dependencies, re-run gen-idea to regenerate your IDEA project files. No muss, no fuss.
There are many bugs raised in jetbrains's bug tracker for this. I suggest you raise some bugs or vote for existing ones.
It loos like the problem you have is with the type aware highlighting which is worse than useless.
thanks for your responses.
I solved this problem importing the project again.
I am working on an RCP project based on eclipse. It has been working fine but recently I thought I'd upgrade it to use a new eclipse version (3.2 -> 3.5).
After a bit of trouble, it was running on the new platform. Then I did something. Don't know what. The end result is that I'm now getting a classpath error when one of my plugins (A) tries to access a class in one of the dependent plugins (B) (also one of mine).
As far as I can see, Plugin A has Plugin B in its' dependency list and the compiler shows no errors. To test, I created a new Plugin C with one class and accessed the class from Plugin A. That works fine.
Does anyone have any hints for troubleshooting such issues? A checklist of settings to check? I've been struggling with this for hours and getting nowhere! Particularly frustrating as it was working until I changed something!
Thanks
Update
I should also say that the project is quite old and uses the plugin.xml and not the manifest. Could this be a problem? Is there a way to upgrade?
Some ideas:
Clean-and-build every project (maybe after a restart of Eclipse)
Check, whether the required packages are also exported
Check the Error log, maybe there is some unloadable plug-in, etc.
Check the Run configuration, whether every required plug-in is present there
If the problem does not happen in a Runtime workbench, but in an Exported RCP app, then check whether you compile the project with the same settings during export than in Eclipse
I hope, something helps about these.
You can try the following in your run configuration:
In the Main tab check Clear (workspace) under Workspace Data
In the Configuration tab check clear the configuration area before launching under Configuration Area
This helps me every time I encounter some strange ClassNotFound errors.
If I understand you correctly you have no compiler errors but when you run you get class not found exceptions? You could try PDE Tools > Update Classpath from the project's context menu to see if you declared any dependencies outside of the MANIFEST.MF file, which would result in compiling code that fails at runtime.
I developed for RCP quite a long ago, but if I'm not wrong, since 3.4 or 3.5 you have to declare in the plugin configration which packages/classes are exported for dependent plugins and which are not.
This is unlike the old convention of using 'internal' in the package to mark non-exported packages.
Since you have plugin.xml from very old version of eclipse, it might be the problem, as exported resources from one plugin to another were not enforced in Eclipse RCP 3.2.
One more complement, hope it helps.
Open plugin.xml, check "build" tab, see how "binary build" are configured. It affects which files will compiled and exported.
See binary build here : http://help.eclipse.org/indigo/index.jsp?topic=%2Forg.eclipse.pde.doc.user%2Fguide%2Ftools%2Feditors%2Fmanifest_editor%2Fbuild.htm