I have exactly the same problem as in this question: Eclipse: Using "Open Declaration" ... in a Scala project
However, I'm using the latest Scala IDE in version 3.0.2 (I have downloaded the Eclipse bundle from the site), and I would assume such basic functionality works by now, and apparently it's me who have something misconfigured.
I have created a new Scala project. Then I open some standard library class/trait/whatever, let's say scala.util.parsing.combinator.JavaTokenParsers. The source is neatly displayed, but when I try to show class hierarchy, I get the message: The resource is not on the build path of a Java project.
Also, searching for references etc. won't work.
I guess it is a matter of properly configuring the build path? Or maybe I should somehow attach Scala library sources to my project? But I can see the source, so aren't they attached already?
Here is the snapshot of my project configuration:
UPDATE:
By playing a bit with setting/resetting build path stuff, I managed to get rid of pop-up warning but the class hierarchy comes up empty and when searching for references I get only hits from my own sources, nothing from standard library.
In another workspace I also tried randomly adding and removing scala-library jars and got it work almost, but the type hierarchy comes up only with super-classes, without any sub-classes (which renders it quite useless). Searching for references works ok though.
Funny thing, I cannot make it work in my original workspace...
Gotta love Eclipse.
Your build path is not configured properly.
If you take a look under Scala Library[...] you have scala-library.jar we can only see one top-level package scala. There should be numerous other packages besides that. (Ruled Out)
I would recommend you follow these steps
Right-click project, build-path, Java-build-path, Libraries and make sure that the correct library is referenced there.
If it is the one you need, Try to remove this library and add it again, then clean and re-fresh the project. Also try this step in a fresh workspace.(something must have messed up this workspace )
Lastly. Goto the path D:\Eclipse For Scala\configuration\org.eclipse.osgi\bundles\286\1\.cp\lib and verify the sizes of the jars there. There should be 6 jars there and the size of scala-library jar should be around 6.8M. If size is smaller, consider re-downloading
Related
My problem is best described with a screenshot:
As you can see, there is a org.virtuslab:unicorn-core_2.11 dependency loaded in my SBT/Scala project. The jar file with corresponding sources is available as well. For some reason, Intellij Idea decided to ignore the available source file Table.scala and uses the .class file instead. Clearly, all other files are okay.
Obviously, without the information contained in the .scala file, Intellij is not able to properly analyze my code and I'm getting Cannot resolve symbol BaseIdRepository errors (and similar) all over my project.
I manually checked the source package and the Table.scala file is there and seems alright. Plus this worked flawlessly until two days ago. I don't know why it broke down. I tried to revert my project using git to an earlier version when this was still working, but no luck.
I tried to both downgrade and upgrade the library, I tried to remove it and add it again, I tried create a completely new project based on existing sources, but once again, no luck.
Just for the record, I'm able to compile and run my project. The only thing that might be related is this warning that I get when compiling the project:
[warn] /home/tobik/scala/payola-viz/src/app/model/appgen/repository/UsersRepository.scala:7: Could not find any member to link for "BaseIdRepository".
I got an update for the Scala plugin which seems to fix this issue.
In case you experience similar problems, this temporary solution worked for me: I added the unicorn sources directly to my code base and manually removed it from the project libraries. I got rid of the errors and it still compiles as the library remains as a dependency inside built.sbt. To avoid polluting my project, I added the included sources to .gitignore. The workaround broke after a while but all I had to do was repeat the procedure again.
I have an infrastructure project that contains other projects as resources. (Because it compiles them on the fly). One of those contained projects is deliberately one that fails to compile.
This makes the entire project show in eclipse as "with errors".
How can I make sbt-eclipse configure eclipse such that e.g. anything under src/main/resources/foo should be ignored?
Of course this isn't exactly the scenario eclipse was built for, but might there be some clean way around it? as much as it matters, sbt itself does not try to compile these resources.
If not, maybe a way to tell eclipse to not even load source
directories under src/main/resources?
Thanks!
I followed the getting start video on Jetbrains website to setup IntelliJ IDEA 13.1 Community Edition to work with Scala. Scala plugin v0.36.431 had been installed. While I created a new Scala SBT project with wizard, there was no src/ directory structure generated in the project. Only two sbt files were generated:
scala-course/
├── build.sbt
└── project
└── plugins.sbt
From the video and other document I know that there should be a src/ directory structure, including src/main/scala, src/test/scala, etc. sbt uses the same directory structure as Maven for source files by default.
I can create those folders manually and mark it as source root. However it is trivial. So my question is: Why IntelliJ IDEA new project wizard doesn't generate the directory structure as said in document? Was I doing something wrong? I checked the preferences and couldn't find anything that seems related.
Normally it should create these folders automatically. It may take a while though - it takes couple of seconds in my case.
When creating project make sure you have selected Scala -> SBT, then proceed with the wizard.
Once the Finish is clicked, the project will be loaded. This part takes couple of seconds, and I can see no src/main/scala nor src/test/scala generated until it's done. Observe the bottom of the screen to see when it's done.
Once the process is finished, you'll see the folders.
If that's not the case, check the settings. You should have the Create directories for empty content roots automatically checked. You may want to check Use auto-import to automatically propagate changes in the build.sbt.
After changing the settings (if the change is required) you may need to refresh the project, as seen in picture below.
This can also happen if you do not have a JDK selected. For some reason you no longer get the option to select an SDK so you must make sure you have configured this before hand. To fix this do the following:
From the welcome screen, go to
Configure -> Project defaults -> Project structure and add the jdk.
Source:
What's the reason for "Error:Cannot determine Java VM executable in selected JDK"?
Thanks to lpiepiora, with his hint I find out the reason.
Because my sbt is newly installed, there is nothing in ~/.ivy2/cache/ and ~/.sbt/boot/. sbt needed to download required dependencies from repositories on network. It happened that my proxy to internet had something wrong, download stuck.
And also need to notice that, if quit IntelliJ IDEA when sbt is running in background, the next time you'll get error of waiting for some lock file. Have to remove the lock file on filesystem and restart IntelliJ IDEA again.
After fixed the network problem, everything work as promised. It requires several minutes, depends on network speed, to download required jar files. After finished, the src/ directory structure is created.
I followed the instructions in this thread but I had a java crash in the final phase in sbt with the configuration bellow and I think this info maybe useful:
The problem happened with IDEA 2016.2, sbt 0.13.8 (I tried later to import using 0.13.12 but the crash was the same), scala 2.11.8 and ubuntu 16.04.
The only way I could make it work was to use java 8 instead of 9.
error: error while loading package, Missing dependency 'object java.lang.Object in compiler mirror', required by /home/jbamaral/.sbt/boot at xsbt.boot.Boot.main(Boot.scala)
...
stack log here
...
[error] scala.reflect.internal.MissingRequirementError: object java.lang.Object in compiler mirror not found.
I am already using an open source GWT project (iServe) and I would like to integrate into it another open source GWT project (PetalsBPM), by which I mean being able to call it and reference its methods.
I have imported iServe in Eclipse (it has multiple modules) as separate Maven projects referencing its other and can run it successfully through Runas -> Web application in development mode.
If I do that and run the other project through the console as mvn gwt:run, I call initiate PetalsMBP through iServe. However, that means that the two programs have to run as is, without communication with each other.
I have also imported the second project into eclipse as a java project successfully (converting into a Maven one causes problems - various lifecycle configurations ones), but whenever I try to add to to iServe through Properties -> Java Build Path -> Projects, although it does not cause any errors immediately, I cannot launch iServe anymore. It produces the following error:
"Exception occurred executing command line.
Cannot run program "C:\Program Files\Java\jre7\bin\javaw.exe" (in directory "C:...iserve-sal-gwt-1.0.0-SNAPSHOT"): CreateProcess error=206, The filename or extension is too long"
Are my problems related to the fact that PetalsBPM is not a Maven project in Eclipse (I doubt it)?
Am I doing something wrong, i.e., this is not the way to reference a project from another one? should I add a reference to the first project's (iServe) gwt.xml file?
Is there a way to do what I want without having to wrap the second project as a jar and calling it from iServe? I would prefer not to, since producing a jar every time I make a slight change is not exactly efficient!
P.S: The second project is a regular GWT project with an entrypoint, not just a module. Should I remove this?
UPDATE: Trying to figure out the source of this error, I attempted to simplify the problem, so I performed the following moves:
I created two new simple GWT projects and tried to reference one
from the other. Worked fine
I referenced the project I actually want
to use (PetalsBPM) from the simple one I just created. Also works
fine.
I referenced the new simple project from the original one I
want to use (iServe). Also works fine.
Tried doing what I actually
want to do, copying the settings from 2&3. Produces the same error
"CreateProcess error=206, The filename or extension is too long" if
I reference PetalsBPM (does not when I remove it from the referenced
projects)
So, I tried switching workspaces. I created a new workspace in C:\, and moved the actual projects there. Still it did not work. :(
Any more ideas?
I met the same type of error "Create Process, error=206, path too long etc." a hundred times.
Then, I found a solution/explanation in google-groups, it solved my problem.
I post the content and link as it might help others.
This website (StackOverflow) really helped me a thousand times.
Thanks to you all !
solution/explanation :
(Response from Stephen Johnson)
(...) if you're using eclipse plugin go to Project | Properties, choose
Google \ App Engine \ ORM and only include directories that you have
classes that you want enhanced. By default it does the entire project
so that includes a lot of needless files. (...)
Link :
original post # google-groups
Read the exception message again. Somewhere along the way Maven is generating a path that is too long for (some) Windows API to handle, try moving your workspace to a directory straight below C:\.
I just tried "skolima" reply and it worked for me. In Eclipse I clicked File->Switch Workspace.
Three things to note:
After I created the workspace in "C:\workspace" I had to update my Project->Properties > Java Build Path > Libraries > Add External JARs...
I'm using Windows 7.
I'm using "Eclipse Java EE IDE for Web Developers"
I hope this others.
Note: This is an exact repost of the same question on the Scala-IDE mailing list, where I got zero reply and gave up waiting after 5 days.
I'm writing a Scala Compiler Plugin. It's currently called
scalawrapper (but I might find a better name later). I have the
Typesafe Stack installed, and I put my plugin in it under:
C:\Program Files\typesafe-stack\misc\scala-devel\plugins
Now I can call scalac like this:
scalac -classpath ... -Xplugin-require:scalawrapper test\...
and it finds and uses my plugin automatically.
Unfortunately, I just can't get the Scala-IDE to use it. I always get
Missing required plugin: scalawrapper. In the "Project Properties
\Scala Compiler (Use Project Settings)\Advanced" tab, I have entered
scalawrapper in the Xplugin-require field, and that works, since I get
the error. But nothing I can type in Xpluginsdir seem to have any
effect.
I have tried the absolute path given above, have tried with forward
and backward slashes, have tried a temporary directory without spaces
in it, have tried relative to project directory, have tried relative
to workspace. It just will not use anything. I should also note that
is is not specific to my own plugin, as I tried to use the ScalaCL
plugin before in a previous version of the Scala-IDE, and failed for
the exact same reason.
I have just updated today (15.10.2011) and so should have the latest
version (it seems I can finally explicitly set the indentation to 4,
but maybe I just overlooked the setting in the past).
Can someone tell me what it actually expects, and what is uses as
default when I don't put anything in Xpluginsdir?
The Scala IDE uses the presentation compiler, not the compiler that you've installed. To use a plugin, with Scala IDE, you need to specify it in the preferences in Eclipse.
Try Windows->Preferences->Scala->Compiler. See the Advanced tab. The paths are relative to the workspace.
EDIT: When I say relative to the workspace, I mean the actual workspace directory under which the .metadata is stored ($workspace_loc). I have a project where project files including the source code is stored in one directory and the workspace is elsewhere, i.e the $project_loc (c:\code\project\source) is different from the $workspace_loc (c:\code\project\workspace). The directory that you specify in the compiler parameters is relative to the workspace ($workspace_loc).
To find out if you have a similar setup, go to the project and select Properties->Resource->Linked Resources.
I created a directory under $workspace_loc called plugin and placed the jar file in there. Under Windows->Preferences->Scala->Compiler Advanced tab I have
Xplugin = C:\code\project\workspace\plugin\xxx-0.0.1.jar
Xplugin-require = xxx
Please note that you can specify the plugin in the project properties as well, but it still uses $workspace_loc. The above configuration works for me.