I am trying to set up IntelliJ for my Scala development after hearing how much better it is compared to alternatives. But I can't seem to run anything. The problems I'm facing are as follows:
As soon as the project is created, the console shows SBT failures
My build.sbt file shows red wiggles (compile time errors)
The confusing part is that opening the "SBT Console" view from within the IDE works fine.
The error trace is something along the lines of:
[info] Loading project definition from D:\workspaces\intellij\scala\untitled\project
java.io.IOException: The filename, directory name or volume label syntax is incorrect
[error] (*:update) java.io.IOException: The filename, directory name or volume label syntax is incorrect
Would anyone please know what can cause this? I have tried deleting the project and creating a new one but the problem still persists.
UPDATE
Just had a look at .sbt\boot\update.log and something seems fishy. Is it just me or the sbt.ivy.home is completely borked?
impossible to define new type: class not found: org.apache.ivy.osgi.obr.OBRResolver in [] nor Ivy classloader
impossible to define glob matcher: org.apache.ivy.plugins.matcher.GlobPatternMatcher was not found.
setting 'jline.esc.timeout' to '0'
setting 'sbt.ivy.home' to 'D:\software\installed\sbt\.ivy2 -Divy.home=D:\software\installed\sbt\.ivy2'
setting 'java.runtime.name' to 'Java(TM) SE Runtime Environment'
I have finally managed to hunt down the root cause. The errors were due to rogue environment variables set in my profile related to SBT (specifically SBT_OPTS). Once I deleted all of them and started with a clean slate, things started working on expected.
Related
I have recently revisited a project I have not worked on in over a year. Yesterday I was able to successfully run the REST service with no problems. Today while I was refactoring the location of certain controllers in this project I started to encounter errors related to controllers could not be found within a given package.
My routes file that looks like this:
UserController is defined as such:
However; when trying to compile this project, I receive a list of errors like: (redacted most, only included one controller for sample)
type UserController is not a member of package com.jkdev.controllers
[error] POST /users com.jkdev.controllers.UserController.createUser
Additionally, my Binders are no longer being detected by the routes file as well, so I am seeing errors like: [error] /Users/...../Developer/cashflows/metadata/conf/routes: object binders is not a member of package com.jkdev.
Like I mentioned, yesterday this was working, so I tried reverting to that commit and rebuilding, but this issue persists.
I have attempted to delete all target directories and recompile, ran sbt clean; cleanFiles. All of which provided nothing of value.
Overall this feels like a build error; but I changed nothing about the build file so I have no idea where to look next
The problem was:
I updated the intelliJ SBT preferences to use sbt shell for all builds,tests,runs, etc.
After deleting all of the ./target directories, doing SBT compile and run did not reproduce the target directories for my projects.
After updating IJ SBT preferences to not use SBT shell for builds; I was able to re-compile w/ IJ and reproduce the target directories.
Doing sbt run afterwards successfully launches the server.
I have a sbt project using FlyWay. It's disabled in most projects because we're only running the evolutions from a specific project.
So I have something like this:
lazy val master = project
.disablePlugins(FlywayPlugin)
.aggregate(common)
.dependsOn(common)
The project works fine. It compiles, works, tests pass, etc.
Now I want to add Twirl, so I do this (in addition to plugins.sbt of course):
lazy val master = project
.enablePlugins(SbtTwirl)
.disablePlugins(FlywayPlugin)
.aggregate(common)
.dependsOn(common)
And I end up with this error:
[error] sbt.AutoPluginException: Error determining plugins for project 'master' in /opt/app/master:
[error] Contradiction in selected plugins. These plugins were both included and excluded: org.flywaydb.sbt.FlywayPlugin
[error] Use 'last' for the full log.
Which I don't really understand because I didn't change anything about FlyWay.
What could cause that?
This is a known problem. FlywayPlugin gets automatically enabled on all (sub)projects and when you try to disable it, it causes the conflict.
See sbt/sbt#1926. Citing #jsuereth:
Yeah, this is a known issue in our logic system (and the translation of enablement/disablement into it). I'm working on a mechanism to fix it.
PRs welcome if you have time.
There is also an open issue in the Flyway repository: flyway/flyway#1329 which suggests not to enable it automatically. But so far there is no solution or a workaround there.
I am trying to write a Play 2.3.8 application in Scala, managing it via sbt but editing it in Eclipse. I worked round one problem, but this seems to introduce another, and cannot work out how to solve it.
I set up the project using the exact instructions to Create a new application without Activator (except I also add
scalaVersion := "2.11.6"
to build.sbt), then I cd to my project directory, type sbt and once in sbt I type eclipse. Then I open Eclipse and happily import the project.
Now I create a simple template (app/views/Application/index.scala.html) and a controller which calls it (app/controllers/Application.scala). When I go into sbt and type run I can happily open my web browser at localhost:9000 and my populated template appears.
All is good apart from one problem (the first one). When I open up Application.scala in Eclipse I get a wiggly red error line saying "object Application is not a member of package views.html". I solved that using Nick Cooper's answer elsewhere on Stack Overflow. He said to go to Project > Properties > Java Build Path > Libraries > Add Class Folder... and then add target/scala-2.11/classes_managed. That makes the error go away. But I don't want to manage Eclipse's settings directly; I want to manage everything via sbt. So by trial and error I found that I can add this line to my build.sbt file...
unmanagedJars in Compile += ( baseDirectory.value / "target/scala-2.11/classes_managed" )
...and now I can type sbt followed by eclipse and Eclipse's config is generated correctly, with no wiggly red line errors.
But this creates a second problem. It turns out that by introducing that line into build.sbt the application no longer runs. Specifically when I go into sbt, type run and open localhost:9000 I get a NoClassDefFoundError exception in my sbt console:
java.lang.NoClassDefFoundError: controllers/Application$
at Routes$$anonfun$routes$1$$anonfun$applyOrElse$1$$anonfun$apply$1.apply(routes_routing.scala:51) ~[classes_managed/:na]
at Routes$$anonfun$routes$1$$anonfun$applyOrElse$1$$anonfun$apply$1.apply(routes_routing.scala:51) ~[classes_managed/:na]
at play.core.Router$HandlerInvokerFactory$$anon$13$$anon$14.call(Router.scala:217) ~[play_2.11-2.3.8.jar:2.3.8]
at play.core.Router$Routes$TaggingInvoker.call(Router.scala:464) ~[play_2.11-2.3.8.jar:2.3.8]
at Routes$$anonfun$routes$1$$anonfun$applyOrElse$1.apply(routes_routing.scala:51) ~[classes_managed/:na]
Caused by: java.lang.ClassNotFoundException: controllers.Application$
at java.net.URLClassLoader.findClass(URLClassLoader.java:381) ~[na:1.8.0_40]
at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[na:1.8.0_40]
at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[na:1.8.0_40]
at Routes$$anonfun$routes$1$$anonfun$applyOrElse$1$$anonfun$apply$1.apply(routes_routing.scala:51) ~[classes_managed/:na]
at Routes$$anonfun$routes$1$$anonfun$applyOrElse$1$$anonfun$apply$1.apply(routes_routing.scala:51) ~[classes_managed/:na]
[error] application - Error while rendering default error page
scala.MatchError: java.lang.NoClassDefFoundError: controllers/Application$ (of class java.lang.NoClassDefFoundError)
at play.api.GlobalSettings$class.onError(GlobalSettings.scala:148) ~[play_2.11-2.3.8.jar:2.3.8]
at play.api.DefaultGlobal$.onError(GlobalSettings.scala:206) [play_2.11-2.3.8.jar:2.3.8]
at play.core.server.Server$class.logExceptionAndGetResult$1(Server.scala:63) [play_2.11-2.3.8.jar:2.3.8]
at play.core.server.Server$$anonfun$getHandlerFor$4.apply(Server.scala:73) [play_2.11-2.3.8.jar:2.3.8]
at play.core.server.Server$$anonfun$getHandlerFor$4.apply(Server.scala:71) [play_2.11-2.3.8.jar:2.3.8]
You can see the entire (tiny) codebase on Github.
All the class files seem to be all there, and in exactly the same locations, regardless of whether or not I include the "unmanagedJars" line. It's not an Eclipse problem because it happens even when Eclipse is closed. It seems to be a classpath issue (but I can't understand why adding to a classpath should hide some classes). Regardless of that, I'd like to manage my project with sbt and use Eclipse just as the editor. What am I getting wrong?
I have found a solution through further trial and error. Instead of extending the classpath to "target/scala-2.11/classes_managed" it should be extended to "target/scala-2.11/classes". In other words the line in build.sbt should be
unmanagedJars in Compile += ( baseDirectory.value / "target/scala-2.11/classes" )
Now from sbt I can compile, test and run the application, and connect successfully to localhost:9000, and I can also open the files in Eclipse without seeing error lines.
I still don't know why the NoClassDefFoundError really occurred in the previous setup, but that's a problem for another day.
I am using activator but I guess it might be the same.
So, Eclipse does not really like structural changes in a Play project or adding/removing libraries (via libraryDependencies, etc) and displays red squiggly things everywhere. This is how I solve them:
activator clean compile
If I have added/removed libraries, I run
activator eclipse
so that Eclipse gets the changes.
It works everytime. Clean, clean, clean. I actually found this solution somewhere on the Net a while a go but cannot remember where, sorry.
EDIT
And refresh the project in Eclipse!
Attempting to sbt compile a branch of my project ENSIME (experiment if you're interested) under Java 6 is giving a bizarre compiler warning:
[info] Compiling 48 Scala sources to /home/fommil/Projects/ensime-server/target/scala-2.11/classes...
[error] Class java.lang.invoke.MethodHandle not found - continuing with a stub.
[error] two errors found
[error] (compile:compile) Compilation failed
[error] Total time: 18 s, completed 03-Sep-2014 22:57:44
It works under Java 7.
Calling last reveals nothing more than the classpath of the compile (this would be equivalent to setting --debug level).
I've removed all the plugins from the project, and the problem still shows.
If I remove all my code - leaving just the build system and dependencies - with some stub scala entry points then there is no problem.
However, I can't exactly bisect my source code file because then it doesn't compile.
When the code is compiled, a grep (including binaries) of MethodHandle doesn't give any hits (although there is a jdk8 file in the tests resources, it is not relevant because the problem appears if it is removed).
It is only one (big) patch that has caused the problem (the previous commit compiles ok).
How can I debug this further in sbt? it doesn't want to give any more info
is this a known problem, or can anyone make an informed guess what is going on?
It turns out that this was caused by pulling in Lucene, which requires Java 7.
A bit of an epic message fail from sbt: there doesn't appear to be any way to get it to output anything sensible.
I successfully implemented and ran several Scala tutorials in Eclipse using the Scala plugin. Then suddenly I tried to compile and run an example, and this error came up:
Exception in thread "main" java.lang.NoClassDefFoundError: hello/HelloWorld
Caused by: java.lang.ClassNotFoundException: hello.HelloWorld
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:315)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:330)
at java.lang.ClassLoader.loadClass(ClassLoader.java:250)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:398)
After this point I could no longer run any Scala programs in Eclipse. I tried cleaning and rebuilding my project, closing and reopening my project, and closing and reopening Eclipse.
Eclipse version number 3.5.2 and Scala plugin 2.8.0
Here is the original code:
package hello
object HelloWorld {
def main(args: Array[String]){
println("hello world")
}
}
If you see this when you attempt to run as a Scala application then the most likely explanation is that your project didn't compile and no class files were generated. Please check whether or not that's the case: look in your project's output folder for hello/HelloWorld.class.
If your project didn't compile that could either be because there's an error which you've missed (and if this error isn't being reported in the Problems view that could be a bug, in which case please open a ticket on Trac) or because you've turned off automatic builds and not done a manual build of your project.
I had the same problem. Project doesn't compile but there are no errors highlighted and AFAIK the code is OK. It seems to be a problem with the Run Configurations.
Solution 1: Delete the existing Run Configuration for your object and create a new one
Solution 2: Create a new object and cut / paste all your code into that file
When running "clean" does not un-hose Eclipse, I next try saving my work, exiting Eclipse, and re-starting. That usually gets things going again, but not always. A few times I've had to update the Scala plugin with a more recent version (I'm using the latest nightly), to get things working again. I doubt that this worked because the new plugin happened to fix the bug, but rather expect that loading the new plugin gives the whole Eclipse-Scala
system a "total reset" that gets it unhosed.
I was getting this problem in a project that combined .java & .scala files.
The solution for me was:
Remove all .java files
Edit the scala code as needed so it compiles without them.
Add the .java files back in.
Edit the scala code back.
The other solutions given here didn't work for me. I tried: clean project, restarting Eclipse, closing-&-opening the project, creating a new .scala file. No joy.
I'm using Eclipse 3.7 (latest stable), Scala IDE 2.0.0 and Scala 2.9 on Ubuntu Linux 11.10.
The symptoms in my case were:
My project was working, but then it stopped compiling for no apparent reason. The IDE didn't show any compilation errors for .scala files, but there were no .class files in the output directory & I got a NoClassDefError if I tried to run anything.
If I created a deliberate error in a .scala file, that did get picked up as a compilation error.
The .java files were registering errors due to the missing scala classes.
I suppose there's probably a boot-strapping bug somewhere in the IDE plugin for .java/.scala mixes. I've done hybrid projects with this setup without problems, so it's only triggered in some situations. I don't know what the trigger is, but once triggered, there's no nice solution.
I had moved my one and only class/object/application to a package, but had not added the package declaration.
sbt compiled and ran fine; eclipse would not
Adding the package declaration at the top of the file fixed it.
Scala 2.8.3 plugin; no compile error
I encountered this error too but after doing the suggestions here (cleaning, deleting Run Configuration etc), I realized that I set the workspace wrongly that is why the class is not being found.
An indication that this is a problem is when the same error occurs when you try to compile a java project.
I encountered this error (compilation worked in sbt but failed in eclipse) when I created a new package object called "common". Deleting the package object in eclipse caused the compile error to go away. There was nothing in it.
I was using sbt-eclipse to build the eclipse project. I'm using scala eclipse 3.0.0-vfinal-20130326-1146-Typesafe.