Using IntelliJIdea 12, i downloaded the Scala plugin and created a HelloWorld application.
The following import seems odd. Why does IDEA not recognize this to be a Scala Application? Is my setup incomplete?
I checked to see where does my compiler points to and got this. Don't really see a way to navigate IDEA to my scala installation.
Please advise.
When creating a new Scala project from the wizard IDEA can download and configure everything for you:
Settings can be changed later in the Scala Facet:
and in Compiler:
Libraries configuration:
Code and imports completion is available from the Scala library:
You need to add Scala as a framework for your project.
To do this, right click on the top level directory in your project, choose "Add Framework Support..." and select Scala. Then Scala will be added as a "Facet" of your project.
Here is a good page with more info:
IDEA Scala Project Configuration Explained
I got around this by downloading the Scala library from scala-lang.org, unzipping it and then pointing the project to it. It worked fine after that. But of course, I'm an eclipse guy so perhaps someone else might be able to give you a better automated (?) solution. Here's what my project looks like in Module Settings -> Libraries:
Related
I just downloaded the plug in for Scala in IntelliJ and have created a project but now have various errors I read that the problem can be that I am missing a library. But when I try and go to project structure -> dependencies to add a library I have no clue where in the files to look for a library.
The errors are really simple but I can't seem to figure it out.
Any suggestions would be helpful :)
Here's everything you need to properly set up Scala plugin in Intellij. Furthermore your code has several errors:
Are you sure you created a Scala project (when you did File->New->Project)? This looks to me like a Java project? That class file looks to me like a Java class not a Scala class (that's why you're getting compilation errors on def but not public class).
1) value is not defined anywhere, of course it will throw a compilation error
2) classes in Scala are by default public, you do not (cannot) mark them as such
You can save yourself a lot of trouble by creating a simple SBT project that specifies all of your dependencies, etc. and then just pointing the IDE at that. Then when you change build.sbt, IntelliJ IDEA will notice that and update itself automatically. Plus, your build.sbt gets checked into your code base so that anyone you are collaborating with sees your changes to the dependencies. And the project can be built in batch mode using sbt compile and friends.
The following page talks about IntelliJ IDEA's "SBT Import" feature:
https://confluence.jetbrains.com/display/IntelliJIDEA/Getting+Started+with+SBT
Scala source files end in .scala, not .java. Try renaming Counter.java to Counter.scala. This should improve things a lot.
Wanted to start using intellij idea for my scala project and stumbled upon this link - http://theyougen.blogspot.in/2010/01/how-to-setup-maven-scala-project-with.html
Followed the steps, created a new Scala Project (without sbt), Create a new Scala Class, and copied the HelloWorld code from Scala tutorial - http://www.scala-lang.org/old/node/166.html
Went to Build > Make Project and got following error -
No compiler library set for module.
Went to File > Project Structure. On the left side, clicked on facets, and noticed that Under Compiler Compiler Library was set to none. And there is no other option available in the drop down.
How to solve this?
PS: Googled a lot, could not find any clue on how to fix this.
If on MAC
Download scala from http://www.scala-lang.org/download/
Extract it to some-location/scala
In Intellij Idea go to File, Project Structure and select Global Libraries.
Click on + button
Select Java
Give the path to some-location/scala/lib
Click ok
Apply and OK.
Go to File, Project Structure, facets. You will see a new Scala library in drop-down.
I'm trying to get started with the examples here. I'm trying to set up my dev environment using Scala IDE (Eclipse).
So far,
I have downloaded lms, built it using sbt and added the generated jar library to my eclipse project.
I'm trying to write this bit of the code sample provided.
val snippet = new DslDriver[Array[Int],Array[Int]] {
def snippet(v: Rep[Array[Int]]) = {// Continues
However, DslDriver isn't found inside the scala.virtualization.lms package. The library is being found so it's not a problem with the build path.
I have also installed the scala-virtualized plugin to my Scala IDE.
Perhaps this is an eclipse issue where it can't find the necessary classes? Should I switch to coding using an editor and building using sbt?
Any help would be appreciated. Thanks in advance
I'm not familiar with lms but have you tried using sbteclipse to set up your project?
I'm not sure if you found a solution to your question, but the DslDriver class is defined in the dslapi.scala file.
Checkout the whole tutorial folder.
I am new to intellij idea and I decided to shift because I found the scala plugin on eclipse to be annoyingly buggy.
But, intellij idea, which I have heard to be very good, looks difficult to use.
I looked through the getting started with scala plugin page but couldn't find documentation specific to the latest version of lightweight ide of intellij idea 11 for scala.
I have created a project and made a hello world object in scala but I am not able to run it.
On trying to run it, it shows the scala interpreter (type in expressions to get them evaluated).
I don't exactly understand what changes to make in the project structure to be able to run scala code. As of now, i added the jsdk to point to my $JAVA_HOME and the scala library is also added. The scala plugin is also working in that syntax highlighting etc is fine.
The intellij idea user interface is also not very friendly and I don't get how to run the code. What modules am I supposed to add? Also, does compiled scala code run with jvm?
I'll be grateful to anyone who helps out.. I have been putting off writing scala code because I am not able to find THE IDE.
EDIT: Thanks for all the help! I am now able to run a basic scala program. I am trying to add external jars. What is the equivalent of doing Project right click-> Configure Build Path -> adding external jar files in eclipse? I tried adding "dependencies " under modules tab in project structure. It's adding the jar files but somehow the classes in the jar files are not still recognised.
With the Scala plugin installed either
A. Create a new project and select the Scala facet in the creation phase. It will create the Scala library lib and Scala compiler lib and setup the facet for you
B. If you already have a project. Go to Project Structure -> Modules and right click the module and go Add facet and add a Scala facet. Now you need to add scala-library.jar as a library of the module and go into the Scala facet and point it to a library containing scala-compiler.jar
Some more information
this is what your module should look like under project settings
select the Scala facet and this is what you should see (Library name for the compiler is unimportant as long as it says (version xxx) next to the library name
these are the jar files in my scala-compiler lib
and these are the jar files in my scala-library lib
With everything setup like that you should be able to right click -> new Scala class (Select object from the dropdown) in a source directory and add
def main(args:Array[String]) {
println("Hello world")
}
then right click on the class and select Run Classnam.main() and IntelliJ will setup a run configuration for you.
Edit: I can see someone posted somewhat the same I want to say here. I hope this can give a few more in-depths hints, so I will post it anyway :-)
If you would like to run Scala native in IntelliJ (I shifted to IntelliJ and still can't get my hands down) you need to make sure a few things are in order. Most of this happens under File -> Project Structure which requires you to create a project (when you get a hang of it, it is much more logical than Eclipse -- and Netbeans for that matter). I am also assuming you have selected a jdk, but this can also be done in the Project Structure.
Now, to Scala:
Make sure you have the Scala plugin. Visit the Settings (File -> Settings; can also be found at the start-up screen) and locate 'Plugins' (for me it's nr. 8 from the bottom). Under "Browse Repositories" you should be able to search for "scala", find and install a plugin.
1 A. If no plugins pops up you are probably using a version of intellij where scala is not (yet) supported. If that happens you can go to the homepage for the plugin and download the nightly build.
Import Scala as a library in File -> Project Structure -> Global Libraries. Click the plus sign, select Java (Scala is a Java-lib), browse to your scala-dir (which can be downloaded here: http://plugins.intellij.net/plugin/?id=1347) and select the lib directory. Press ok and you should see the library popping up on the list.
Make sure the facet (Scala framework) is in place. Goto File -> Project Structure -> Facets. Click on the plus-sign and find Scala. A sublink should appear (if not double-click the Scala link). Clicking the sublink make sure you have selected a compiler before continuing. This should be provided by the modules selected before. I normally use FSC (Fast Scala Compiler) but it's probably a good idea to test the basic settings before experimenting.
Make sure the Scala Module is in place. In Project Structure -> Modules click on the module you want to compile in scala and click the plus icon above and select Scala. Again be sure to select a compiler library.
If you want to, setup configurations for the compiler under the facet
Use sbt with sbt-idea plugin to generate idea project files for complex projects.
Or
For simple projects.
Add scala nature to the project, and you can right click and run any file extending App.
A good walk-through on how to set up a Scala project in Intellij is located here:
http://sonyarouje.com/2011/03/18/running-scala-in-intellij-idea-10/
I recently gave up trying to use Scala in Eclipse (basic stuff like completion doesn't work). So now I'm trying IntelliJ. I'm not getting very far.
I've been able to edit programs (within syntax highlighting and completion... yay!). But I'm unable to run even the simplest "Hello World". This was the original error:
Scala signature Predef has wrong version
Expected 5.0
found: 4.1 in .... scala-library.jar
But that was yesterday with IDEA 9.0.1. See below...
UPDATE
Today I uninstalled IntelliJ 9.0.1, and installed 9.0.2 Early Availability, with the 4/14 stable version of the Scala plug-in.
Then I setup a project from scratch through the wizards:
new project from scratch
JDK is 1.6.u20
accept the default (project) instead of global / module
accept the download of Scala 2.8.0beta1 into project's lib folder
Created a new class:
object hello {
def main(args: Array[String]) {
println("hello: " + args);
}
}
For my efforts, I now have a brand-new error :)
Here it is:
Scalac internal error: class java.lang.ClassNotFoundException [java.net.URLClassLoader$1.run(URLClassLoader.java:202), java.security.AccessController.doPrivileged(Native Method), java.net.URLClassLoader.findClass(URLClassLoader.java:190), java.lang.ClassLoader.loadClass(ClassLoader.java:307), sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301), java.lang.ClassLoader.loadClass(ClassLoader.java:248), java.lang.Class.forName0(Native Method), java.lang.Class.forName(Class.java:169), org.jetbrains.plugins.scala.compiler.rt.ScalacRunner.main(ScalacRunner.java:72)]
FINAL UPDATE
I uninstalled 9.0.2 EA and reinstalled 9.0.1, but this time went with the 2.7.3 version of Scala rather than the default 2.7.6, because 2.7.3 is the one shown in the screen-shots at the IntelliJ website (I guess the screen-shots prove that they actually tested this version!). Now everything works!!!
I have encountered the same scalac error when trying to run a Scala project in Intellij Idea 9.0.2 and I've managed to find a solution by chance :). These are the steps I took in creating the project and running it.
I have created a Scala project in Intellij Idea 9.0.2 final (it was released today). I have installed the Scala plugin, restarted the IDE and created a new Scala project (with the name "TestScala") with scala-2.8.0.Beta1 as project library. Once the project is created and the scala libraries downloaded, I have created a Test.scala file with the following content:
object Test {
def main(args:Array[String]){
println("hello")
}
}
After that, I created a launch configuration ("Edit Configurations"), choosing the "Application" template. I set as main class Test and choose the project name ("TestScala") in the "Use classpath and JDK of module" combo box. When I run the configuration I get the same error as you reported ("Scalac internal error: class java.lang.ClassNotFoundException") .
Now comes the freaky part :). I right click on the project, choose "Module Settings", have a look on all settings but I don't change anything . Click "apply" and "ok", try to run configuration again and it works :) .
I use Intellij Idea 9.0.2 the final release (build 95-66); Ubuntu 9.10 and JDK 1.6.0_18. I also have to mention that I had a JDK configured in Intellij, otherwise there is an extra step to configure it.
UPDATE:
When checking the setting of the module, one needs to click on the Module->Scala and Facets->Scala (expand it and click on Scala(ProjectName)) . Both of these settings are about the scala compiler and scala library location. I would guess these values are not properly set when the project is created but are saved once the user touches them and saves the settings.
To answer your question, it's difficult to get a working IDE for Scala for two reasons:
(a) Scala is only just beginning to reach a wide audience and
(b) due to (a), there is no business case for spending time on a Scala IDE.
Also, if you are old enough to cast your mind back and young enough to still remember, you would know that for the first five or more years of Java, we were stuck with okay-ish tools like JBuilder that did little more than compile your code when you said so - no error highlighting, no auto-importing, and the word refactoring didn't even exist. If you want to pioneer, you need to be prepared to cut some of the road yourself, or at least bush-bash.
I know it won't help you, but I have successfully used IDEA for Scala on Linux, Mac and Windows. I typically have the Scala SDK installed somewhere locally and point IDEA at that rather than using the 'download' option.
Presently, I am mostly using an EAP version of IDEA 9 on Mac OS X with Scala 2.8.0.Beta1-RC5 and it's working well (except that fsc doesn't seem to worked with mixed sources).
You could try your luck over at the IDEA Scala Plugin Discussion Forum, though I haven't had a great lot of responses to my own postings there.
Installing the plug-in is prerequisite one.
The next thing you should do is define a library (global or project-specific; I use global) that holds the Scala library and compiler JAR files (at a minimum, that's scala-compiler.jar and scala-library.jar). Adding source JARs and a documentation JAR or URLs is a good idea, too. Then make this library a dependency of any modules in your project that include Scala code.
Lastly, find the Scala facets in those modules and de-select both check-boxes there.
I just did a fresh install and had exactly this same problem myself.
It turned out that, because I had created the file in the root package, IDEA had added a package statement at the top with naming a package. I assume that this then got compiled as "package object Main" - valid syntax in 2.8? Anyway, I deleted the line that said package and it all worked fine.
I had the same problem yesterday while trying to set it up. Solution is pretty simple, you just have to set scala somewhere in project settings.
You are mixing code compiled with two different Scala versions.
I use Netbeans to write scala programs. So far it works very well with my codes. You can try the plugin here: http://wiki.netbeans.org/Scala68v1.
I was getting this error and also had to right click on the project and "Open Module Settings". However, it was more than just hitting apply. I had to make sure that my Content Root was correct for each project. For some reason, there were some incorrect Source and Test Folders.
My project uses maven as the main build tool and importing the project into Intellij is probably what created these incorrect settings.
I had similar problem, following this blog post instructions solved the problem for me