I have the following code in a file in eclipse Philsophers.scala in an eclipse project.
http://www.jakubkorab.net/wp-content/uploads/2011/01/Philosophers.scala
When I right click to run, eclipse does not recognize the runner in this class. Any ideas?
Assuming that it's currently in the default package: it will run once you put it in a correct package, because the file itself specifies a package. The easiest thing is to remove:
package net.jakubkorab.philosophers
Related
I have installed the m2 plugin for eclipse, but i no longer can create packages, i have to create folders. This way one cannot create a java class directly, but have to create a text file with .java extension. All the nice things, like eclipse writing down the package name of the class and the imports, are gone!
Besides, whenever i try to autocomplete method names or code, all i get is a nasty warning: "This compilation unit is not on the build path of a java project". So all the ide functionalities are gone! eclipse becomes just a variation of notepad.
thanks
After i restarted my machine the issue got solved.
I've created a Play Framework program via Typesafe Activator (so it follows the template exactly).
I used sbteclipse-plugin version 3.0.0 to create an Eclipse project and imported that into Scala IDE 4.0.0. These are all the latest versions at the time of writing.
The Scala IDE definitely seems to support the Play Framework. It has syntax highlighting for the custom formats, including the routing file and templates. Yet, it doesn't seem to be able to find the views from the controllers. In particular, the call to views.html.index triggers an error: "object index is not a member of package views.html".
I tried enabling refreshing using native hooks or pooling as detailed here, but it had no affect.
I should note that while the code has been compiled in the command line (with activator ~run), it hasn't been compiled in Scala IDE, since I don't know how to (it doesn't seem to be documented anywhere).
What can I do to get rid of these false errors?
EDIT: After running activator clean ~run, I have another error: The project cannot be built until build path errors are resolved. There's no further details on what these build path errors are.
Update: Just upgrade to sbteclipse version 5.1.0 and everything should work out of the box. Also make sure you follow the Play documentation on how to set up Eclipse/ScalaIDE.
This is a known bug in sbteclipse, which probably will be fixed soon.
For now, you can add the following line to your build.sbt:
EclipseKeys.createSrc := EclipseCreateSrc.All
Kill the SBT console and run sbt eclipse again. That should add the following line to the .classpath file within your project folder as a workaround:
<classpathentry kind="src" path="target/scala-2.11/twirl/main"/>
Refresh your Eclipse project to pick up the change.
I had the same issue, also with Scala IDE 4.0.0 . I followed mkurz instuctions and they worked like a charm. But instead of changing the .classpath file in the project folder manually I used Eclipse interface:
In the top menu of the main window, click on Project and then on Properties.
In the Properties window, click on Java Build Path option (options list is on the left)
In the Source tab, click on Add Folder... button.
In the Source Folder Selection window, choose the target/scala-2.11/twirl/main folder, so it is included in the compilation path. Click Ok button.
Click Ok in the Properties window.
Now the project should compile just fine :) . With that I was able to finish the play setup example in Scala IDE website
I tried #mkurz solution first, but also ran into the same error as #matt. I became frustrated that I could not generate the eclipse project without having to go to the Eclipse project properties to manually fix the build errors. After some investigation, I discovered the solution that removed all errors entirely. Add this your build.sbt:
unmanagedSourceDirectories in Compile <+= twirlCompileTemplates.target
Or if that does not work for you, you could also use:
unmanagedSourceDirectories in Compile <+= target.zipWith(scalaBinaryVersion) { (b,v) => b / s"scala-$v/twirl/main" }
Good bye, build errors!
I got the same error message.
Are you using java8 as jre in eclipse?
After switching back from java8 to java7, everything worked fine again.
If, after following Mkurz' instructions (adding EclipseKeys.CreateSrc... ), your problems are not solved, click on Project -> Properties -> Java Build Path. Look at the source folders tab.
You may find a duplicate file folder named .../src_managed/main (Thanks Matt). If so, close the project. Remove ONE of the two ../src_managed/main entries from the .classpath file (located in the base of the activator/SBT project directory). Reopen and clean the project and you should be good to go.
For me, it turned out that installed JRE in the Scala IDE was openjdk, changed it to Oracle Java 8 and it worked.
So I created a project in netbeans and then added a new JFrame form (this is my first gui app). I was wondering if there was any way to open the source code in another app like textedit and compile it using terminal (javac blah.java, java blah).
I managed to create a .jar file (clean and build) and it works perfectly fine when I try to run it (double click). Now I managed to find the .java file in src but when I compile it I receive 36 errors, which makes no sense since it built and ran perfectly fine and the jar file works.
Essentially I want to just take the source code (not the entire project) and compile it, for example on a computer that does not have netbeans using terminal. Can this be done?
I would also like to emphasize that I'm just a beginner. Thanks!
Standard NetBeans projects are based on Apache Ant. So it should be sufficient to install Ant and a JDK to compile/package your project on another computer or CI system.
What i found to be the culprit to this problem is that on your source code make sure it does not have package. So for example:
"package blablah"
All you have to do is get rid of that, and then take your java file and it should compile perfectly. For some reason that causes the nodefclass error.
I have an eclipse plugin project com.prosseek.asttest, and I spin off a new plugin project com.prosseek.impactAnalyzer that has one class CallHierarchyGenerator.java. Now asttest project depends on impactAnalyzer project. I had no choice but to make impactAnalyzer project eclipse plugin as it uses JDT library.
After setting up the build path in com.prosseek.asttest, it builds without a problem.
However, when I execute the plugin, I got an error missing CallHierarchyGenerator.java class.
What might be wrong?
If you are running this as an OSGI or Eclipse Application, you need to explicity export packages as available to other plugins as by default they are not. Open your manifest editor in plugin 1. Click on the runtime tab and add the packages as "Exported" then the class loader in blugin 2 will be able to find it.
Also looks like you might be doing the class path configuration wrong. in plugin 2 make sure you add plugin 1 as a dependency in the dependencies tab of the manifest editor. Looks like you are doing a dependency configuration as if it were a regular java application
Based on Duncan's answer, I could fix this issue.
Export packages in impactAnalyzer
Actually I didn't add it manually, but it's already exported, as (I guess) I did it with Quick Assist automatically.
Required Plug-ins
I had to Add com.prosseek.impactAnalyzer in the dependecies.
Run configuration update
I had one more step to do, I had to open run configuration to add required plug-ins.
Export the plugin
When exporting the asttest plugin, I also had to export impactAnalyzer also.
After cloning playframework from github and importing java sources into eclipse there are a lot of build errors shown.
Running the goals from ant file in eclipse works fine as well as building from cli directly.
How can i resolve these errors in eclipse?
I took the following steps to import play into eclipse:
new -> other -> Java>New Java Project from Existing Ant Buildfile
select play/framework/build.xml
checking the 'Link to the build file in the file system' checkbox
Finish
The errors result from differences between eclipse internal build path
and classpath available for ant at runtime.
First Eclipse only imports rt.jar from system path. This may lead to
missing dependecies in javax.net packages (e.g.
javax.net.ssl.SSLException), which is located in jsse.jar. To fix, right
click on project->Properties->Java Build Path->Libraries->Add Library->
JRE System Library.
Second, play has dependencies to classes from ant runtime. To fix, right
click on project->Properties->Java Build Path->Libraries->Add
Library->User Library
There you have to add a new User Library (perhaps call it ANT) and add
all ant-jars from your ant installation (/usr/share/ant/lib/ worked for
me). Then add this user library to play projects build path.
From the Oliver's answer, I had also to add the jce.jar lib in my classpath.
It comes from the $JDK/jre/lib directory.