I have just upgraded my SpringSource Tools Suite (STS, a variant IDE of Eclipse) to the latest version (v3.6.1). Then all my JUnit unit tests can not be run again. I am getting this error:
Class not found ClassToTest
java.lang.ClassNotFoundException: ClassToTest
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
According to this blog:
ClassNotFoundException when running JUnit unit tests within Eclipse (using Maven),
it is because of some misconfiguration of Maven plugin in Eclipse. However, in STS 3.6.2 I cannot find this option "Include Modules" in the Maven plugin. How can I fix this problem and re-enable my unit tests?
There are still some back-draws on the current m2e plugin. Unit-test-cases couldn't be run as their including project grouped in a working-set. Following may help:
Right click on project including junit-tests.
Select Maven -> Disable Workspace Resolution
Try then to run your test again.
OK it seems I'll have to answer this question by myself.
The main reason for this problem is still the m2eclipse eclipse plug-in. The new version of this plugin does not support nested modules in one project. If we really need to see multiple modules we have to remove the old one from the package explorer and create a working set and import the project again using the option "import existing maven projects". The eclipse import wizard will pop up a window and ask you which module to be imported. Then we can select all the modules and finish the import. As a result the working set will contain all the modules of your project and treat each module as a separate project, although in the workspace your modules are still in one project. By doing this it resolves all the problems that I have come across in Eclipse related to classpath, such as not being able to search a class or not being able to run the unit tests and get a java.lang.ClassNotFoundException.
For reference, here is an article to teach you how to create a working set:
Working set
I think you can import the project without creating a new working set but the working set will keep all the modules that belong to your project in one set so it is easier to organize.
I wish I had the answer two months ago so I wouldn't have spent much time searching for a solution.
I think I have found the solution, at least this worked for me:
right click on the project and choose 'Maven' -> 'Update Dependencies'
Then when I tried , I did not get ClassNotFoundException .
I tried everything mentioned here and in other posts. Some of the solutions that people proffered were:
Change the output folder for the test classes.
Create a custom builder for the project that would run test-compile from Maven.
Move the Maven dependencies higher in the Order and Export list in the project build path.
There were many, many more but the one that I found to work was as follows:
Close the development environment.
Delete the jars used by the project from my local Maven repository.
Open the IDE.
Build the project.
Run the test.
After hours of beating my head against my keyboard and following suggested solutions, this one worked!
We too faced the same ClassNotFoundException while trying to run JUnit test class. But when we tried using the following steps, it successfully started running.
Select your project.
Click on the project option displayed in toolbar in the eclipse IDE.
Select “clean”.
Now try running the test file.
As a work-around, try running mvn test-compile (either in Eclipse or from the command line), then try running the Junit test within Eclipse.
Related
I don't understand exactly what is the way of working with maven projects in Eclipse.
The problems I have are often with projects I download from github. If I set the project myself it usually work, so I think I'm doing something different from the majority of people.
I'll try to detail a specific case:
I clone a repo, let's say: https://github.com/spring-guides/tut-spring-boot-oauth2
In Eclipse I import "existing maven project"
The project has a "Maven nature" as indicated by M on the folder icon
I try to run java class with main from Eclipse. First strange thins is that the "Run As" menu doesn't have "Run as a Java application"
I have to configure the configuration manually. Now it runs, but strange things happens, like I can't edit the file as the "content assist" throw errors instead of giving the normal assists.
I notice that the project has no "source folder". So my first instinct is to add a Java nature or select src as source folder
So I add Java nature to the project. This is a disaster. It can compile anymore as it can find packages. All classes have errors. I try to play around setting source folders on /src or /src/main/java. Sometimes I fix the errors but I can't run (and now I have run as Java application) but when I run it can't load the class
So in the end, I'm a bit confused and I don't know if I explained clearly what I'm doing.
I think I would like to know in a simple way how people are doing it, rather than trying to correct my steps as I'm probably creating a mess myself.
Any help or suggestion welcome.
I'm using the last version of eclipse. I don't know which other tool's versions are relevant.
P.S. I also refresh,restart,clean rebuild the project often after touching things...but it doesn't get better
Maven is a build (management) tool. Simply spoken, its task is to create a JAR that can be used as a dependency/library by other projects or when running java -jar ....
Running a project's code isn't part of it (apart from unit and integration tests code and by using non-default plugins for special situations). Running code is part of Eclipse (or any other IDE) with its Run Configurations.
If I create a test class I can't run it from eclipse until I have run it via maven on the command line first. My project build path output folder is pointing to project/target/classes. And build automatically is checked in the eclipse.
Anyone know why eclipse doesn't create the classes automatically?
Here's how the layout and build path of your project should look like.
Layout
Build path
In addition to what Marcel said, someone who runs into the same problem should look for dependencies between projects within Eclipse.
I was working with project A, which depended on project B. Project A was built and run normally, except for the problem mentioned in this post (run a JUnit class test). After digging for a while, I noticed that Project B had a build error (a source folder went missing, who knows why) and Eclipse was not building the project B, which caused an error on project A.
As soon as I fixed the project B build error, the problem with JUnit class was solved.
Background
I'm currently trying to extend Junit (org.eclipse.jdt) in order to do some tracing.
Therefore I created my own plugin project which (among others) provides a class which should be used by the junit runtime plugin.
I have setup my project as a dependency for junit and the package containing my class is listed as "exported" in my Manifest in the runtime tab. If I run the plugins as an eclipse application everything builds and starts allright and.
Problem
However, if in the started eclipse I perform a "Run as Junit", I get a NoClassDefFoundError concerning my class. In my understanding this means, that at runtime my class is not visible in the started eclipse. I thus printed the classpath while running and like expected my plugin doesn't show up.
Do I have to add my plugin to the "runtime" settings of the junit plugin? In the Manifest, my package is not available under the "export -> add" button. I tried importing a jar of my plugin and configuring those exports manually here, but this did not help either.
My thought process kind of gets stuck with this "run in run" configuration...
Any help is welcome!
Digging deeper in the code I found that the reason for the error is, that the part which calls my code and throws the error is run in a seperately started VM which has its classpath set via code. Nothing was wrong with the configuration, it just was not used in this case.
So if you ever stumble upon a "VMRunnerConfiguration" while having classpath problems, this might be your problem. ;)
Problem: I cannot setup Run Configurations to run scalatest for the Scalatests in my project.
Steps to reproduce:
Right click on Scala Suite and click on Run as -> Run configurations..
On the left, I see a configuration template for ScalaTest. I click on New and fill the Name but it cannot find the suite-class.
Note: It is mentioned here that I should see Run as -> ScalaTest - Suite but I do not see that option. I tried using context menu in the editor, and in the package explorer
Steps taken:
Using: Scala IDE for Eclipse version: 2.1.0.m3-2_09
Using SBT, assemble project, run eclipse command and then import project and dependencies into Eclipse
Project compiles. ScalaTest code compiles(scalatest_2.9.2-1.8.jar is in the 'Referenced Libraries' configuration)
I've been fighting a similar problem for the past few days; Lily / Jimbo's answer didn't quite match my situation, but helped me find the right direction.
In my case, I was using a third-party library that I'd copied in. The package names of the classes and tests matched, but the folder structure did not -- all of my tests were directly in Play's "/test" folder, rather than in folders that matched the package names. This didn't show any errors, but was broken: packages ought to match folders. When I built the right folder structure underneath test, and recompiled, the expected "Run As -> ScalaTest - Suite" options showed up.
Don't know if your problem is the same, but you might check this if you haven't already found the issue...
This could be caused by a misalignment between the scalatest and the scala eclipse IDE version. Try scalatest_2.9.0-2.0.M5b.jar or scalatest_2.10-2.0.M5b.jar. The former jar definitely works with ide 2.0.9.x so maybe the new version needs the 2.10 jar. Pick your version carefully from here
Willem's answer is what worked for me. Getting both plugins from the same update site (from the list on Scalatest's github site), seemed to work for me using Kepler.
for my case, one click on 'Reimport All Maven Projects' icon, like 'Refresh' icon, solved the problem.
Not sure if you fixed the error, but I had similar a error yesterday and was pulling my hair trying to fix it (none of the suggestions I found by googling seemed to help me). So for me, it turns out that it's as easy as package hierarchy in my test suite.
I am using the play framework, so naturally my folders look like this controllers.package1.package2.... and this applies to my test folders also.
Now my test classes however, have the package definition package1.package2..... (no "controllers" as prefix).
If I run the tests on sbt/play command prompt, it's not a problem. But running them through Eclipse would give me the problem you described.
So anyways... thought I'd share this, in case this could help.
it's a bit annoying combined with the view template compile issue in play framework. but my approach is to regenerate the eclipse project file and add view template path into the class path
I would just like to setup a new GWT project in Eclipse and use Maven for dealing with all the jar jungle. I used gwt-maven-plugin with this instructions, but I can't get the project to work in Eclipse.
What I've actually done:
Created a maven project using the archetype gwt in command line.
Imported the projet in eclipse using import > existing maven project
While doing that I had errors saying:
gwt-maven-plugin:2.3.0-1:generateAsync - "No marketplace entries found to handle"
gwt-maven-plugin:2.3.0-1:i18n - "No marketplace entries found to handle"
gwt-maven-plugin:2.3.0-1:exploded - "No marketplace entries found to handle"
These errors don't go away even if I ignore them on the import.
How can I make these projects working? Is the problem that I skipped the "process-resources" setting? (There is no such setting in the latest version of m2e.)
Should I even use gwt-maven-plugin? Is there any other way of making a GWT project to use Maven? Or – is there any other way to fight with the jar jungle? What does GWT guys use?
I use Eclipse Indigo with m2e plugin 1.0.0 and Google suite plugin version 2.3.3.
Eventually I gave up Maven. As one other developer said "good ideas and bad code build communities faster" , I also remember my experience with Maven on all the projects: very promising on the beginning, but eventually you get to some problems and end up working more with configuring Maven than actually dealing with your own code.
I decided to manually copy needed .jar-s into /lib folder. I spent some time due to transitive dependencies, but LESS than dealing with Maven and now I have things under control. If sometime in the future working with libraries will become an overhead, I will consider using Ivy.
If someone wishes to stick with Maven, I lately found a very useful link by Google team:
http://code.google.com/p/google-web-toolkit/wiki/WorkingWithMaven
They recommend using their sample projects and not gwt-maven-plugin archetypes (due to issues). I agree. They also provide needed pom lifecycle changes for Eclipse Indigo.
According to a recent post on the gwt-maven-plugin mailing list the Maven integration is not complete for Eclipse Indigo, since the M2Eclipse 1.0 release has brought about a large number of changes. The suggested workarounds from David Chandler, Google engineer, are:
You can run "mvn package" on the command line or right-click on the project > Maven > Run as > Maven build.
The plugin execution failures you're seeing can be resolved by adding lifecycle mapping metadata as in the sample POMs. They are only needed for Indigo. You should not get these errors in Helios or when running mvn package from the command line.
Disclaimer: The following guidelines are for Windows users. These steps are on the basis that, they have worked when tried by the replier and doesn't guarantee fulfledge working unless experimented by self and tried with proper prerequisites.
::Creating a simple gwt project using archetype::
Following are few commands that can be used to create a simple gwt project "Web Starter Application":
mvn archetype:generate -DarchetypeGroupId=org.codehaus.mojo
-DarchetypeArtifactId=gwt-maven-plugin -DarchetypeVersion=2.3.0
mvn -DarchetypeGroupId=org.codehaus.mojo
-DarchetypeArtifactId=gwt-maven-plugin -DarchetypeVersion=2.3.0 -DgroupId={project packaging} -DartifactId={application name} -Dversion=1.0 org.apache.maven.plugins:maven-archetype-plugin:generate
mvn -DarchetypeGroupId=org.codehaus.mojo
-DarchetypeArtifactId=gwt-maven-plugin -DarchetypeVersion=2.3.0 -DgroupId={project packaging} -DartifactId={application name} -Dversion=1.0 -Dmodule={module name} org.apache.maven.plugins:maven-archetype-plugin:generate
(The value of archetypeVersion can be 2.3.0 or any higher stable version.)
Few coordinates are required by maven to create the gwt project. They are as follows:
groupId
artifactId
version
module
The first command doesn't take any of the above coordinates hence, we need to supply them at the time it executes. Notice that the archetype goal is mentioned right at the beginning of the command. It is mandatory to give the archetype goal.
The meanings of these coordinates can be found here.
One of the best ways to start with understanding maven is this.
The second command doesn't consider the module name hence, you will be prompted to give it at the time the command executes.
The third command is equivalent to running it in batch mode where you just have to confirm the inputs for groupId, artifactId, version, module as mentioned in command itself.
Once any of these commands gives a BUILD SUCCESS result, then navigate to the just-now-created project folder from command line and execute the following command:
mvn gwt:run
It should start the project in Development Mode so that you can Launch the Default Browser to run the project or Copy the URL to clipboard and navigate to it through any browser.
Good luck with the execution.