How does JUnit find the eclipse plug-in being tested? - junit

Question

I am writing a plug-in (ClassRefactoringPlugin) that examines source code in Eclipse 3.6.1. The plug-in contains a CallData class that examines a Java source file and figures out which Java elements are called from a method using JDT operations. I wrote a JUnit 4 test for this class that also resides in the ClassRefactoringPlugin project. When I ran it as a JUnit plug-in test, I got:
Java Model Exception: Java Model Status [ClassRefactoringPlugin does not exist]
What have I done wrong? The configuration specifies to launch with all workspace and enabled target plug-ins, and ClassRefactoringPlugin is in my dropins directory. (Although shouldn't the project's version of the plug-in be recognized by the spawned workspace?)
Here's the stack trace:
!MESSAGE CallData.calculateCalledMethods: Java Model Exception: Java Model Status [ClassRefactoringPlugin does not exist]
Java Model Exception: Java Model Status [ClassRefactoringPlugin does not exist]
at org.eclipse.jdt.internal.core.JavaElement.newJavaModelException(JavaElement.java:502)
at org.eclipse.jdt.internal.core.Openable.generateInfos(Openable.java:246)
at org.eclipse.jdt.internal.core.Openable.openAncestors(Openable.java:504)
at org.eclipse.jdt.internal.core.Openable.generateInfos(Openable.java:240)
at org.eclipse.jdt.internal.core.Openable.openAncestors(Openable.java:504)
at org.eclipse.jdt.internal.core.Openable.generateInfos(Openable.java:240)
at org.eclipse.jdt.internal.core.Openable.openAncestors(Openable.java:504)
at org.eclipse.jdt.internal.core.CompilationUnit.openAncestors(CompilationUnit.java:1170)
at org.eclipse.jdt.internal.core.Openable.generateInfos(Openable.java:240)
at org.eclipse.jdt.internal.core.SourceRefElement.generateInfos(SourceRefElement.java:107)
at org.eclipse.jdt.internal.core.JavaElement.openWhenClosed(JavaElement.java:515)
at org.eclipse.jdt.internal.core.JavaElement.getElementInfo(JavaElement.java:252)
at org.eclipse.jdt.internal.core.JavaElement.getElementInfo(JavaElement.java:238)
at org.eclipse.jdt.internal.core.JavaElement.getChildren(JavaElement.java:193)
at org.eclipse.jdt.internal.core.JavaElement.getChildrenOfType(JavaElement.java:207)
at org.eclipse.jdt.internal.core.SourceType.getMethods(SourceType.java:403)
at nz.ac.vuw.ecs.kcassell.utils.EclipseSearchUtils.addDesiredMethods(EclipseSearchUtils.java:333)
at nz.ac.vuw.ecs.kcassell.utils.EclipseSearchUtils.getMethods(EclipseSearchUtils.java:210)
at nz.ac.vuw.ecs.kcassell.callgraph.CallData.collectMethodCallData(CallData.java:203)
at nz.ac.vuw.ecs.kcassell.callgraph.CallData.calculateCalledMethods(CallData.java:176)
at nz.ac.vuw.ecs.kcassell.callgraph.CallData.collectCallData(CallData.java:151)
at nz.ac.vuw.ecs.kcassell.callgraph.CallDataTest.testCollectCallData(CallDataTest.java:67)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at junit.framework.TestCase.runTest(TestCase.java:168)
at junit.framework.TestCase.runBare(TestCase.java:134)
at junit.framework.TestResult$1.protect(TestResult.java:110)
at junit.framework.TestResult.runProtected(TestResult.java:128)
at junit.framework.TestResult.run(TestResult.java:113)
at junit.framework.TestCase.run(TestCase.java:124)
at junit.framework.TestSuite.runTest(TestSuite.java:232)
at junit.framework.TestSuite.run(TestSuite.java:227)
at org.junit.internal.runners.JUnit38ClassRunner.run(JUnit38ClassRunner.java:83)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:49)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.pde.internal.junit.runtime.RemotePluginTestRunner.main(RemotePluginTestRunner.java:62)
at org.eclipse.pde.internal.junit.runtime.UITestApplication$1.run(UITestApplication.java:116)
at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:134)
at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3515)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3164)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2640)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2604)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2438)
at org.eclipse.ui.internal.Workbench$7.run(Workbench.java:671)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:664)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:115)
at org.eclipse.pde.internal.junit.runtime.UITestApplication.start(UITestApplication.java:47)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:369)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:619)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:574)
at org.eclipse.equinox.launcher.Main.run(Main.java:1407)
at org.eclipse.equinox.launcher.Main.main(Main.java:1383)
I am wondering if the error message might be a red herring. The error occurs when making a call to
IMethod[] methods = type.getMethods();
If I set a breakpoint there and look at type in the Variables view of the debugger, I see:
CallDataTest (not open) [in CallDataTest.java [in nz.ac.vuw.ecs.kcassell.callgraph [in test [in ClassRefactoringPlugin]]]]
I wonder if I am omitting some important preliminary step to make the project available for examination. First, I attempt to activate the workbench, like so:
public static void activateWorkbench() {
// possible for PlatformUI.getWorkbench to throw an IllegalStateException
// if the workbench is not yet started e.g createAndRunWorkbench() has not yet been called
IWorkbench workbench = PlatformUI.getWorkbench();
IWorkbenchWindow workbenchWindow =
workbench.getActiveWorkbenchWindow();
workbenchWindow.getActivePage();
}
Then I try to get type using its handle:
protected IType iType = EclipseUtils.getTypeFromHandle(
"=ClassRefactoringPlugin/test<nz.ac.vuw.ecs.kcassell.callgraph{CallDataTest.java[CallDataTest");
public static IType getTypeFromHandle(String handle) {
IType type = null;
IJavaElement element = JavaCore.create(handle);
if (element == null) {
System.err.println(" No element created from " + handle);
} else if (element instanceof IType) {
type = (IType) element;
}
return type;
}
I am new to plug-in development, so any help would be much appreciated.
Cheers,
Keith

Answer 1

I am a little unsure exactly what you are trying to do here, but it looks like you are trying to write a JUnit test for your plugin. Is this right?
According to the java element handle identifier that you are creating, there should be a project called ClassRefactoringPlugin in your workspace and in there, is a source folder called test, and a java class called CallDataTest in a package called nz.ac.vuw.ecs.kcassell.callgraph.
I'm guessing that this is not the case and that you want to reference a class file in the plugin that you just created.
Before you can do any of that, you need to import a project into your test workspace, set its classpath, and then you can access its contents using handle identifiers.
I may be misunderstanding what you are trying to do, but it does seem like you are trying to access a java file that doesn't exist in your workspace. If you can confirm that this is what you want to do, I can point you to some test code that does exactly what you want.
There are some open source projects that do exactly this and you can borrow some of their source code for your purpose. A project that I am familiar with is Groovy-Eclipse http://groovy.codehaus.org/Eclipse+Plugin (since I am the lead on that project).
Here is a link to the class that we use to create and manage test projects:
https://svn.codehaus.org/groovy/eclipse/trunk/ide-test/org.codehaus.groovy.eclipse.tests/src/org/codehaus/groovy/eclipse/test/TestProject.java
You can use some or all of this code for your own tests. Just remember to delete all projects at the end of each test.

Answer 2

Had a similar error for different reasons. My error started after renaming the target package in the project. After I tried the solution from paskster without success, I started diggin'.
The actual problem was that renaming the package name from the manifest file didn't work as expected. I thought it would change everything everywhere. However, the old package name was still in the manifest file in the test directory, and in some views in the resources. After renaming those manually and rebuilding the project, the error was gone.
This is the accepted answer for another question:
Java Model Exception: Java Model Status [gen [in MyApp] does not exist] after Eclipse Android project Clean
Since the owner of this question up-voted this answer as a solution with a link to this question, I thought I'd post it here as well.