Failed to create project test1

[elharo]

At head while trying to create standard project

Java Model Exception: Java Model Status [test1 does not exist]
	at org.eclipse.jdt.internal.core.JavaElement.newNotPresentException(JavaElement.java:556)
	at org.eclipse.jdt.internal.core.JavaModelManager.getPerProjectInfoCheckExistence(JavaModelManager.java:2307)
	at org.eclipse.jdt.internal.core.JavaProject.getPerProjectInfo(JavaProject.java:1909)
	at org.eclipse.jdt.internal.core.JavaProject.getRawClasspath(JavaProject.java:1931)
	at com.google.cloud.tools.eclipse.appengine.newproject.CreateAppEngineWtpProject.addJunit4ToClasspath(CreateAppEngineWtpProject.java:121)
	at com.google.cloud.tools.eclipse.appengine.newproject.CreateAppEngineWtpProject.execute(CreateAppEngineWtpProject.java:108)
	at org.eclipse.ui.actions.WorkspaceModifyOperation$1.run(WorkspaceModifyOperation.java:108)
	at org.eclipse.core.internal.resources.Workspace.run(Workspace.java:2241)
	at org.eclipse.ui.actions.WorkspaceModifyOperation.run(WorkspaceModifyOperation.java:130)
	at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:119)

[elharo]

I have not been immediately able to reproduce this. Perhaps a thread issue?

  private static void addJunit4ToClasspath(IProgressMonitor monitor, IProject newProject)
      throws CoreException {
    IJavaProject javaProject = JavaCore.create(newProject);
    IClasspathAttribute nonDependencyAttribute =
        UpdateClasspathAttributeUtil.createNonDependencyAttribute();
    IClasspathEntry junit4Container = JavaCore.newContainerEntry(
        JUnitCore.JUNIT4_CONTAINER_PATH,
        new IAccessRule[0],
        new IClasspathAttribute[] {nonDependencyAttribute},
        false);
    IClasspathEntry[] rawClasspath = javaProject.getRawClasspath();
    IClasspathEntry[] newRawClasspath = Arrays.copyOf(rawClasspath, rawClasspath.length + 1);
    newRawClasspath[newRawClasspath.length - 1] = junit4Container;
    javaProject.setRawClasspath(newRawClasspath, monitor);
  }

The line that fails is javaProject.getRawClasspath() so if JavaCore.create(newProject) has not yet finished we could see this.

[elharo]

This is the code that threw the exception. The problem is not that the project doesn't exist but that it doesn't have the Java nature:

	public PerProjectInfo getPerProjectInfoCheckExistence(IProject project) throws JavaModelException {
		JavaModelManager.PerProjectInfo info = getPerProjectInfo(project, false /* don't create info */);
		if (info == null) {
			if (!JavaProject.hasJavaNature(project)) {
				throw ((JavaProject)JavaCore.create(project)).newNotPresentException();
			}
			info = getPerProjectInfo(project, true /* create info */);
		}
		return info;
	}

[elharo]

It appears that in this case the project files weren't created before the exception was thrown. I don't immediately see what in this path could be asynchronous, but if it is then we could get to addJunit4ToClasspath before the project has been created and see these symptoms.

    CreateProjectOperation operation = new CreateProjectOperation(description, operationLabel); 
    try {
      operation.execute(subMonitor.newChild(10), uiInfoAdapter);
      mostImportant = createProjectFiles(newProject, config, subMonitor.newChild(80));
    } catch (ExecutionException ex) {
      throw new InvocationTargetException(ex);
    }

    addAppEngineFacet(newProject, subMonitor.newChild(4));

    BuildPath.addLibraries(newProject, config.getAppEngineLibraries(), subMonitor.newChild(2));

    addJunit4ToClasspath(subMonitor.newChild(2), newProject);

[elharo]

FYI, facets were not added to the project either.

[chanseokoh]

I can reliably reproduce this when I comment out a few things between operation.execute() and addJunit4ToClassPath():

    CreateProjectOperation operation = new CreateProjectOperation(description, operationLabel);
    try {
      operation.execute(subMonitor.newChild(10), uiInfoAdapter);
      //mostImportant = createProjectFiles(newProject, config, subMonitor.newChild(80));
    } catch (ExecutionException ex) {
      throw new InvocationTargetException(ex);
    }

    //addAppEngineFacet(newProject, subMonitor.newChild(4));

    //BuildPath.addLibraries(newProject, config.getAppEngineLibraries(), subMonitor.newChild(2));

    addJunit4ToClasspath(subMonitor.newChild(2), newProject);

[elharo]

Interesting. I don't see any reason that addJunit4ToClasspath should fail without those commented out lines (unless addAppEngineFacet also adds the Java nature?).

[chanseokoh]

Another possibility could be that things that we see are synchronous, while the completion of adding a Java nature is async.

[briandealwis]

I'm pretty sure IWorkspace.run() is synchronous. The java nature should be added by the addAppEngineFacets() with the Java facet, which I believe should be added synchronously too.

[briandealwis]

I wonder if the actual hookup in JDT is done via the auto builder... That's something odd I've seen recently in #1529.

[chanseokoh]

Explicitly setting the Java nature with description.setNatureIds(new String[]{JavaCore.NATURE_ID}); when creating a project (i.e., setting it before operation.execute()) eliminates the error in #1568 (comment).

    IProjectDescription description = workspace.newProjectDescription(name);
    description.setNatureIds(new String[]{JavaCore.NATURE_ID});  <------ HERE
    description.setLocationURI(location);

    String operationLabel = getDescription();
    SubMonitor subMonitor = SubMonitor.convert(monitor, operationLabel, 100);
    CreateProjectOperation operation = new CreateProjectOperation(description, operationLabel);
    try {
      operation.execute(subMonitor.newChild(10), uiInfoAdapter);
      //mostImportant = createProjectFiles(newProject, config, subMonitor.newChild(80));
    } catch (ExecutionException ex) {
      throw new InvocationTargetException(ex);
    }

    //addAppEngineFacet(newProject, subMonitor.newChild(4));

    //BuildPath.addLibraries(newProject, config.getAppEngineLibraries(), subMonitor.newChild(2));

    addJunit4ToClasspath(subMonitor.newChild(2), newProject);

It could be the case that addAppEngineFacet() adds the Java nature.

[chanseokoh]

The java nature should be added by the addAppEngineFacets() with the Java facet, which I believe should be added synchronously too.

So, I think it's not robust to rely on that addAppEngineFacets() will add the Java nature. If we don't call it, addJunit4ToClasspath() will fail. (Not to mention we are not 100% certain if it will add the nature synchronously). So I think it's best to explicitly set the nature when creating a project initially.

[chanseokoh]

FYI, facets were not added to the project either.

This concerns me a bit. @elharo If you still have the app that failed, can you check the content of the facet metadata conf file? If you did in a hosted Eclipse dev run, it should be at (if the app was named test1)

$HOME/runtime-gcloud-eclipse/test1/.settings/org.eclipse.wst.common.project.facet.core.xml

[elharo]

Good question. The only thing that was created was the .project file. Nothing else. That contains

<?xml version="1.0" encoding="UTF-8"?>
<projectDescription>
        <name>test1</name>
        <comment></comment>
        <projects>
        </projects>
        <buildSpec>
        </buildSpec>
        <natures>
        </natures>
</projectDescription>