Get project in Eclipse plugin without having an open editor - eclipse-plugin

Question

In a Eclipse plugin it's easy to get the current project(IProject) if there's an editor opened, you just need to use this snippet:
IEditorPart editor = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage().getActiveEditor();
IFileEditorInput input = (IFileEditorInput)editor.getEditorInput();
IFile file = input.getFile();
IProject project = file.getProject();
But, is there a way to get the project if I don't have any kind of file opened in the editor?, i.e: imagine that you have a plugin that adds an option when you right click a project, and if you click this option a dialog window is launched, how can I print the project name in this dialog?

Answer 1

For menu items and the like which use a 'command' with a 'handler' you can use code in the handler which is something like:
public class CommandHandler extends AbstractHandler
{
#Override
public Object execute(ExecutionEvent event) throws ExecutionException
{
ISelection sel = HandlerUtil.getCurrentSelection(event);
if (sel instanceof IStructuredSelection)
{
Object selected = ((IStructuredSelection)sel).getFirstElement();
IResource resource = (IResource)Platform.getAdapterManager().getAdapter(selected, IResource.class);
if (resource != null)
{
IProject project = resource.getProject();
...
}
}
return null;
}
}

Answer 2

What do you mean by "The current project"? Getting a specific project will always require some way of uniquely identifying that specific project.
If by current project you mean that the project is open, then that's not a good criterion for uniqueness (in the general case), since multiple projects can be open at the same time.
A guarantee of uniquely defining a project is by getting a reference to a resource contained by that project. For example, this can be done through the editor input, as you state, or trough a selection, as greg pointed out.
If you have the project's name, then you can use IWorkspaceRoot#getProject(String), but I assume that's not the case. Still, for completeness:
ResourcesPlugin.getWorkspace().getRoot().getProject("MyProject");
You could also get a list of all projects, and iterate over that list to check for a property that you know the project has (or the projects have). See the example below. Of course, this again doesn't guarantee uniqueness in the general case, since there can be multiple projects that satisfy the criteria. That's why I used Lists in the example.
IProject[] projects = ResourcesPlugin.getWorkspace().getRoot().getProjects();
List<IProject> openProjects = new ArrayList<>();
List<IProject> myNatureProjects = new ArrayList<>();
for(IProject project : projects)
{
if(project.isOpen())
openProjects.add(project);
if(project.hasNature("MyNatureId")
myNatureProjects.add(project);
}