OpenTargetAction.java

package net.sourceforge.c4jplugin.internal.ui.actions;

import net.sourceforge.c4jplugin.C4JActivator;
import net.sourceforge.c4jplugin.internal.core.ContractReferenceModel;
import net.sourceforge.c4jplugin.internal.util.SelectionConverter;

import org.eclipse.core.resources.IResource;
import org.eclipse.jdt.core.ICompilationUnit;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IMethod;
import org.eclipse.jdt.core.JavaCore;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jdt.ui.JavaUI;
import org.eclipse.jface.action.IAction;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.ui.IEditorActionDelegate;
import org.eclipse.ui.IEditorInput;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.IObjectActionDelegate;
import org.eclipse.ui.IWorkbenchPart;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.PlatformUI;

public class OpenTargetAction implements IObjectActionDelegate {

	public void run(IAction action) {
		IEditorInput editorInput = null;
		try {
			editorInput = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage().getActiveEditor().getEditorInput();
		}
		catch (NullPointerException e) { 
			return; 
		}
		
		IResource resource = JavaUI.getEditorInputJavaElement(editorInput).getResource();
		IResource target = ContractReferenceModel.getTarget(resource);
		
		if (target == null) return;
		
		IJavaElement element = JavaCore.create(target);
		try {
			JavaUI.openInEditor(element);
		} catch (PartInitException e) {
			C4JActivator.log(e);
		} catch (JavaModelException e) {
			C4JActivator.log(e);
		}
	}

	public void selectionChanged(IAction action, ISelection selection) {
		
	}

	public void setActivePart(IAction action, IWorkbenchPart targetPart) {
		if (targetPart == null) return;
		
		IStructuredSelection selection;
		try {
			selection = SelectionConverter.getStructuredSelection(targetPart);
		} catch (JavaModelException e) {
			e.printStackTrace();
			action.setEnabled(false);
			return;
		}
		
		if (selection.isEmpty()) {
			action.setEnabled(false);
			return;
		}
		
		Object sel = selection.getFirstElement();
		
		if ((sel instanceof IMethod &&
			ContractReferenceModel.isContracted(((IMethod)sel).getCompilationUnit().getResource()))
			|| (sel instanceof ICompilationUnit &&
					ContractReferenceModel.isContracted(((ICompilationUnit)sel).getResource()))) {
				action.setEnabled(true);
		}
		else {
			action.setEnabled(false);
		}
	}

}