core/plugins/org.eclipse.dltk.ui/src/org/eclipse/dltk/ui/infoviews/AbstractInfoView.java - dltk/org.eclipse.dltk.core - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2017 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *     xored software, Inc. - initial API and Implementation (Andrei Sobolev)
  *     xored software, Inc. - Patch 228846 (Alex Panchenko <alex@xored.com>)
  *******************************************************************************/
 package org.eclipse.dltk.ui.infoviews;

 import org.eclipse.core.runtime.IAdaptable;
 import org.eclipse.dltk.core.IModelElement;
 import org.eclipse.dltk.core.ModelException;
 import org.eclipse.dltk.internal.ui.editor.EditorUtility;
 import org.eclipse.dltk.internal.ui.text.ScriptWordFinder;
 import org.eclipse.dltk.internal.ui.util.SelectionUtil;
 import org.eclipse.dltk.ui.DLTKUIPlugin;
 import org.eclipse.dltk.ui.IContextMenuConstants;
 import org.eclipse.dltk.ui.ScriptElementLabels;
 import org.eclipse.dltk.ui.actions.SelectionDispatchAction;
 import org.eclipse.jface.action.IAction;
 import org.eclipse.jface.action.IMenuListener;
 import org.eclipse.jface.action.IMenuManager;
 import org.eclipse.jface.action.IToolBarManager;
 import org.eclipse.jface.action.MenuManager;
 import org.eclipse.jface.action.Separator;
 import org.eclipse.jface.resource.ColorRegistry;
 import org.eclipse.jface.resource.JFaceResources;
 import org.eclipse.jface.text.BadLocationException;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.IRegion;
 import org.eclipse.jface.text.ITextSelection;
 import org.eclipse.jface.util.IPropertyChangeListener;
 import org.eclipse.jface.util.PropertyChangeEvent;
 import org.eclipse.jface.viewers.ISelection;
 import org.eclipse.jface.viewers.ISelectionProvider;
 import org.eclipse.jface.viewers.IStructuredSelection;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.graphics.Color;
 import org.eclipse.swt.graphics.RGB;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.Display;
 import org.eclipse.swt.widgets.Menu;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.ui.IActionBars;
 import org.eclipse.ui.IEditorPart;
 import org.eclipse.ui.IPartListener2;
 import org.eclipse.ui.ISelectionListener;
 import org.eclipse.ui.IWorkbenchPart;
 import org.eclipse.ui.IWorkbenchPartReference;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.actions.ActionFactory;
 import org.eclipse.ui.contexts.IContextActivation;
 import org.eclipse.ui.contexts.IContextService;
 import org.eclipse.ui.part.ViewPart;
 import org.eclipse.ui.texteditor.ITextEditor;
 import org.eclipse.ui.texteditor.ITextEditorActionConstants;

 /**
  * Abstract class for views which show information for a given element.
  *
  */
 public abstract class AbstractInfoView extends ViewPart
 		implements ISelectionListener, IMenuListener, IPropertyChangeListener {

 	/**
 	 * @since 2.0
 	 */
 	protected static class KeywordInput {
 		private final String value;
 		private final IModelElement context;

 		public KeywordInput(String value, IModelElement context) {
 			this.value = value;
 			this.context = context;
 		}

 		public String getValue() {
 			return value;
 		}

 		public IModelElement getContext() {
 			return context;
 		}

 	}

 	/** ScriptElementLabels flags used for the title */
 	private final long TITLE_FLAGS = ScriptElementLabels.ALL_FULLY_QUALIFIED
 			| ScriptElementLabels.M_APP_RETURNTYPE
 			| ScriptElementLabels.F_APP_TYPE_SIGNATURE
 			| ScriptElementLabels.M_PARAMETER_TYPES
 			| ScriptElementLabels.M_PARAMETER_NAMES
 			| ScriptElementLabels.M_EXCEPTIONS
 			| ScriptElementLabels.F_PRE_TYPE_SIGNATURE
 			| ScriptElementLabels.M_PRE_TYPE_PARAMETERS
 			| ScriptElementLabels.T_TYPE_PARAMETERS
 			| ScriptElementLabels.USE_RESOLVED;
 	// private final long LOCAL_VARIABLE_TITLE_FLAGS = TITLE_FLAGS &
 	// ~ScriptElementLabels.F_FULLY_QUALIFIED |
 	// ScriptElementLabels.F_POST_QUALIFIED;
 	/** ScriptElementLabels flags used for the tool tip text */
 	private static final long TOOLTIP_LABEL_FLAGS = ScriptElementLabels.DEFAULT_QUALIFIED
 			| ScriptElementLabels.ROOT_POST_QUALIFIED
 			| ScriptElementLabels.APPEND_ROOT_PATH
 			| ScriptElementLabels.M_PARAMETER_TYPES
 			| ScriptElementLabels.M_PARAMETER_NAMES
 			| ScriptElementLabels.M_APP_RETURNTYPE
 			| ScriptElementLabels.M_EXCEPTIONS
 			| ScriptElementLabels.F_APP_TYPE_SIGNATURE
 			| ScriptElementLabels.M_APP_RETURNTYPE
 			| ScriptElementLabels.T_TYPE_PARAMETERS;
 	/*
 	 * @see IPartListener2
 	 */
 	private IPartListener2 fPartListener = new IPartListener2() {
 		@Override
 		public void partVisible(IWorkbenchPartReference ref) {
 			if (ref.getId().equals(getSite().getId())) {
 				IWorkbenchPart activePart = ref.getPage().getActivePart();
 				if (activePart != null)
 					selectionChanged(activePart, ref.getPage().getSelection());
 				startListeningForSelectionChanges();
 			}
 		}

 		@Override
 		public void partHidden(IWorkbenchPartReference ref) {
 			if (ref.getId().equals(getSite().getId()))
 				stopListeningForSelectionChanges();
 		}

 		@Override
 		public void partInputChanged(IWorkbenchPartReference ref) {
 			if (!ref.getId().equals(getSite().getId()))
 				computeAndSetInput(ref.getPart(false));
 		}

 		@Override
 		public void partActivated(IWorkbenchPartReference ref) {
 		}

 		@Override
 		public void partBroughtToTop(IWorkbenchPartReference ref) {
 		}

 		@Override
 		public void partClosed(IWorkbenchPartReference ref) {
 		}

 		@Override
 		public void partDeactivated(IWorkbenchPartReference ref) {
 		}

 		@Override
 		public void partOpened(IWorkbenchPartReference ref) {
 		}
 	};
 	/** The current input. */
 	protected Object fCurrentViewInput;
 	/** The copy to clipboard action. */
 	private SelectionDispatchAction fCopyToClipboardAction;
 	/** The goto input action. */
 	private GotoInputAction fGotoInputAction;
 	/** Counts the number of background computation requests. */
 	private volatile int fComputeCount;
 	private IContextActivation fContextActivation;
 	/**
 	 * Background color.
 	 *
 	 *
 	 */
 	private Color fBackgroundColor;
 	private RGB fBackgroundColorRGB;

 	/**
 	 * Set the input of this view.
 	 *
 	 * @param input
 	 *            the input object
 	 */
 	abstract protected void setInput(Object input);

 	/**
 	 * Computes the input for this view based on the given element.
 	 *
 	 * @param element
 	 *            the element from which to compute the input
 	 * @return the input or <code>null</code> if the input was not computed
 	 *         successfully
 	 */
 	abstract protected Object computeInput(Object element);

 	/**
 	 * Create the part control.
 	 *
 	 * @param parent
 	 *            the parent control
 	 * @see IWorkbenchPart#createPartControl(org.eclipse.swt.widgets.Composite)
 	 */
 	abstract protected void internalCreatePartControl(Composite parent);

 	/**
 	 * Set the view's foreground color.
 	 *
 	 * @param color
 	 *            the SWT color
 	 */
 	abstract protected void setForeground(Color color);

 	/**
 	 * Set the view's background color.
 	 *
 	 * @param color
 	 *            the SWT color
 	 */
 	abstract protected void setBackground(Color color);

 	/**
 	 * Returns the view's primary control.
 	 *
 	 * @return the primary control
 	 */
 	protected abstract Control getControl();

 	/**
 	 * Returns the context ID for the Help system
 	 *
 	 * @return the string used as ID for the Help context
 	 *
 	 */
 	abstract protected String getHelpContextId();

 	/*
 	 * @see IWorkbenchPart#createPartControl(org.eclipse.swt.widgets.Composite)
 	 */
 	@Override
 	public final void createPartControl(Composite parent) {
 		internalCreatePartControl(parent);
 		inititalizeColors();
 		getSite().getWorkbenchWindow().getPartService()
 				.addPartListener(fPartListener);
 		createActions();
 		createContextMenu();
 		fillActionBars(getViewSite().getActionBars());
 		IContextService ctxService = getSite()
 				.getService(IContextService.class);
 		if (ctxService != null) {
 			fContextActivation = ctxService
 					.activateContext(DLTKUIPlugin.CONTEXT_VIEWS);
 		}
 		PlatformUI.getWorkbench().getHelpSystem().setHelp(getControl(),
 				getHelpContextId());
 	}

 	/**
 	 * Creates the actions and action groups for this view.
 	 */
 	protected void createActions() {
 		fGotoInputAction = new GotoInputAction(this);
 		fGotoInputAction.setEnabled(false);
 		fCopyToClipboardAction = new CopyToClipboardAction(getViewSite());
 		ISelectionProvider provider = getSelectionProvider();
 		if (provider != null)
 			provider.addSelectionChangedListener(fCopyToClipboardAction);
 	}

 	/**
 	 * Creates the context menu for this view.
 	 */
 	protected void createContextMenu() {
 		MenuManager menuManager = new MenuManager("#PopupMenu"); //$NON-NLS-1$
 		menuManager.setRemoveAllWhenShown(true);
 		menuManager.addMenuListener(this);
 		Menu contextMenu = menuManager.createContextMenu(getControl());
 		getControl().setMenu(contextMenu);
 		getSite().registerContextMenu(menuManager, getSelectionProvider());
 	}

 	@Override
 	public void menuAboutToShow(IMenuManager menu) {
 		menu.add(new Separator(IContextMenuConstants.GROUP_OPEN));
 		menu.add(new Separator(ITextEditorActionConstants.GROUP_EDIT));
 		menu.add(new Separator(IContextMenuConstants.GROUP_ADDITIONS));
 		IAction action;
 		action = getCopyToClipboardAction();
 		if (action != null)
 			menu.appendToGroup(ITextEditorActionConstants.GROUP_EDIT, action);
 		action = getSelectAllAction();
 		if (action != null)
 			menu.appendToGroup(ITextEditorActionConstants.GROUP_EDIT, action);
 		menu.appendToGroup(IContextMenuConstants.GROUP_OPEN, fGotoInputAction);
 	}

 	protected IAction getSelectAllAction() {
 		return null;
 	}

 	protected IAction getCopyToClipboardAction() {
 		return fCopyToClipboardAction;
 	}

 	/**
 	 * Returns the input of this view.
 	 *
 	 * @return input the input object or <code>null</code> if not input is set
 	 */
 	protected Object getInput() {
 		return fCurrentViewInput;
 	}

 	// Helper method
 	ISelectionProvider getSelectionProvider() {
 		return getViewSite().getSelectionProvider();
 	}

 	/**
 	 * Fills the actions bars.
 	 * <p>
 	 * Subclasses may extend.
 	 *
 	 * @param actionBars
 	 *            the action bars
 	 */
 	protected void fillActionBars(IActionBars actionBars) {
 		IToolBarManager toolBar = actionBars.getToolBarManager();
 		fillToolBar(toolBar);
 		IAction action;
 		action = getCopyToClipboardAction();
 		if (action != null)
 			actionBars.setGlobalActionHandler(ActionFactory.COPY.getId(),
 					action);
 		action = getSelectAllAction();
 		if (action != null)
 			actionBars.setGlobalActionHandler(ActionFactory.SELECT_ALL.getId(),
 					action);
 	}

 	/**
 	 * Fills the tool bar.
 	 * <p>
 	 * Default is to do nothing.
 	 * </p>
 	 *
 	 * @param tbm
 	 *            the tool bar manager
 	 */
 	protected void fillToolBar(IToolBarManager tbm) {
 		tbm.add(fGotoInputAction);
 	}

 	private void inititalizeColors() {
 		if (getSite().getShell().isDisposed())
 			return;
 		Display display = getSite().getShell().getDisplay();
 		if (display == null || display.isDisposed())
 			return;
 		setForeground(display.getSystemColor(SWT.COLOR_INFO_FOREGROUND));
 		ColorRegistry registry = JFaceResources.getColorRegistry();
 		registry.addListener(this);
 		fBackgroundColorRGB = registry.getRGB(getBackgroundColorKey());
 		Color bgColor;
 		if (fBackgroundColorRGB == null) {
 			bgColor = display.getSystemColor(SWT.COLOR_INFO_BACKGROUND);
 			fBackgroundColorRGB = bgColor.getRGB();
 		} else {
 			bgColor = new Color(display, fBackgroundColorRGB);
 			fBackgroundColor = bgColor;
 		}
 		setBackground(bgColor);
 	}

 	/**
 	 * The preference key for the background color.
 	 *
 	 * @return the background color key
 	 *
 	 */
 	abstract protected String getBackgroundColorKey();

 	@Override
 	public void propertyChange(PropertyChangeEvent event) {
 		if (getBackgroundColorKey().equals(event.getProperty()))
 			inititalizeColors();
 	}

 	/**
 	 * Start to listen for selection changes.
 	 */
 	protected void startListeningForSelectionChanges() {
 		getSite().getPage().addPostSelectionListener(this);
 	}

 	/**
 	 * Stop to listen for selection changes.
 	 */
 	protected void stopListeningForSelectionChanges() {
 		getSite().getPage().removePostSelectionListener(this);
 	}

 	@Override
 	public void selectionChanged(IWorkbenchPart part, ISelection selection) {
 		if (part.equals(this))
 			return;
 		computeAndSetInput(part);
 	}

 	/**
 	 * Tells whether the new input should be ignored if the current input is the
 	 * same.
 	 *
 	 * @param je
 	 *            the new input
 	 * @param selection
 	 *            the current selection from the part that provides the input
 	 * @return <code>true</code> if the new input should be ignored
 	 */
 	protected boolean isIgnoringNewInput(Object je, IWorkbenchPart part,
 			ISelection selection) {
 		return fCurrentViewInput != null && fCurrentViewInput.equals(je)
 				&& je != null;
 	}

 	/**
 	 * Finds and returns the Script element selected in the given part.
 	 *
 	 * @param part
 	 *            the workbench part for which to find the selected Script
 	 *            element
 	 * @param selection
 	 *            the selection
 	 * @return the selected Script element
 	 */
 	protected Object findSelectedModelElement(IWorkbenchPart part,
 			ISelection selection) {
 		try {
 			if (isValidWorkbenchPart(part)
 					&& selection instanceof ITextSelection) {
 				final IEditorPart editor = (IEditorPart) part;
 				IModelElement[] elements = TextSelectionConverter
 						.codeResolve(editor, (ITextSelection) selection);
 				if (elements != null && elements.length > 0) {
 					return elements.length == 1 ? elements[0]
 							: (Object) new ModelElementArray(elements);
 				}
 			} else if (selection instanceof IStructuredSelection) {
 				Object element = SelectionUtil.getSingleElement(selection);
 				return findModelElement(element);
 			}
 		} catch (ModelException e) {
 			DLTKUIPlugin.log(e);
 		}
 		return null;
 	}

 	/**
 	 * Checks that specified {@link IWorkbenchPart} is an {@link ITextEditor}
 	 * and is suitable to retrieve selected {@link IModelElement}s
 	 *
 	 * @param part
 	 * @return
 	 */
 	protected boolean isValidWorkbenchPart(IWorkbenchPart part) {
 		return part instanceof IEditorPart;
 	}

 	/**
 	 * Tries to get a Script element out of the given element.
 	 *
 	 * @param element
 	 *            an object
 	 * @return the Script element represented by the given element or
 	 *         <code>null</code>
 	 */
 	private IModelElement findModelElement(Object element) {
 		if (element != null && element instanceof IAdaptable) {
 			return ((IAdaptable) element).getAdapter(IModelElement.class);
 		}
 		return null;
 	}

 	/*
 	 * @see IWorkbenchPart#dispose()
 	 */
 	@Override
 	final public void dispose() {
 		// cancel possible running computation
 		fComputeCount++;
 		if (fContextActivation != null) {
 			IContextService ctxService = getSite()
 					.getService(IContextService.class);
 			if (ctxService != null) {
 				ctxService.deactivateContext(fContextActivation);
 			}
 		}
 		getSite().getWorkbenchWindow().getPartService()
 				.removePartListener(fPartListener);
 		ISelectionProvider provider = getSelectionProvider();
 		if (provider != null)
 			provider.removeSelectionChangedListener(fCopyToClipboardAction);
 		JFaceResources.getColorRegistry().removeListener(this);
 		fBackgroundColorRGB = null;
 		if (fBackgroundColor != null) {
 			fBackgroundColor.dispose();
 			fBackgroundColor = null;
 		}
 		internalDispose();
 	}

 	/*
 	 * @see IWorkbenchPart#dispose()
 	 */
 	abstract protected void internalDispose();

 	/**
 	 * Determines all necessary details and delegates the computation into a
 	 * background thread.
 	 *
 	 * @param part
 	 *            the workbench part
 	 */
 	private void computeAndSetInput(final IWorkbenchPart part) {
 		final int currentCount = ++fComputeCount;
 		ISelectionProvider provider = part.getSite().getSelectionProvider();
 		if (provider == null)
 			return;
 		final ISelection selection = provider.getSelection();
 		if (selection == null || selection.isEmpty())
 			return;
 		Thread thread = new Thread("Info view input computer") { //$NON-NLS-1$
 			@Override
 			public void run() {
 				if (currentCount != fComputeCount)
 					return;
 				Object je = findSelectedModelElement(part, selection);
 				Object tmp = null;
 				if (je != null) {
 					tmp = je;
 				} else {
 					if (part instanceof ITextEditor
 							&& selection instanceof ITextSelection) {
 						ITextEditor edit = (ITextEditor) part;
 						IDocument document = edit.getDocumentProvider()
 								.getDocument(edit.getEditorInput());
 						IRegion reg = ScriptWordFinder.findWord(document,
 								((ITextSelection) selection).getOffset());
 						if (reg != null) {
 							try {
 								tmp = new KeywordInput(
 										document.get(reg.getOffset(),
 												reg.getLength()),
 										EditorUtility
 												.getEditorInputModelElement(
 														edit, false));
 							} catch (BadLocationException e) {
 								tmp = null;
 							}
 						}
 					}
 				}

 				final Object src = tmp;

 				if (isIgnoringNewInput(src, part, selection))
 					return;

 				// The actual computation
 				final Object input = computeInput(src);
 				if (input == null)
 					return;
 				Shell shell = getSite().getShell();
 				if (shell.isDisposed())
 					return;
 				Display display = shell.getDisplay();
 				if (display.isDisposed())
 					return;
 				display.asyncExec(() -> {
 					if (fComputeCount != currentCount
 							|| getViewSite().getShell().isDisposed())
 						return;
 					fCurrentViewInput = src;
 					doSetInput(input);
 				});

 			}
 		};
 		thread.setDaemon(true);
 		thread.setPriority(Thread.MIN_PRIORITY);
 		thread.start();
 	}

 	private void doSetInput(Object input) {
 		setInput(input);
 		Object in = getInput();
 		fGotoInputAction.setEnabled(in instanceof IModelElement);
 		if (in instanceof IModelElement) {
 			IModelElement me = (IModelElement) in;
 			setContentDescription(ScriptElementLabels.getDefault()
 					.getElementLabel(me, TITLE_FLAGS));
 			setTitleToolTip(ScriptElementLabels.getDefault().getElementLabel(me,
 					TOOLTIP_LABEL_FLAGS));
 		} else if (in instanceof ModelElementArray) {
 			final ModelElementArray array = (ModelElementArray) in;
 			setContentDescription(array.getContentDescription());
 			setTitleToolTip(array.getTitleTooltip());
 		} else if (in instanceof KeywordInput) {
 			final KeywordInput keyword = (KeywordInput) in;
 			setContentDescription(keyword.getValue());
 			setTitleToolTip(keyword.getValue());
 		} else {
 			setContentDescription(in.toString());
 			setTitleToolTip(in.toString());
 		}
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2000, 2017 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* xored software, Inc. - initial API and Implementation (Andrei Sobolev)
	* xored software, Inc. - Patch 228846 (Alex Panchenko <alex@xored.com>)
	*******************************************************************************/
	package org.eclipse.dltk.ui.infoviews;

	import org.eclipse.core.runtime.IAdaptable;
	import org.eclipse.dltk.core.IModelElement;
	import org.eclipse.dltk.core.ModelException;
	import org.eclipse.dltk.internal.ui.editor.EditorUtility;
	import org.eclipse.dltk.internal.ui.text.ScriptWordFinder;
	import org.eclipse.dltk.internal.ui.util.SelectionUtil;
	import org.eclipse.dltk.ui.DLTKUIPlugin;
	import org.eclipse.dltk.ui.IContextMenuConstants;
	import org.eclipse.dltk.ui.ScriptElementLabels;
	import org.eclipse.dltk.ui.actions.SelectionDispatchAction;
	import org.eclipse.jface.action.IAction;
	import org.eclipse.jface.action.IMenuListener;
	import org.eclipse.jface.action.IMenuManager;
	import org.eclipse.jface.action.IToolBarManager;
	import org.eclipse.jface.action.MenuManager;
	import org.eclipse.jface.action.Separator;
	import org.eclipse.jface.resource.ColorRegistry;
	import org.eclipse.jface.resource.JFaceResources;
	import org.eclipse.jface.text.BadLocationException;
	import org.eclipse.jface.text.IDocument;
	import org.eclipse.jface.text.IRegion;
	import org.eclipse.jface.text.ITextSelection;
	import org.eclipse.jface.util.IPropertyChangeListener;
	import org.eclipse.jface.util.PropertyChangeEvent;
	import org.eclipse.jface.viewers.ISelection;
	import org.eclipse.jface.viewers.ISelectionProvider;
	import org.eclipse.jface.viewers.IStructuredSelection;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.graphics.Color;
	import org.eclipse.swt.graphics.RGB;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.swt.widgets.Display;
	import org.eclipse.swt.widgets.Menu;
	import org.eclipse.swt.widgets.Shell;
	import org.eclipse.ui.IActionBars;
	import org.eclipse.ui.IEditorPart;
	import org.eclipse.ui.IPartListener2;
	import org.eclipse.ui.ISelectionListener;
	import org.eclipse.ui.IWorkbenchPart;
	import org.eclipse.ui.IWorkbenchPartReference;
	import org.eclipse.ui.PlatformUI;
	import org.eclipse.ui.actions.ActionFactory;
	import org.eclipse.ui.contexts.IContextActivation;
	import org.eclipse.ui.contexts.IContextService;
	import org.eclipse.ui.part.ViewPart;
	import org.eclipse.ui.texteditor.ITextEditor;
	import org.eclipse.ui.texteditor.ITextEditorActionConstants;

	/**
	* Abstract class for views which show information for a given element.
	*
	*/
	public abstract class AbstractInfoView extends ViewPart
	implements ISelectionListener, IMenuListener, IPropertyChangeListener {

	/**
	* @since 2.0
	*/
	protected static class KeywordInput {
	private final String value;
	private final IModelElement context;

	public KeywordInput(String value, IModelElement context) {
	this.value = value;
	this.context = context;
	}

	public String getValue() {
	return value;
	}

	public IModelElement getContext() {
	return context;
	}

	}

	/** ScriptElementLabels flags used for the title */
	private final long TITLE_FLAGS = ScriptElementLabels.ALL_FULLY_QUALIFIED
	\| ScriptElementLabels.M_APP_RETURNTYPE
	\| ScriptElementLabels.F_APP_TYPE_SIGNATURE
	\| ScriptElementLabels.M_PARAMETER_TYPES
	\| ScriptElementLabels.M_PARAMETER_NAMES
	\| ScriptElementLabels.M_EXCEPTIONS
	\| ScriptElementLabels.F_PRE_TYPE_SIGNATURE
	\| ScriptElementLabels.M_PRE_TYPE_PARAMETERS
	\| ScriptElementLabels.T_TYPE_PARAMETERS
	\| ScriptElementLabels.USE_RESOLVED;
	// private final long LOCAL_VARIABLE_TITLE_FLAGS = TITLE_FLAGS &
	// ~ScriptElementLabels.F_FULLY_QUALIFIED \|
	// ScriptElementLabels.F_POST_QUALIFIED;
	/** ScriptElementLabels flags used for the tool tip text */
	private static final long TOOLTIP_LABEL_FLAGS = ScriptElementLabels.DEFAULT_QUALIFIED
	\| ScriptElementLabels.ROOT_POST_QUALIFIED
	\| ScriptElementLabels.APPEND_ROOT_PATH
	\| ScriptElementLabels.M_PARAMETER_TYPES
	\| ScriptElementLabels.M_PARAMETER_NAMES
	\| ScriptElementLabels.M_APP_RETURNTYPE
	\| ScriptElementLabels.M_EXCEPTIONS
	\| ScriptElementLabels.F_APP_TYPE_SIGNATURE
	\| ScriptElementLabels.M_APP_RETURNTYPE
	\| ScriptElementLabels.T_TYPE_PARAMETERS;
	/*
	* @see IPartListener2
	*/
	private IPartListener2 fPartListener = new IPartListener2() {
	@Override
	public void partVisible(IWorkbenchPartReference ref) {
	if (ref.getId().equals(getSite().getId())) {
	IWorkbenchPart activePart = ref.getPage().getActivePart();
	if (activePart != null)
	selectionChanged(activePart, ref.getPage().getSelection());
	startListeningForSelectionChanges();
	}
	}

	@Override
	public void partHidden(IWorkbenchPartReference ref) {
	if (ref.getId().equals(getSite().getId()))
	stopListeningForSelectionChanges();
	}

	@Override
	public void partInputChanged(IWorkbenchPartReference ref) {
	if (!ref.getId().equals(getSite().getId()))
	computeAndSetInput(ref.getPart(false));
	}

	@Override
	public void partActivated(IWorkbenchPartReference ref) {
	}

	@Override
	public void partBroughtToTop(IWorkbenchPartReference ref) {
	}

	@Override
	public void partClosed(IWorkbenchPartReference ref) {
	}

	@Override
	public void partDeactivated(IWorkbenchPartReference ref) {
	}

	@Override
	public void partOpened(IWorkbenchPartReference ref) {
	}
	};
	/** The current input. */
	protected Object fCurrentViewInput;
	/** The copy to clipboard action. */
	private SelectionDispatchAction fCopyToClipboardAction;
	/** The goto input action. */
	private GotoInputAction fGotoInputAction;
	/** Counts the number of background computation requests. */
	private volatile int fComputeCount;
	private IContextActivation fContextActivation;
	/**
	* Background color.
	*
	*
	*/
	private Color fBackgroundColor;
	private RGB fBackgroundColorRGB;

	/**
	* Set the input of this view.
	*
	* @param input
	* the input object
	*/
	abstract protected void setInput(Object input);

	/**
	* Computes the input for this view based on the given element.
	*
	* @param element
	* the element from which to compute the input
	* @return the input or <code>null</code> if the input was not computed
	* successfully
	*/
	abstract protected Object computeInput(Object element);

	/**
	* Create the part control.
	*
	* @param parent
	* the parent control
	* @see IWorkbenchPart#createPartControl(org.eclipse.swt.widgets.Composite)
	*/
	abstract protected void internalCreatePartControl(Composite parent);

	/**
	* Set the view's foreground color.
	*
	* @param color
	* the SWT color
	*/
	abstract protected void setForeground(Color color);

	/**
	* Set the view's background color.
	*
	* @param color
	* the SWT color
	*/
	abstract protected void setBackground(Color color);

	/**
	* Returns the view's primary control.
	*
	* @return the primary control
	*/
	protected abstract Control getControl();

	/**
	* Returns the context ID for the Help system
	*
	* @return the string used as ID for the Help context
	*
	*/
	abstract protected String getHelpContextId();

	/*
	* @see IWorkbenchPart#createPartControl(org.eclipse.swt.widgets.Composite)
	*/
	@Override
	public final void createPartControl(Composite parent) {
	internalCreatePartControl(parent);
	inititalizeColors();
	getSite().getWorkbenchWindow().getPartService()
	.addPartListener(fPartListener);
	createActions();
	createContextMenu();
	fillActionBars(getViewSite().getActionBars());
	IContextService ctxService = getSite()
	.getService(IContextService.class);
	if (ctxService != null) {
	fContextActivation = ctxService
	.activateContext(DLTKUIPlugin.CONTEXT_VIEWS);
	}
	PlatformUI.getWorkbench().getHelpSystem().setHelp(getControl(),
	getHelpContextId());
	}

	/**
	* Creates the actions and action groups for this view.
	*/
	protected void createActions() {
	fGotoInputAction = new GotoInputAction(this);
	fGotoInputAction.setEnabled(false);
	fCopyToClipboardAction = new CopyToClipboardAction(getViewSite());
	ISelectionProvider provider = getSelectionProvider();
	if (provider != null)
	provider.addSelectionChangedListener(fCopyToClipboardAction);
	}

	/**
	* Creates the context menu for this view.
	*/
	protected void createContextMenu() {
	MenuManager menuManager = new MenuManager("#PopupMenu"); //$NON-NLS-1$
	menuManager.setRemoveAllWhenShown(true);
	menuManager.addMenuListener(this);
	Menu contextMenu = menuManager.createContextMenu(getControl());
	getControl().setMenu(contextMenu);
	getSite().registerContextMenu(menuManager, getSelectionProvider());
	}

	@Override
	public void menuAboutToShow(IMenuManager menu) {
	menu.add(new Separator(IContextMenuConstants.GROUP_OPEN));
	menu.add(new Separator(ITextEditorActionConstants.GROUP_EDIT));
	menu.add(new Separator(IContextMenuConstants.GROUP_ADDITIONS));
	IAction action;
	action = getCopyToClipboardAction();
	if (action != null)
	menu.appendToGroup(ITextEditorActionConstants.GROUP_EDIT, action);
	action = getSelectAllAction();
	if (action != null)
	menu.appendToGroup(ITextEditorActionConstants.GROUP_EDIT, action);
	menu.appendToGroup(IContextMenuConstants.GROUP_OPEN, fGotoInputAction);
	}

	protected IAction getSelectAllAction() {
	return null;
	}

	protected IAction getCopyToClipboardAction() {
	return fCopyToClipboardAction;
	}

	/**
	* Returns the input of this view.
	*
	* @return input the input object or <code>null</code> if not input is set
	*/
	protected Object getInput() {
	return fCurrentViewInput;
	}

	// Helper method
	ISelectionProvider getSelectionProvider() {
	return getViewSite().getSelectionProvider();
	}

	/**
	* Fills the actions bars.
	* <p>
	* Subclasses may extend.
	*
	* @param actionBars
	* the action bars
	*/
	protected void fillActionBars(IActionBars actionBars) {
	IToolBarManager toolBar = actionBars.getToolBarManager();
	fillToolBar(toolBar);
	IAction action;
	action = getCopyToClipboardAction();
	if (action != null)
	actionBars.setGlobalActionHandler(ActionFactory.COPY.getId(),
	action);
	action = getSelectAllAction();
	if (action != null)
	actionBars.setGlobalActionHandler(ActionFactory.SELECT_ALL.getId(),
	action);
	}

	/**
	* Fills the tool bar.
	* <p>
	* Default is to do nothing.
	* </p>
	*
	* @param tbm
	* the tool bar manager
	*/
	protected void fillToolBar(IToolBarManager tbm) {
	tbm.add(fGotoInputAction);
	}

	private void inititalizeColors() {
	if (getSite().getShell().isDisposed())
	return;
	Display display = getSite().getShell().getDisplay();
	if (display == null \|\| display.isDisposed())
	return;
	setForeground(display.getSystemColor(SWT.COLOR_INFO_FOREGROUND));
	ColorRegistry registry = JFaceResources.getColorRegistry();
	registry.addListener(this);
	fBackgroundColorRGB = registry.getRGB(getBackgroundColorKey());
	Color bgColor;
	if (fBackgroundColorRGB == null) {
	bgColor = display.getSystemColor(SWT.COLOR_INFO_BACKGROUND);
	fBackgroundColorRGB = bgColor.getRGB();
	} else {
	bgColor = new Color(display, fBackgroundColorRGB);
	fBackgroundColor = bgColor;
	}
	setBackground(bgColor);
	}

	/**
	* The preference key for the background color.
	*
	* @return the background color key
	*
	*/
	abstract protected String getBackgroundColorKey();

	@Override
	public void propertyChange(PropertyChangeEvent event) {
	if (getBackgroundColorKey().equals(event.getProperty()))
	inititalizeColors();
	}

	/**
	* Start to listen for selection changes.
	*/
	protected void startListeningForSelectionChanges() {
	getSite().getPage().addPostSelectionListener(this);
	}

	/**
	* Stop to listen for selection changes.
	*/
	protected void stopListeningForSelectionChanges() {
	getSite().getPage().removePostSelectionListener(this);
	}

	@Override
	public void selectionChanged(IWorkbenchPart part, ISelection selection) {
	if (part.equals(this))
	return;
	computeAndSetInput(part);
	}

	/**
	* Tells whether the new input should be ignored if the current input is the
	* same.
	*
	* @param je
	* the new input
	* @param selection
	* the current selection from the part that provides the input
	* @return <code>true</code> if the new input should be ignored
	*/
	protected boolean isIgnoringNewInput(Object je, IWorkbenchPart part,
	ISelection selection) {
	return fCurrentViewInput != null && fCurrentViewInput.equals(je)
	&& je != null;
	}

	/**
	* Finds and returns the Script element selected in the given part.
	*
	* @param part
	* the workbench part for which to find the selected Script
	* element
	* @param selection
	* the selection
	* @return the selected Script element
	*/
	protected Object findSelectedModelElement(IWorkbenchPart part,
	ISelection selection) {
	try {
	if (isValidWorkbenchPart(part)
	&& selection instanceof ITextSelection) {
	final IEditorPart editor = (IEditorPart) part;
	IModelElement[] elements = TextSelectionConverter
	.codeResolve(editor, (ITextSelection) selection);
	if (elements != null && elements.length > 0) {
	return elements.length == 1 ? elements[0]
	: (Object) new ModelElementArray(elements);
	}
	} else if (selection instanceof IStructuredSelection) {
	Object element = SelectionUtil.getSingleElement(selection);
	return findModelElement(element);
	}
	} catch (ModelException e) {
	DLTKUIPlugin.log(e);
	}
	return null;
	}

	/**
	* Checks that specified {@link IWorkbenchPart} is an {@link ITextEditor}
	* and is suitable to retrieve selected {@link IModelElement}s
	*
	* @param part
	* @return
	*/
	protected boolean isValidWorkbenchPart(IWorkbenchPart part) {
	return part instanceof IEditorPart;
	}

	/**
	* Tries to get a Script element out of the given element.
	*
	* @param element
	* an object
	* @return the Script element represented by the given element or
	* <code>null</code>
	*/
	private IModelElement findModelElement(Object element) {
	if (element != null && element instanceof IAdaptable) {
	return ((IAdaptable) element).getAdapter(IModelElement.class);
	}
	return null;
	}

	/*
	* @see IWorkbenchPart#dispose()
	*/
	@Override
	final public void dispose() {
	// cancel possible running computation
	fComputeCount++;
	if (fContextActivation != null) {
	IContextService ctxService = getSite()
	.getService(IContextService.class);
	if (ctxService != null) {
	ctxService.deactivateContext(fContextActivation);
	}
	}
	getSite().getWorkbenchWindow().getPartService()
	.removePartListener(fPartListener);
	ISelectionProvider provider = getSelectionProvider();
	if (provider != null)
	provider.removeSelectionChangedListener(fCopyToClipboardAction);
	JFaceResources.getColorRegistry().removeListener(this);
	fBackgroundColorRGB = null;
	if (fBackgroundColor != null) {
	fBackgroundColor.dispose();
	fBackgroundColor = null;
	}
	internalDispose();
	}

	/*
	* @see IWorkbenchPart#dispose()
	*/
	abstract protected void internalDispose();

	/**
	* Determines all necessary details and delegates the computation into a
	* background thread.
	*
	* @param part
	* the workbench part
	*/
	private void computeAndSetInput(final IWorkbenchPart part) {
	final int currentCount = ++fComputeCount;
	ISelectionProvider provider = part.getSite().getSelectionProvider();
	if (provider == null)
	return;
	final ISelection selection = provider.getSelection();
	if (selection == null \|\| selection.isEmpty())
	return;
	Thread thread = new Thread("Info view input computer") { //$NON-NLS-1$
	@Override
	public void run() {
	if (currentCount != fComputeCount)
	return;
	Object je = findSelectedModelElement(part, selection);
	Object tmp = null;
	if (je != null) {
	tmp = je;
	} else {
	if (part instanceof ITextEditor
	&& selection instanceof ITextSelection) {
	ITextEditor edit = (ITextEditor) part;
	IDocument document = edit.getDocumentProvider()
	.getDocument(edit.getEditorInput());
	IRegion reg = ScriptWordFinder.findWord(document,
	((ITextSelection) selection).getOffset());
	if (reg != null) {
	try {
	tmp = new KeywordInput(
	document.get(reg.getOffset(),
	reg.getLength()),
	EditorUtility
	.getEditorInputModelElement(
	edit, false));
	} catch (BadLocationException e) {
	tmp = null;
	}
	}
	}
	}

	final Object src = tmp;

	if (isIgnoringNewInput(src, part, selection))
	return;

	// The actual computation
	final Object input = computeInput(src);
	if (input == null)
	return;
	Shell shell = getSite().getShell();
	if (shell.isDisposed())
	return;
	Display display = shell.getDisplay();
	if (display.isDisposed())
	return;
	display.asyncExec(() -> {
	if (fComputeCount != currentCount
	\|\| getViewSite().getShell().isDisposed())
	return;
	fCurrentViewInput = src;
	doSetInput(input);
	});

	}
	};
	thread.setDaemon(true);
	thread.setPriority(Thread.MIN_PRIORITY);
	thread.start();
	}

	private void doSetInput(Object input) {
	setInput(input);
	Object in = getInput();
	fGotoInputAction.setEnabled(in instanceof IModelElement);
	if (in instanceof IModelElement) {
	IModelElement me = (IModelElement) in;
	setContentDescription(ScriptElementLabels.getDefault()
	.getElementLabel(me, TITLE_FLAGS));
	setTitleToolTip(ScriptElementLabels.getDefault().getElementLabel(me,
	TOOLTIP_LABEL_FLAGS));
	} else if (in instanceof ModelElementArray) {
	final ModelElementArray array = (ModelElementArray) in;
	setContentDescription(array.getContentDescription());
	setTitleToolTip(array.getTitleTooltip());
	} else if (in instanceof KeywordInput) {
	final KeywordInput keyword = (KeywordInput) in;
	setContentDescription(keyword.getValue());
	setTitleToolTip(keyword.getValue());
	} else {
	setContentDescription(in.toString());
	setTitleToolTip(in.toString());
	}
	}
	}