net.sf.wdte.ui.views.outline.ProblemsLabelDecorator.java Source code

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Here is the source code for net.sf.wdte.ui.views.outline.ProblemsLabelDecorator.java

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/*
 * Copyright (c) 2004 Christopher Lenz and others
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     Christopher Lenz - initial implementation
 * 
 * $Id: ProblemsLabelDecorator.java,v 1.2 2004/02/28 15:39:40 cell Exp $
 */

package net.sf.wdte.ui.views.outline;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import net.sf.wdte.core.model.ISourceReference;
import net.sf.wdte.ui.WebUI;
import net.sf.wdte.ui.views.util.ImageDescriptorRegistry;
import net.sf.wdte.ui.views.util.ImageImageDescriptor;
import net.sf.wdte.ui.views.util.OverlayImageDescriptor;

import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.Position;
import org.eclipse.jface.text.source.Annotation;
import org.eclipse.jface.text.source.IAnnotationModel;
import org.eclipse.jface.viewers.ILabelDecorator;
import org.eclipse.jface.viewers.LabelProvider;
import org.eclipse.swt.graphics.Image;
import org.eclipse.ui.IEditorInput;
import org.eclipse.ui.texteditor.ITextEditor;

/**
 * Label decorator for the outline page that adds error and warning overlay
 * icons to elements in the outline. The information is retrieved from the 
 * annotation model corresponding to the input of the associated text editor.
 */
public class ProblemsLabelDecorator extends LabelProvider implements ILabelDecorator {

    // Constants ---------------------------------------------------------------

    private static final String ANNOTATION_TYPE_ERROR = "org.eclipse.ui.workbench.texteditor.error"; //$NON-NLS-1$

    private static final String ANNOTATION_TYPE_WARNING = "org.eclipse.ui.workbench.texteditor.warning"; //$NON-NLS-1$

    // Instance Variables ------------------------------------------------------

    /** The associated text editor if the decorator is used in the outline. */
    private ITextEditor editor;

    /** Registry of icons and overlay icons. */
    private ImageDescriptorRegistry registry = new ImageDescriptorRegistry();

    // Constructors ------------------------------------------------------------

    /**
     * Constructor.
     * 
     * @param editor the associated text editor
     */
    public ProblemsLabelDecorator(ITextEditor editor) {
        this.editor = editor;
    }

    // ILabelDecorator Implementation ------------------------------------------

    /* 
     * @see org.eclipse.jface.viewers.IBaseLabelProvider#dispose()
     */
    @Override
    public void dispose() {
        super.dispose();
        registry.dispose();
    }

    /* 
     * @see ILabelDecorator#decorateImage(Image, Object)
     */
    @Override
    public Image decorateImage(Image image, Object element) {
        Annotation annotations[] = getAssociatedAnnotations((ISourceReference) element);
        ImageDescriptor overlay = null;
        for (int i = 0; i < annotations.length; i++) {
            if (isError(annotations[i])) {
                overlay = WebUI.getDefault().getImageRegistry().getDescriptor(WebUI.ICON_OVERLAY_ERROR);
            } else if (isWarning(annotations[i])) {
                overlay = WebUI.getDefault().getImageRegistry().getDescriptor(WebUI.ICON_OVERLAY_WARNING);
            }
        }
        if (overlay != null) {
            ImageDescriptor base = new ImageImageDescriptor(image);
            return registry.get(new OverlayImageDescriptor(base,
                    new ImageDescriptor[][] { null, null, { overlay }, null }, null));
        } else {
        }
        return image;
    }

    /* 
     * @see ILabelDecorator#decorateText(String, Object)
     */
    @Override
    public String decorateText(String text, Object element) {
        return text;
    }

    // Private Methods ---------------------------------------------------------

    /**
     * Returns all annotations associated with the given model element.
     * 
     * @param element the model element for which annotations should be
     *        collected
     * @return an array containing all annotations for the given element, or an
     *         empty array if no annotations are found
     */
    private Annotation[] getAssociatedAnnotations(ISourceReference element) {
        List retVal = new ArrayList();
        if (editor != null) {
            IEditorInput input = editor.getEditorInput();
            IAnnotationModel model = editor.getDocumentProvider().getAnnotationModel(input);
            for (Iterator i = model.getAnnotationIterator(); i.hasNext();) {
                Annotation annotation = (Annotation) i.next();
                Position pos = model.getPosition(annotation);
                if (isInside(pos.getOffset(), element)) {
                    retVal.add(annotation);
                }
            }
        }
        return (Annotation[]) retVal.toArray(new Annotation[retVal.size()]);
    }

    /**
     * Determines whether the given annotation is an error.
     * 
     * @param annotation the annotation to check
     * @return <tt>true</tt> if the annotation is to be displayed as an error,
     *         <tt>false</tt> otherwise
     */
    private boolean isError(Annotation annotation) {
        return ANNOTATION_TYPE_ERROR.equals(annotation.getType());
    }

    /**
     * Determines whether the given annotation is a warning.
     * 
     * @param annotation the annotation to check
     * @return <tt>true</tt> if the annotation is to be displayed as a warning,
     *         <tt>false</tt> otherwise
     */
    private boolean isWarning(Annotation annotation) {
        return ANNOTATION_TYPE_WARNING.equals(annotation.getType());
    }

    /**
     * Tests if the given position is inside the source region of a model
     * element.
     * 
     * @param pos the position to be tested
     * @param element the source element
     * @return boolean <tt>true</tt> if position is located inside the
     *         element, otherwise <tt>false</tt>
     */
    private boolean isInside(int pos, ISourceReference element) {
        IRegion region = element.getSourceRegion();
        if (region != null) {
            int offset = region.getOffset();
            return ((offset <= pos) && (offset + region.getLength() > pos));
        }
        return false;
    }

}