org.eclipse.dltk.mod.ui.viewsupport.ProblemTableViewer.java Source code

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Here is the source code for org.eclipse.dltk.mod.ui.viewsupport.ProblemTableViewer.java

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/*******************************************************************************
 * Copyright (c) 2000, 2007 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
 *
     
 *******************************************************************************/

package org.eclipse.dltk.mod.ui.viewsupport;

import java.util.ArrayList;

import org.eclipse.core.resources.IResource;
import org.eclipse.dltk.mod.internal.ui.IWorkingCopyProvider;
import org.eclipse.dltk.mod.ui.ProblemsLabelDecorator.ProblemsLabelChangedEvent;
import org.eclipse.jface.viewers.IBaseLabelProvider;
import org.eclipse.jface.viewers.LabelProviderChangedEvent;
import org.eclipse.jface.viewers.TableViewer;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Item;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.Widget;

/**
 * Extends a  TableViewer to allow more performance when showing error ticks.
 * A <code>ProblemItemMapper</code> is contained that maps all items in
 * the tree to underlying resource
 */
public class ProblemTableViewer extends TableViewer implements ResourceToItemsMapper.IContentViewerAccessor {

    protected ResourceToItemsMapper fResourceToItemsMapper;

    /**
     * Constructor for ProblemTableViewer.
     * @param parent
     */
    public ProblemTableViewer(Composite parent) {
        super(parent);
        initMapper();
    }

    /**
     * Constructor for ProblemTableViewer.
     * @param parent
     * @param style
     */
    public ProblemTableViewer(Composite parent, int style) {
        super(parent, style);
        initMapper();
    }

    /**
     * Constructor for ProblemTableViewer.
     * @param table
     */
    public ProblemTableViewer(Table table) {
        super(table);
        initMapper();
    }

    private void initMapper() {
        fResourceToItemsMapper = new ResourceToItemsMapper(this);
    }

    public void doUpdateItem(Widget item) {
        doUpdateItem(item, item.getData(), true);
    }

    /*
     * @see StructuredViewer#mapElement(Object, Widget)
     */
    protected void mapElement(Object element, Widget item) {
        super.mapElement(element, item);
        if (item instanceof Item) {
            fResourceToItemsMapper.addToMap(element, (Item) item);
        }
    }

    /*
     * @see StructuredViewer#unmapElement(Object, Widget)
     */
    protected void unmapElement(Object element, Widget item) {
        if (item instanceof Item) {
            fResourceToItemsMapper.removeFromMap(element, (Item) item);
        }
        super.unmapElement(element, item);
    }

    /*
     * @see StructuredViewer#unmapAllElements()
     */
    protected void unmapAllElements() {
        fResourceToItemsMapper.clearMap();
        super.unmapAllElements();
    }

    /*
     * @see ContentViewer#handleLabelProviderChanged(LabelProviderChangedEvent)
     */
    protected void handleLabelProviderChanged(LabelProviderChangedEvent event) {
        if (event instanceof ProblemsLabelChangedEvent) {
            ProblemsLabelChangedEvent e = (ProblemsLabelChangedEvent) event;
            if (!e.isMarkerChange() && canIgnoreChangesFromAnnotionModel()) {
                return;
            }
        }

        Object[] changed = event.getElements();
        if (changed != null && !fResourceToItemsMapper.isEmpty()) {
            ArrayList others = new ArrayList(changed.length);
            for (int i = 0; i < changed.length; i++) {
                Object curr = changed[i];
                if (curr instanceof IResource) {
                    fResourceToItemsMapper.resourceChanged((IResource) curr);
                } else {
                    others.add(curr);
                }
            }
            if (others.isEmpty()) {
                return;
            }
            event = new LabelProviderChangedEvent((IBaseLabelProvider) event.getSource(), others.toArray());
        }
        super.handleLabelProviderChanged(event);
    }

    /**
     * Answers whether this viewer can ignore label provider changes resulting from
     * marker changes in annotation models
     */
    private boolean canIgnoreChangesFromAnnotionModel() {
        Object contentProvider = getContentProvider();
        return contentProvider instanceof IWorkingCopyProvider
                && !((IWorkingCopyProvider) contentProvider).providesWorkingCopies();
    }
}