org.eclipse.jdt.ui.examples.JavaElementLightweightDecorator.java Source code

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Here is the source code for org.eclipse.jdt.ui.examples.JavaElementLightweightDecorator.java

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/*******************************************************************************
 * Copyright (c) 2000, 2009 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jdt.ui.examples;

import java.util.HashSet;
import java.util.Set;

import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.widgets.Display;

import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Status;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IResource;

import org.eclipse.core.filebuffers.FileBuffers;
import org.eclipse.core.filebuffers.IFileBuffer;
import org.eclipse.core.filebuffers.IFileBufferListener;
import org.eclipse.core.filebuffers.LocationKind;

import org.eclipse.jface.resource.FontRegistry;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.viewers.IDecoration;
import org.eclipse.jface.viewers.ILightweightLabelDecorator;
import org.eclipse.jface.viewers.LabelProvider;
import org.eclipse.jface.viewers.LabelProviderChangedEvent;

import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.progress.UIJob;

import org.eclipse.jdt.core.IClassFile;
import org.eclipse.jdt.core.ICompilationUnit;
import org.eclipse.jdt.core.IJavaElement;

/**
 *
 */
public class JavaElementLightweightDecorator extends LabelProvider implements ILightweightLabelDecorator {

    private class FileBufferListener implements IFileBufferListener {
        /* (non-Javadoc)
         * @see org.eclipse.core.filebuffers.IFileBufferListener#bufferCreated(org.eclipse.core.filebuffers.IFileBuffer)
         */
        public void bufferCreated(IFileBuffer buffer) {
            if (buffer.getLocation() != null)
                update(buffer.getLocation());
        }

        /* (non-Javadoc)
         * @see org.eclipse.core.filebuffers.IFileBufferListener#bufferDisposed(org.eclipse.core.filebuffers.IFileBuffer)
         */
        public void bufferDisposed(IFileBuffer buffer) {
            if (buffer.getLocation() != null)
                update(buffer.getLocation());
        }

        /* (non-Javadoc)
         * @see org.eclipse.core.filebuffers.IFileBufferListener#bufferContentAboutToBeReplaced(org.eclipse.core.filebuffers.IFileBuffer)
         */
        public void bufferContentAboutToBeReplaced(IFileBuffer buffer) {
        }

        /* (non-Javadoc)
         * @see org.eclipse.core.filebuffers.IFileBufferListener#bufferContentReplaced(org.eclipse.core.filebuffers.IFileBuffer)
         */
        public void bufferContentReplaced(IFileBuffer buffer) {
        }

        /* (non-Javadoc)
         * @see org.eclipse.core.filebuffers.IFileBufferListener#stateChanging(org.eclipse.core.filebuffers.IFileBuffer)
         */
        public void stateChanging(IFileBuffer buffer) {
        }

        /* (non-Javadoc)
         * @see org.eclipse.core.filebuffers.IFileBufferListener#dirtyStateChanged(org.eclipse.core.filebuffers.IFileBuffer, boolean)
         */
        public void dirtyStateChanged(IFileBuffer buffer, boolean isDirty) {
        }

        /* (non-Javadoc)
         * @see org.eclipse.core.filebuffers.IFileBufferListener#stateValidationChanged(org.eclipse.core.filebuffers.IFileBuffer, boolean)
         */
        public void stateValidationChanged(IFileBuffer buffer, boolean isStateValidated) {
        }

        /* (non-Javadoc)
         * @see org.eclipse.core.filebuffers.IFileBufferListener#underlyingFileMoved(org.eclipse.core.filebuffers.IFileBuffer, org.eclipse.core.runtime.IPath)
         */
        public void underlyingFileMoved(IFileBuffer buffer, IPath path) {
        }

        /* (non-Javadoc)
         * @see org.eclipse.core.filebuffers.IFileBufferListener#underlyingFileDeleted(org.eclipse.core.filebuffers.IFileBuffer)
         */
        public void underlyingFileDeleted(IFileBuffer buffer) {
        }

        /* (non-Javadoc)
         * @see org.eclipse.core.filebuffers.IFileBufferListener#stateChangeFailed(org.eclipse.core.filebuffers.IFileBuffer)
         */
        public void stateChangeFailed(IFileBuffer buffer) {
        }
    }

    private Color fColor;
    private Font fBold;
    private FileBufferListener fListener;

    private UIJob fNotifierJob;

    private Set fChangedResources;

    public JavaElementLightweightDecorator() {
        final FontRegistry fontRegistry = PlatformUI.getWorkbench().getThemeManager().getCurrentTheme()
                .getFontRegistry();
        Display.getDefault().syncExec(new Runnable() {
            public void run() {
                fColor = new Color(Display.getDefault(), 100, 100, 100);
                fBold = fontRegistry.getBold(JFaceResources.DEFAULT_FONT);
            }
        });
        fListener = new FileBufferListener();
        FileBuffers.getTextFileBufferManager().addFileBufferListener(fListener);

        fChangedResources = new HashSet();
    }

    /* (non-Javadoc)
     * @see org.eclipse.jface.viewers.ILightweightLabelDecorator#decorate(java.lang.Object, org.eclipse.jface.viewers.IDecoration)
     */
    public void decorate(Object element, IDecoration decoration) {
        IPath path = null;

        if (element instanceof IResource) {
            path = ((IResource) element).getFullPath();
        } else if (element instanceof IClassFile || element instanceof ICompilationUnit) {
            path = ((IJavaElement) element).getPath();
        }
        if (path != null) {
            if (FileBuffers.getTextFileBufferManager().getFileBuffer(path, LocationKind.NORMALIZE) != null) {
                decoration.setFont(fBold);
            }
        }
    }

    private void update(IPath location) {
        IFile file = FileBuffers.getWorkspaceFileAtLocation(location);
        if (file != null) {
            boolean hasChanges = false;
            synchronized (this) {
                hasChanges = fChangedResources.add(file);
            }
            if (hasChanges) {
                if (fNotifierJob == null) {
                    fNotifierJob = new UIJob(Display.getDefault(), "Update Java test decorations") {
                        public IStatus runInUIThread(IProgressMonitor monitor) {
                            runPendingUpdates();
                            return Status.OK_STATUS;
                        }
                    };
                    fNotifierJob.setSystem(true);
                }
                fNotifierJob.schedule();
            }
        }
    }

    private void runPendingUpdates() {
        Object[] resourceToUpdate = null;
        synchronized (this) {
            resourceToUpdate = fChangedResources.toArray();
            fChangedResources.clear();
        }
        if (resourceToUpdate.length > 0) {
            LabelProviderChangedEvent event = new LabelProviderChangedEvent(this, resourceToUpdate);
            fireLabelProviderChanged(event);
        }
    }

    /* (non-Javadoc)
     * @see org.eclipse.jface.viewers.IBaseLabelProvider#dispose()
     */
    public void dispose() {
        fColor.dispose();
        FileBuffers.getTextFileBufferManager().removeFileBufferListener(fListener);
    }

}