ldapstudio-valueeditors/src/main/java/org/apache/directory/ldapstudio/valueeditors/ValueEditorsActivator.java

package org.apache.directory.ldapstudio.valueeditors;


import java.net.URL;

import org.eclipse.core.runtime.FileLocator;
import org.eclipse.core.runtime.Path;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.swt.graphics.Image;
import org.eclipse.ui.plugin.AbstractUIPlugin;
import org.osgi.framework.BundleContext;


/**
 * The activator class controls the plug-in life cycle
 */
public class ValueEditorsActivator extends AbstractUIPlugin
{

    /** The plug-in ID */
    public static final String PLUGIN_ID = "org.apache.directory.ldapstudio.valueeditors";

    /** The shared instance */
    private static ValueEditorsActivator plugin;


    /**
     * The constructor
     */
    public ValueEditorsActivator()
    {
        plugin = this;
    }


    /**
     * {@inheritDoc} 
     */
    public void start( BundleContext context ) throws Exception
    {
        super.start( context );
    }


    /**
     * {@inheritDoc} 
     */
    public void stop( BundleContext context ) throws Exception
    {
        plugin = null;
        super.stop( context );
    }


    /**
     * Returns the shared instance
     *
     * @return the shared instance
     */
    public static ValueEditorsActivator getDefault()
    {
        return plugin;
    }


    /**
     * Use this method to get SWT images. Use the IMG_ constants from
     * ValueEditorConstants for the key.
     * 
     * @param key
     *                The key (relative path to the image im filesystem)
     * @return The image discriptor or null
     */
    public ImageDescriptor getImageDescriptor( String key )
    {
        if ( key != null )
        {
            URL url = FileLocator.find( getBundle(), new Path( key ), null );
            if ( url != null )
                return ImageDescriptor.createFromURL( url );
            else
                return null;
        }
        else
        {
            return null;
        }
    }


    /**
     * Use this method to get SWT images. Use the IMG_ constants from
     * ValueEditorConstants for the key. A ImageRegistry is used to manage the
     * the key->Image mapping.
     * <p>
     * Note: Don't dispose the returned SWT Image. It is disposed
     * automatically when the plugin is stopped.
     * 
     * @param key
     *                The key (relative path to the image im filesystem)
     * @return The SWT Image or null
     * @see ValueEditorsConstants
     */
    public Image getImage( String key )
    {
        Image image = getImageRegistry().get( key );
        if ( image == null )
        {
            ImageDescriptor id = getImageDescriptor( key );
            if ( id != null )
            {
                image = id.createImage();
                getImageRegistry().put( key, image );
            }
        }
        return image;
    }
    
}