viewfactory.java

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/*
*  Copyright (c) 2001 Sun Microsystems, Inc.  All rights
*  reserved.
*
*  Redistribution and use in source and binary forms, with or withouta
*  modification, are permitted provided that the following conditions
*  are met:
*
*  1. Redistributions of source code must retain the above copyright
*  notice, this list of conditions and the following disclaimer.
*
*  2. Redistributions in binary form must reproduce the above copyright
*  notice, this list of conditions and the following discalimer in
*  the documentation and/or other materials provided with the
*  distribution.
*
*  3. The end-user documentation included with the redistribution,
*  if any, must include the following acknowledgment:
*  "This product includes software developed by the
*  Sun Microsystems, Inc. for Project JXTA."
*  Alternately, this acknowledgment may appear in the software itself,
*  if and wherever such third-party acknowledgments normally appear.
*
*  4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA"
*  must not be used to endorse or promote products derived from this
*  software without prior written permission. For written
*  permission, please contact Project JXTA at http://www.jxta.org.
*
*  5. Products derived from this software may not be called "JXTA",
*  nor may "JXTA" appear in their name, without prior written
*  permission of Sun.
*
*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
*  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
*  OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
*  DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
*  ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
*  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
*  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
*  USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
*  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
*  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
*  OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
*  SUCH DAMAGE.
*  ====================================================================
*
*  This software consists of voluntary contributions made by many
*  individuals on behalf of Project JXTA.  For more
*  information on Project JXTA, please see
*  <http://www.jxta.org/>.
*
*  This license is based on the BSD license adopted by the Apache Foundation.
*
*  $Id: ViewFactory.java,v 1.3 2006/07/17 19:21:58 nano Exp $
*/

package net.jxta.myjxta;

import net.jxta.myjxta.ui.SwingViewer;

/**
 *
 * @version $Id: ViewFactory.java,v 1.3 2006/07/17 19:21:58 nano Exp $
 *
 * @author james todd [gonzo at jxta dot org]
 * @author paul trevithick
 */

public class ViewFactory {

    private static Class viewerClass = SwingViewer.class;
    private static Viewer viewer = null;
    
    public static void setViewerClass(Class v) {
        if (v != null &&
            Viewer.class.isAssignableFrom(v)) {
            viewerClass = v;
        }
    }

    public static View getView(MyJXTA myjxta) {
        if (viewer == null) {
            viewer = getViewer();
        }
        
        return viewer != null ? viewer.getView(myjxta) : null;
    }
    
    private static Viewer getViewer() {
        if (viewer == null) {
            try {
                viewer = (Viewer)viewerClass.newInstance();
            } catch (InstantiationException ie) {
                ie.printStackTrace();
            } catch (IllegalAccessException iae) {
                iae.printStackTrace();
            }
        }

        return viewer;
    }
}