/*
 *                 Sun Public License Notice
 * 
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 * 
 * The Original Code is NetBeans. The Initial Developer of the Original
 * Code is Sun Microsystems, Inc. Portions Copyright 1997-2002 Sun
 * Microsystems, Inc. All Rights Reserved.
 */
package org.netbeans.modules.xml.editor;

import java.io.*;

import org.openide.windows.*;
import org.openide.explorer.ExplorerPanel;
import org.openide.text.*;
import org.openide.loaders.DataObject;
import org.openide.loaders.DataObjectNotFoundException;
import org.openide.cookies.OpenCookie;
import org.openide.util.io.SafeException;
import org.openide.filesystems.FileStateInvalidException;

import org.netbeans.modules.xml.core.XMLDataObjectLook;
import org.netbeans.modules.xml.tree.editor.TreeEditorSupport;
import org.netbeans.modules.xml.tree.editor.TreeEditorComponent;

/**
 * @deprecated Backward compatibility class for tree editor component.
 *
 * @author  Petr Kuzel
 * @author  Libor Kramolis
 * @version 0.2
 */
public final class XMLTopComponent extends ExplorerPanel implements Externalizable {
    /** Serial Version UID */
    private static final long serialVersionUID = -643830068955628059L;    

    /** */
    private TreeEditorSupport support = null;

    /** */
    public XMLTopComponent () {
        // externalization requires it
    }
    

    /**
     */
    private Object readResolve () throws ObjectStreamException {
        if ( support != null ) {
            return new TreeEditorComponent (support);
        } else {
            return null;
        }
    }                

    public void readExternal (ObjectInput in) throws IOException, ClassNotFoundException {
        try {
            super.readExternal (in);
            
            // see immediatelly that backward compatibility reading failed.
            setName ("FFJ 2.0 TreeEditorComponent"); // NOI18N
        
            Object obj = in.readObject();
        
            if ( ( obj instanceof XMLDataObjectLook ) &&
                 ( obj instanceof DataObject ) ) {
                
                XMLDataObjectLook doi = (XMLDataObjectLook) obj;

                if ( ((DataObject) doi).isValid() ) {
                    support = (TreeEditorSupport) doi.getCookie (OpenCookie.class);
                }
            }
        } catch (IOException ioExc) {
            Exception exc;
            if ( ioExc instanceof SafeException ) {
                exc = ((SafeException) ioExc).getException();
            } else {
                exc = ioExc;
            }
            if ( ( exc instanceof DataObjectNotFoundException ) ||
                 ( exc instanceof FileStateInvalidException ) ) {
                //!!! expected
            } else {
                throw ioExc;
            }
        }
    }
               
    /**
     */
    public void writeExternal (ObjectOutput objectOutput) throws IOException {
        throw new IOException ("This placeholder can not be written down."); // NOI18N
    }
    
}