One Model, Two Trees, Two Different Views

Question

Here is what I need to do:
- Maintain 1 and only 1 model for tree data
- Display two different JTrees, each using the same model, but one showing all the data, and the other only showing a subset.
Example:
My Tree Data model is a file system containing all drives and folders below them.
One tree needs to show all the drives and folders below them.
The other tree needs to only show one drive and the folders below it.
I am open to any suggestions, even if you are just brainstorming.

Answer 1

My abstract adapter for my experimantal GEDCOM editor - still being worked on
abstract public class AbstractTreeViewAdapter implements TreeModel
    private String rootElementName_;
    private Model m_model;
    private Element rootElement_;
    public AbstractTreeViewAdapter(Model model, String rootElementName)
        m_model = model;
        rootElementName_ = rootElementName;
        Element root = m_model.getGEDCOMDocument().getRootElement();
        rootElement_ = root.getChild(rootElementName, root.getNamespace());
        m_model.addPropertyChangeListener(new PropertyChangeListener()
            public void propertyChange(PropertyChangeEvent event)
                if (rootElement_ != null)
                    removeAllChildNodesFromRoot();
                Element root = m_model.getGEDCOMDocument().getRootElement();
                rootElement_ = root.getChild(rootElementName_, root.getNamespace());
                addAllChildNodes();
    //  Methods to edit the tree /////////////////////////////////////
    public void removeChild(Object parent, int childIndex)
    public void removeChild(Object parent, Element child)
        int childIndex = getIndexOfChild(parent, child);
        if (childIndex < 0)
            throw new IllegalArgumentException("Cannot find child");
        removeChild(parent, childIndex);
    public void insertChild(Object parent, Element child, int index)
        int numberOfChildren = getChildCount(parent);
        if ((index < 0) || (index > numberOfChildren))
            throw new IllegalArgumentException("Index out of range");
        Object[] path = getPath((Element)parent);
        Object[] childToInsert = {child};
        int[] indexToInsert = {index};
        TreeModelEvent event = new TreeModelEvent(this, path, indexToInsert, childToInsert);
        Iterator it = m_listeners.iterator();
        while (it.hasNext())
            TreeModelListener listener = (TreeModelListener)it.next();
            listener.treeNodesInserted(event);
    private Object[] getPath(Element element)
        LinkedList result = new LinkedList();
        while ((element != null) && !element.getName().equals(rootElementName_))
            result.addFirst(element);
            element = element.getParent();
        result.addFirst(getRoot());
        return result.toArray();
    public Object getChild(Object obj, int index)
        if (obj instanceof Element)
            return ((Element)obj).getChildren().get(index);
        else if (obj instanceof Model)
            return getChild(rootElement_, index);
        else
            return null;
    public int getChildCount(Object obj)
        if (obj instanceof Element)
            return ((Element)obj).getChildren().size();
        else if (obj instanceof Model)
            int childCount = (rootElement_ == null)?0:rootElement_.getChildren().size();
            return childCount;
        else
            return 0;
    public int getIndexOfChild(Object obj, Object child)
        if (obj instanceof Element)
            Iterator it = ((Element)obj).getChildren().iterator();
            for( int index = 0; it.hasNext(); index++)
                if (it.next() == child)
                    return index;
            return -1;
        else if (obj instanceof Model)
            return getIndexOfChild(rootElement_, child);
        else
            return -1;
    public Object getRoot()
        return m_model;
    public boolean isLeaf(Object obj)
        if (obj instanceof Element)
            return !((Element)obj).hasChildren();
        else if (obj instanceof Model)
            return false;
        else
            return true;
    public void removeTreeModelListener(javax.swing.event.TreeModelListener treeModelListener)
        m_listeners.remove(treeModelListener);
    public void valueForPathChanged(javax.swing.tree.TreePath treePath, Object obj)
        System.out.println("VFPC"+obj);
    public void addTreeModelListener(javax.swing.event.TreeModelListener treeModelListener)
        m_listeners.remove(treeModelListener);
        m_listeners.add(treeModelListener);
    public void removeAllChildNodesFromRoot()
        Object[] path =
        {getRoot()};
        removeAllChildNodes(path);
    public void removeAllChildNodes(Object[] path)
        ChildrenOf children = new ChildrenOf(path[path.length-1]);
        if (children.size() == 0)
            return;
        TreeModelEvent event = new TreeModelEvent(this, path, children.getIndexSet(), children.getChildren());
        Iterator it = m_listeners.iterator();
        while (it.hasNext())
            TreeModelListener listener = (TreeModelListener)it.next();
            listener.treeNodesRemoved(event);
    public void addAllChildNodes()
        Object[] path =
        {getRoot()};
        addAllChildNodes(path);
    public void addAllChildNodes(Object[] path)
        ChildrenOf children = new ChildrenOf(path[path.length-1]);
        if (children.size() == 0)
            return;
        TreeModelEvent event = new TreeModelEvent(this, path, children.getIndexSet(), children.getChildren());
        Iterator it = m_listeners.iterator();
        while (it.hasNext())
            TreeModelListener listener = (TreeModelListener)it.next();
            listener.treeNodesInserted(event);
    private class ChildrenOf
        ChildrenOf(Object parent)
            if (parent instanceof Element)
                children_ = ((Element)parent).getChildren().toArray();
            else if (parent instanceof Model)
                if (rootElement_ == null)
                    children_ = new Object[0];
                else
                    children_ = rootElement_.getChildren().toArray();
            else
                children_ = new Object[0];
        int[] getIndexSet()
            int[] indexes = new int[children_.length];
            for (int i = 0; i < children_.length; i++)
                indexes[i] = i;
            return indexes;
        Object[] getChildren()
            return children_;
        int size()
            return children_.length;
        private Object[] children_;
    public void notifyAllChanged(TreeModelEvent event)
        Iterator it = m_listeners.iterator();
        while (it.hasNext())
            TreeModelListener listener = (TreeModelListener)it.next();
            listener.treeStructureChanged(event);
    public void notifyStructureChanged(TreeModelEvent event)
        Iterator it = m_listeners.iterator();
        while (it.hasNext())
            TreeModelListener listener = (TreeModelListener)it.next();
            listener.treeStructureChanged(event);
     * The set of listeners that will be notifed when the tree changes
    private Vector m_listeners = new Vector();
}