src/main/java/org/sikuli/slides/api/slideshow/FileDrop.java
private boolean isDragOk( final java.io.PrintStream out, final java.awt.dnd.DropTargetDragEvent evt )
    {   boolean ok = false;
        
        // Get data flavors being dragged
        java.awt.datatransfer.DataFlavor[] flavors = evt.getCurrentDataFlavors();
        
        // See if any of the flavors are a file list
        int i = 0;
        while( !ok && i < flavors.length )
        {   
            // BEGIN 2007-09-12 Nathan Blomquist -- Linux (KDE/Gnome) support added.
            // Is the flavor a file list?
            final DataFlavor curFlavor = flavors[i];
            if( curFlavor.equals( java.awt.datatransfer.DataFlavor.javaFileListFlavor ) ||
                curFlavor.isRepresentationClassReader()){
                ok = true;
            }
            // END 2007-09-12 Nathan Blomquist -- Linux (KDE/Gnome) support added.
            i++;
        }   // end while: through flavors
        
        // If logging is enabled, show data flavors
        if( out != null )
        {   if( flavors.length == 0 )
                log( out, "FileDrop: no data flavors." );
            for( i = 0; i < flavors.length; i++ )
                log( out, flavors[i].toString() );
        }   // end if: logging enabled
        
        return ok;
    }   // end isDragOk
    
    
    /** Outputs <tt>message</tt> to <tt>out</tt> if it's not null. */
    private static void log( java.io.PrintStream out, String message )
    {   // Log message if requested
        if( out != null )
            out.println( message );
    }   // end log

    
    
    
    /**
     * Removes the drag-and-drop hooks from the component and optionally
     * from the all children. You should call this if you add and remove
     * components after you've set up the drag-and-drop.
     * This will recursively unregister all components contained within
     * <var>c</var> if <var>c</var> is a {@link java.awt.Container}.
     *
     * @param c The component to unregister as a drop target
     * @since 1.0
     */
    public static boolean remove( java.awt.Component c)
    {   return remove( null, c, true );
    }   // end remove
    
    
    
    /**
     * Removes the drag-and-drop hooks from the component and optionally
     * from the all children. You should call this if you add and remove
     * components after you've set up the drag-and-drop.
     *
     * @param out Optional {@link java.io.PrintStream} for logging drag and drop messages
     * @param c The component to unregister
     * @param recursive Recursively unregister components within a container
     * @since 1.0
     */
    public static boolean remove( java.io.PrintStream out, java.awt.Component c, boolean recursive )
    {   // Make sure we support dnd.
        if( supportsDnD() )
        {   log( out, "FileDrop: Removing drag-and-drop hooks." );
            c.setDropTarget( null );
            if( recursive && ( c instanceof java.awt.Container ) )
            {   java.awt.Component[] comps = ((java.awt.Container)c).getComponents();
                for( int i = 0; i < comps.length; i++ )
                    remove( out, comps[i], recursive );
                return true;
            }   // end if: recursive
            else return false;
        }   // end if: supports DnD
        else return false;
    }   // end remove
    
    

    
/* ********  I N N E R   I N T E R F A C E   L I S T E N E R  ******** */    
    
    
    /**
     * Implement this inner interface to listen for when files are dropped. For example
     * your class declaration may begin like this:
     * <code><pre>
     *      public class MyClass implements FileDrop.Listener
     *      ...
     *      public void filesDropped( java.io.File[] files )
     *      {
     *          ...
     *      }   // end filesDropped
     *      ...
     * </pre></code>
     *
     * @since 1.1
     */
    public static interface Listener {
       
        /**
         * This method is called when files have been successfully dropped.
         *
         * @param files An array of <tt>File</tt>s that were dropped.
         * @since 1.0
         */
        public abstract void filesDropped( java.io.File[] files );
        
        
    }   // end inner-interface Listener
    
    
/* ********  I N N E R   C L A S S  ******** */    
    
    
    /**
     * This is the event that is passed to the
     * {@link FileDropListener#filesDropped filesDropped(...)} method in
     * your {@link FileDropListener} when files are dropped onto
     * a registered drop target.
     *
     * <p>I'm releasing this code into the Public Domain. Enjoy.</p>
     * 
     * @author  Robert Harder
     * @author  rob@iharder.net
     * @version 1.2
     */
    public static class Event extends java.util.EventObject {

        private java.io.File[] files;

        /**
         * Constructs an {@link Event} with the array
         * of files that were dropped and the
         * {@link FileDrop} that initiated the event.
         *
         * @param files The array of files that were dropped
         * @source The event source
         * @since 1.1
         */
        public Event( java.io.File[] files, Object source ) {
            super( source );
            this.files = files;
        }   // end constructor

        /**
         * Returns an array of files that were dropped on a
         * registered drop target.
         *
         * @return array of files that were dropped
         * @since 1.1
         */
        public java.io.File[] getFiles() {
            return files;
        }   // end getFiles
    
    }   // end inner class Event
    
    
    
/* ********  I N N E R   C L A S S  ******** */
    

    /**
     * At last an easy way to encapsulate your custom objects for dragging and dropping
     * in your Java programs!
     * When you need to create a {@link java.awt.datatransfer.Transferable} object,
     * use this class to wrap your object.
     * For example:
     * <pre><code>
     *      ...
     *      MyCoolClass myObj = new MyCoolClass();
     *      Transferable xfer = new TransferableObject( myObj );
     *      ...
     * </code></pre>
     * Or if you need to know when the data was actually dropped, like when you're
     * moving data out of a list, say, you can use the {@link TransferableObject.Fetcher}
     * inner class to return your object Just in Time.
     * For example:
     * <pre><code>
     *      ...
     *      final MyCoolClass myObj = new MyCoolClass();
     *
     *      TransferableObject.Fetcher fetcher = new TransferableObject.Fetcher()
     *      {   public Object getObject(){ return myObj; }
     *      }; // end fetcher
     *
     *      Transferable xfer = new TransferableObject( fetcher );
     *      ...
     * </code></pre>
     *
     * The {@link java.awt.datatransfer.DataFlavor} associated with 
     * {@link TransferableObject} has the representation class
     * <tt>net.iharder.dnd.TransferableObject.class</tt> and MIME type
     * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
     * This data flavor is accessible via the static
     * {@link #DATA_FLAVOR} property.
     *
     *
     * <p>I'm releasing this code into the Public Domain. Enjoy.</p>
     * 
     * @author  Robert Harder
     * @author  rob@iharder.net
     * @version 1.2
     */
    public static class TransferableObject implements java.awt.datatransfer.Transferable
    {
        /**
         * The MIME type for {@link #DATA_FLAVOR} is 
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @since 1.1
         */
        public final static String MIME_TYPE = "application/x-net.iharder.dnd.TransferableObject";


        /**
         * The default {@link java.awt.datatransfer.DataFlavor} for
         * {@link TransferableObject} has the representation class
         * <tt>net.iharder.dnd.TransferableObject.class</tt>
         * and the MIME type 
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @since 1.1
         */
        public final static java.awt.datatransfer.DataFlavor DATA_FLAVOR = 
            new java.awt.datatransfer.DataFlavor( FileDrop.TransferableObject.class, MIME_TYPE );


        private Fetcher fetcher;
        private Object data;

        private java.awt.datatransfer.DataFlavor customFlavor; 



        /**
         * Creates a new {@link TransferableObject} that wraps <var>data</var>.
         * Along with the {@link #DATA_FLAVOR} associated with this class,
         * this creates a custom data flavor with a representation class 
         * determined from <code>data.getClass()</code> and the MIME type
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @param data The data to transfer
         * @since 1.1
         */
        public TransferableObject( Object data )
        {   this.data = data;
            this.customFlavor = new java.awt.datatransfer.DataFlavor( data.getClass(), MIME_TYPE );
        }   // end constructor



        /**
         * Creates a new {@link TransferableObject} that will return the
         * object that is returned by <var>fetcher</var>.
         * No custom data flavor is set other than the default
         * {@link #DATA_FLAVOR}.
         *
         * @see Fetcher
         * @param fetcher The {@link Fetcher} that will return the data object
         * @since 1.1
         */
        public TransferableObject( Fetcher fetcher )
        {   this.fetcher = fetcher;
        }   // end constructor



        /**
         * Creates a new {@link TransferableObject} that will return the
         * object that is returned by <var>fetcher</var>.
         * Along with the {@link #DATA_FLAVOR} associated with this class,
         * this creates a custom data flavor with a representation class <var>dataClass</var>
         * and the MIME type
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @see Fetcher
         * @param dataClass The {@link java.lang.Class} to use in the custom data flavor
         * @param fetcher The {@link Fetcher} that will return the data object
         * @since 1.1
         */
        public TransferableObject( Class dataClass, Fetcher fetcher )
        {   this.fetcher = fetcher;
            this.customFlavor = new java.awt.datatransfer.DataFlavor( dataClass, MIME_TYPE );
        }   // end constructor

        /**
         * Returns the custom {@link java.awt.datatransfer.DataFlavor} associated
         * with the encapsulated object or <tt>null</tt> if the {@link Fetcher}
         * constructor was used without passing a {@link java.lang.Class}.
         *
         * @return The custom data flavor for the encapsulated object
         * @since 1.1
         */
        public java.awt.datatransfer.DataFlavor getCustomDataFlavor()
        {   return customFlavor;
        }   // end getCustomDataFlavor


    /* ********  T R A N S F E R A B L E   M E T H O D S  ******** */    


        /**
         * Returns a two- or three-element array containing first
         * the custom data flavor, if one was created in the constructors,
         * second the default {@link #DATA_FLAVOR} associated with
         * {@link TransferableObject}, and third the
         * {@link java.awt.datatransfer.DataFlavor.stringFlavor}.
         *
         * @return An array of supported data flavors
         * @since 1.1
         */
        public java.awt.datatransfer.DataFlavor[] getTransferDataFlavors() 
        {   
            if( customFlavor != null )
                return new java.awt.datatransfer.DataFlavor[]
                {   customFlavor,
                    DATA_FLAVOR,
                    java.awt.datatransfer.DataFlavor.stringFlavor
                };  // end flavors array
            else
                return new java.awt.datatransfer.DataFlavor[]
                {   DATA_FLAVOR,
                    java.awt.datatransfer.DataFlavor.stringFlavor
                };  // end flavors array
        }   // end getTransferDataFlavors



        /**
         * Returns the data encapsulated in this {@link TransferableObject}.
         * If the {@link Fetcher} constructor was used, then this is when
         * the {@link Fetcher#getObject getObject()} method will be called.
         * If the requested data flavor is not supported, then the
         * {@link Fetcher#getObject getObject()} method will not be called.
         *
         * @param flavor The data flavor for the data to return
         * @return The dropped data
         * @since 1.1
         */
        public Object getTransferData( java.awt.datatransfer.DataFlavor flavor )
        throws java.awt.datatransfer.UnsupportedFlavorException, java.io.IOException 
        {   
            // Native object
            if( flavor.equals( DATA_FLAVOR ) )
                return fetcher == null ? data : fetcher.getObject();

            // String
            if( flavor.equals( java.awt.datatransfer.DataFlavor.stringFlavor ) )
                return fetcher == null ? data.toString() : fetcher.getObject().toString();

            // We can't do anything else
            throw new java.awt.datatransfer.UnsupportedFlavorException(flavor);
        }   // end getTransferData




        /**
         * Returns <tt>true</tt> if <var>flavor</var> is one of the supported
         * flavors. Flavors are supported using the <code>equals(...)</code> method.
         *
         * @param flavor The data flavor to check
         * @return Whether or not the flavor is supported
         * @since 1.1
         */
        public boolean isDataFlavorSupported( java.awt.datatransfer.DataFlavor flavor ) 
        {
            // Native object
            if( flavor.equals( DATA_FLAVOR ) )
                return true;

            // String
            if( flavor.equals( java.awt.datatransfer.DataFlavor.stringFlavor ) )
                return true;

            // We can't do anything else
            return false;
        }   // end isDataFlavorSupported


    /* ********  I N N E R   I N T E R F A C E   F E T C H E R  ******** */    

        /**
         * Instead of passing your data directly to the {@link TransferableObject}
         * constructor, you may want to know exactly when your data was received
         * in case you need to remove it from its source (or do anyting else to it).
         * When the {@link #getTransferData getTransferData(...)} method is called
         * on the {@link TransferableObject}, the {@link Fetcher}'s
         * {@link #getObject getObject()} method will be called.
         *
         * @author Robert Harder
         * @copyright 2001
         * @version 1.1
         * @since 1.1
         */
        public static interface Fetcher
        {
            /**
             * Return the object being encapsulated in the
             * {@link TransferableObject}.
             *
             * @return The dropped object
             * @since 1.1
             */
            public abstract Object getObject();
        }   // end inner interface Fetcher



    }   // end class TransferableObject

    
    
    
    
}
private boolean isDragOk( final java.io.PrintStream out, final java.awt.dnd.DropTargetDragEvent evt )
    {   boolean ok = false;
        
        // Get data flavors being dragged
        java.awt.datatransfer.DataFlavor[] flavors = evt.getCurrentDataFlavors();
        
        // See if any of the flavors are a file list
        int i = 0;
        while( !ok && i < flavors.length )
        {   
            // BEGIN 2007-09-12 Nathan Blomquist -- Linux (KDE/Gnome) support added.
            // Is the flavor a file list?
            final DataFlavor curFlavor = flavors[i];
            if( curFlavor.equals( java.awt.datatransfer.DataFlavor.javaFileListFlavor ) ||
                curFlavor.isRepresentationClassReader()){
                ok = true;
            }
            // END 2007-09-12 Nathan Blomquist -- Linux (KDE/Gnome) support added.
            i++;
        }   // end while: through flavors
        
        // If logging is enabled, show data flavors
        if( out != null )
        {   if( flavors.length == 0 )
                log( out, "FileDrop: no data flavors." );
            for( i = 0; i < flavors.length; i++ )
                log( out, flavors[i].toString() );
        }   // end if: logging enabled
        
        return ok;
    }   // end isDragOk
    
    
    /** Outputs <tt>message</tt> to <tt>out</tt> if it's not null. */
    private static void log( java.io.PrintStream out, String message )
    {   // Log message if requested
        if( out != null )
            out.println( message );
    }   // end log

    
    
    
    /**
     * Removes the drag-and-drop hooks from the component and optionally
     * from the all children. You should call this if you add and remove
     * components after you've set up the drag-and-drop.
     * This will recursively unregister all components contained within
     * <var>c</var> if <var>c</var> is a {@link java.awt.Container}.
     *
     * @param c The component to unregister as a drop target
     * @since 1.0
     */
    public static boolean remove( java.awt.Component c)
    {   return remove( null, c, true );
    }   // end remove
    
    
    
    /**
     * Removes the drag-and-drop hooks from the component and optionally
     * from the all children. You should call this if you add and remove
     * components after you've set up the drag-and-drop.
     *
     * @param out Optional {@link java.io.PrintStream} for logging drag and drop messages
     * @param c The component to unregister
     * @param recursive Recursively unregister components within a container
     * @since 1.0
     */
    public static boolean remove( java.io.PrintStream out, java.awt.Component c, boolean recursive )
    {   // Make sure we support dnd.
        if( supportsDnD() )
        {   log( out, "FileDrop: Removing drag-and-drop hooks." );
            c.setDropTarget( null );
            if( recursive && ( c instanceof java.awt.Container ) )
            {   java.awt.Component[] comps = ((java.awt.Container)c).getComponents();
                for( int i = 0; i < comps.length; i++ )
                    remove( out, comps[i], recursive );
                return true;
            }   // end if: recursive
            else return false;
        }   // end if: supports DnD
        else return false;
    }   // end remove
    
    

    
/* ********  I N N E R   I N T E R F A C E   L I S T E N E R  ******** */    
    
    
    /**
     * Implement this inner interface to listen for when files are dropped. For example
     * your class declaration may begin like this:
     * <code><pre>
     *      public class MyClass implements FileDrop.Listener
     *      ...
     *      public void filesDropped( java.io.File[] files )
     *      {
     *          ...
     *      }   // end filesDropped
     *      ...
     * </pre></code>
     *
     * @since 1.1
     */
    public static interface Listener {
       
        /**
         * This method is called when files have been successfully dropped.
         *
         * @param files An array of <tt>File</tt>s that were dropped.
         * @since 1.0
         */
        public abstract void filesDropped( java.io.File[] files );
        
        
    }   // end inner-interface Listener
    
    
/* ********  I N N E R   C L A S S  ******** */    
    
    
    /**
     * This is the event that is passed to the
     * {@link FileDropListener#filesDropped filesDropped(...)} method in
     * your {@link FileDropListener} when files are dropped onto
     * a registered drop target.
     *
     * <p>I'm releasing this code into the Public Domain. Enjoy.</p>
     * 
     * @author  Robert Harder
     * @author  rob@iharder.net
     * @version 1.2
     */
    public static class Event extends java.util.EventObject {

        private java.io.File[] files;

        /**
         * Constructs an {@link Event} with the array
         * of files that were dropped and the
         * {@link FileDrop} that initiated the event.
         *
         * @param files The array of files that were dropped
         * @source The event source
         * @since 1.1
         */
        public Event( java.io.File[] files, Object source ) {
            super( source );
            this.files = files;
        }   // end constructor

        /**
         * Returns an array of files that were dropped on a
         * registered drop target.
         *
         * @return array of files that were dropped
         * @since 1.1
         */
        public java.io.File[] getFiles() {
            return files;
        }   // end getFiles
    
    }   // end inner class Event
    
    
    
/* ********  I N N E R   C L A S S  ******** */
    

    /**
     * At last an easy way to encapsulate your custom objects for dragging and dropping
     * in your Java programs!
     * When you need to create a {@link java.awt.datatransfer.Transferable} object,
     * use this class to wrap your object.
     * For example:
     * <pre><code>
     *      ...
     *      MyCoolClass myObj = new MyCoolClass();
     *      Transferable xfer = new TransferableObject( myObj );
     *      ...
     * </code></pre>
     * Or if you need to know when the data was actually dropped, like when you're
     * moving data out of a list, say, you can use the {@link TransferableObject.Fetcher}
     * inner class to return your object Just in Time.
     * For example:
     * <pre><code>
     *      ...
     *      final MyCoolClass myObj = new MyCoolClass();
     *
     *      TransferableObject.Fetcher fetcher = new TransferableObject.Fetcher()
     *      {   public Object getObject(){ return myObj; }
     *      }; // end fetcher
     *
     *      Transferable xfer = new TransferableObject( fetcher );
     *      ...
     * </code></pre>
     *
     * The {@link java.awt.datatransfer.DataFlavor} associated with 
     * {@link TransferableObject} has the representation class
     * <tt>net.iharder.dnd.TransferableObject.class</tt> and MIME type
     * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
     * This data flavor is accessible via the static
     * {@link #DATA_FLAVOR} property.
     *
     *
     * <p>I'm releasing this code into the Public Domain. Enjoy.</p>
     * 
     * @author  Robert Harder
     * @author  rob@iharder.net
     * @version 1.2
     */
    public static class TransferableObject implements java.awt.datatransfer.Transferable
    {
        /**
         * The MIME type for {@link #DATA_FLAVOR} is 
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @since 1.1
         */
        public final static String MIME_TYPE = "application/x-net.iharder.dnd.TransferableObject";


        /**
         * The default {@link java.awt.datatransfer.DataFlavor} for
         * {@link TransferableObject} has the representation class
         * <tt>net.iharder.dnd.TransferableObject.class</tt>
         * and the MIME type 
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @since 1.1
         */
        public final static java.awt.datatransfer.DataFlavor DATA_FLAVOR = 
            new java.awt.datatransfer.DataFlavor( FileDrop.TransferableObject.class, MIME_TYPE );


        private Fetcher fetcher;
        private Object data;

        private java.awt.datatransfer.DataFlavor customFlavor; 



        /**
         * Creates a new {@link TransferableObject} that wraps <var>data</var>.
         * Along with the {@link #DATA_FLAVOR} associated with this class,
         * this creates a custom data flavor with a representation class 
         * determined from <code>data.getClass()</code> and the MIME type
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @param data The data to transfer
         * @since 1.1
         */
        public TransferableObject( Object data )
        {   this.data = data;
            this.customFlavor = new java.awt.datatransfer.DataFlavor( data.getClass(), MIME_TYPE );
        }   // end constructor



        /**
         * Creates a new {@link TransferableObject} that will return the
         * object that is returned by <var>fetcher</var>.
         * No custom data flavor is set other than the default
         * {@link #DATA_FLAVOR}.
         *
         * @see Fetcher
         * @param fetcher The {@link Fetcher} that will return the data object
         * @since 1.1
         */
        public TransferableObject( Fetcher fetcher )
        {   this.fetcher = fetcher;
        }   // end constructor



        /**
         * Creates a new {@link TransferableObject} that will return the
         * object that is returned by <var>fetcher</var>.
         * Along with the {@link #DATA_FLAVOR} associated with this class,
         * this creates a custom data flavor with a representation class <var>dataClass</var>
         * and the MIME type
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @see Fetcher
         * @param dataClass The {@link java.lang.Class} to use in the custom data flavor
         * @param fetcher The {@link Fetcher} that will return the data object
         * @since 1.1
         */
        public TransferableObject( Class dataClass, Fetcher fetcher )
        {   this.fetcher = fetcher;
            this.customFlavor = new java.awt.datatransfer.DataFlavor( dataClass, MIME_TYPE );
        }   // end constructor

        /**
         * Returns the custom {@link java.awt.datatransfer.DataFlavor} associated
         * with the encapsulated object or <tt>null</tt> if the {@link Fetcher}
         * constructor was used without passing a {@link java.lang.Class}.
         *
         * @return The custom data flavor for the encapsulated object
         * @since 1.1
         */
        public java.awt.datatransfer.DataFlavor getCustomDataFlavor()
        {   return customFlavor;
        }   // end getCustomDataFlavor


    /* ********  T R A N S F E R A B L E   M E T H O D S  ******** */    


        /**
         * Returns a two- or three-element array containing first
         * the custom data flavor, if one was created in the constructors,
         * second the default {@link #DATA_FLAVOR} associated with
         * {@link TransferableObject}, and third the
         * {@link java.awt.datatransfer.DataFlavor.stringFlavor}.
         *
         * @return An array of supported data flavors
         * @since 1.1
         */
        public java.awt.datatransfer.DataFlavor[] getTransferDataFlavors() 
        {   
            if( customFlavor != null )
                return new java.awt.datatransfer.DataFlavor[]
                {   customFlavor,
                    DATA_FLAVOR,
                    java.awt.datatransfer.DataFlavor.stringFlavor
                };  // end flavors array
            else
                return new java.awt.datatransfer.DataFlavor[]
                {   DATA_FLAVOR,
                    java.awt.datatransfer.DataFlavor.stringFlavor
                };  // end flavors array
        }   // end getTransferDataFlavors



        /**
         * Returns the data encapsulated in this {@link TransferableObject}.
         * If the {@link Fetcher} constructor was used, then this is when
         * the {@link Fetcher#getObject getObject()} method will be called.
         * If the requested data flavor is not supported, then the
         * {@link Fetcher#getObject getObject()} method will not be called.
         *
         * @param flavor The data flavor for the data to return
         * @return The dropped data
         * @since 1.1
         */
        public Object getTransferData( java.awt.datatransfer.DataFlavor flavor )
        throws java.awt.datatransfer.UnsupportedFlavorException, java.io.IOException 
        {   
            // Native object
            if( flavor.equals( DATA_FLAVOR ) )
                return fetcher == null ? data : fetcher.getObject();

            // String
            if( flavor.equals( java.awt.datatransfer.DataFlavor.stringFlavor ) )
                return fetcher == null ? data.toString() : fetcher.getObject().toString();

            // We can't do anything else
            throw new java.awt.datatransfer.UnsupportedFlavorException(flavor);
        }   // end getTransferData




        /**
         * Returns <tt>true</tt> if <var>flavor</var> is one of the supported
         * flavors. Flavors are supported using the <code>equals(...)</code> method.
         *
         * @param flavor The data flavor to check
         * @return Whether or not the flavor is supported
         * @since 1.1
         */
        public boolean isDataFlavorSupported( java.awt.datatransfer.DataFlavor flavor ) 
        {
            // Native object
            if( flavor.equals( DATA_FLAVOR ) )
                return true;

            // String
            if( flavor.equals( java.awt.datatransfer.DataFlavor.stringFlavor ) )
                return true;

            // We can't do anything else
            return false;
        }   // end isDataFlavorSupported


    /* ********  I N N E R   I N T E R F A C E   F E T C H E R  ******** */    

        /**
         * Instead of passing your data directly to the {@link TransferableObject}
         * constructor, you may want to know exactly when your data was received
         * in case you need to remove it from its source (or do anyting else to it).
         * When the {@link #getTransferData getTransferData(...)} method is called
         * on the {@link TransferableObject}, the {@link Fetcher}'s
         * {@link #getObject getObject()} method will be called.
         *
         * @author Robert Harder
         * @copyright 2001
         * @version 1.1
         * @since 1.1
         */
        public static interface Fetcher
        {
            /**
             * Return the object being encapsulated in the
             * {@link TransferableObject}.
             *
             * @return The dropped object
             * @since 1.1
             */
            public abstract Object getObject();
        }   // end inner interface Fetcher



    }   // end class TransferableObject

    
    
    
    
}
private boolean isDragOk ( final java . io . PrintStream out , final java . awt . dnd . DropTargetDragEvent evt ) { boolean ok = false ; // Get data flavors being dragged
 java . awt . datatransfer . DataFlavor [ ] flavors = evt . getCurrentDataFlavors ( ) ; // See if any of the flavors are a file list
 int i = 0 ; while ( ! ok && i < flavors . length ) { // BEGIN 2007-09-12 Nathan Blomquist -- Linux (KDE/Gnome) support added.
 // Is the flavor a file list?
 final DataFlavor curFlavor = flavors [ i ] ; if ( curFlavor . equals ( java . awt . datatransfer . DataFlavor . javaFileListFlavor ) || curFlavor . isRepresentationClassReader ( ) ) { ok = true ; } // END 2007-09-12 Nathan Blomquist -- Linux (KDE/Gnome) support added.
 i ++ ; } // end while: through flavors
 // If logging is enabled, show data flavors
 if ( out != null ) { if ( flavors . length == 0 ) log ( out , "FileDrop: no data flavors." ) ; for ( i = 0 ; i < flavors . length ; i ++ ) log ( out , flavors [ i ] . toString ( ) ) ; } // end if: logging enabled
 return ok ; } // end isDragOk
 /** Outputs <tt>message</tt> to <tt>out</tt> if it's not null. */ private static void log ( java . io . PrintStream out , String message ) { // Log message if requested
 if ( out != null ) out . println ( message ) ; } // end log
 /**
     * Removes the drag-and-drop hooks from the component and optionally
     * from the all children. You should call this if you add and remove
     * components after you've set up the drag-and-drop.
     * This will recursively unregister all components contained within
     * <var>c</var> if <var>c</var> is a {@link java.awt.Container}.
     *
     * @param c The component to unregister as a drop target
     * @since 1.0
     */ public static boolean remove ( java . awt . Component c ) { return remove ( null , c , true ) ; } // end remove
 /**
     * Removes the drag-and-drop hooks from the component and optionally
     * from the all children. You should call this if you add and remove
     * components after you've set up the drag-and-drop.
     *
     * @param out Optional {@link java.io.PrintStream} for logging drag and drop messages
     * @param c The component to unregister
     * @param recursive Recursively unregister components within a container
     * @since 1.0
     */ public static boolean remove ( java . io . PrintStream out , java . awt . Component c , boolean recursive ) { // Make sure we support dnd.
 if ( supportsDnD ( ) ) { log ( out , "FileDrop: Removing drag-and-drop hooks." ) ; c . setDropTarget ( null ) ; if ( recursive && ( c instanceof java . awt . Container ) ) { java . awt . Component [ ] comps = ( ( java . awt . Container ) c ) . getComponents ( ) ; for ( int i = 0 ; i < comps . length ; i ++ ) remove ( out , comps [ i ] , recursive ) ; return true ; } // end if: recursive
 else return false ; } // end if: supports DnD
 else return false ; } // end remove
 /* ********  I N N E R   I N T E R F A C E   L I S T E N E R  ******** */ /**
     * Implement this inner interface to listen for when files are dropped. For example
     * your class declaration may begin like this:
     * <code><pre>
     *      public class MyClass implements FileDrop.Listener
     *      ...
     *      public void filesDropped( java.io.File[] files )
     *      {
     *          ...
     *      }   // end filesDropped
     *      ...
     * </pre></code>
     *
     * @since 1.1
     */ public static interface Listener { /**
         * This method is called when files have been successfully dropped.
         *
         * @param files An array of <tt>File</tt>s that were dropped.
         * @since 1.0
         */ public abstract void filesDropped ( java . io . File [ ] files ) ; } // end inner-interface Listener
 /* ********  I N N E R   C L A S S  ******** */ /**
     * This is the event that is passed to the
     * {@link FileDropListener#filesDropped filesDropped(...)} method in
     * your {@link FileDropListener} when files are dropped onto
     * a registered drop target.
     *
     * <p>I'm releasing this code into the Public Domain. Enjoy.</p>
     * 
     * @author  Robert Harder
     * @author  rob@iharder.net
     * @version 1.2
     */ public static class Event extends java . util . EventObject { private java . io . File [ ] files ; /**
         * Constructs an {@link Event} with the array
         * of files that were dropped and the
         * {@link FileDrop} that initiated the event.
         *
         * @param files The array of files that were dropped
         * @source The event source
         * @since 1.1
         */ public Event ( java . io . File [ ] files , Object source ) { super ( source ) ; this . files = files ; } // end constructor
 /**
         * Returns an array of files that were dropped on a
         * registered drop target.
         *
         * @return array of files that were dropped
         * @since 1.1
         */ public java . io . File [ ] getFiles ( ) { return files ; } // end getFiles
 } // end inner class Event
 /* ********  I N N E R   C L A S S  ******** */ /**
     * At last an easy way to encapsulate your custom objects for dragging and dropping
     * in your Java programs!
     * When you need to create a {@link java.awt.datatransfer.Transferable} object,
     * use this class to wrap your object.
     * For example:
     * <pre><code>
     *      ...
     *      MyCoolClass myObj = new MyCoolClass();
     *      Transferable xfer = new TransferableObject( myObj );
     *      ...
     * </code></pre>
     * Or if you need to know when the data was actually dropped, like when you're
     * moving data out of a list, say, you can use the {@link TransferableObject.Fetcher}
     * inner class to return your object Just in Time.
     * For example:
     * <pre><code>
     *      ...
     *      final MyCoolClass myObj = new MyCoolClass();
     *
     *      TransferableObject.Fetcher fetcher = new TransferableObject.Fetcher()
     *      {   public Object getObject(){ return myObj; }
     *      }; // end fetcher
     *
     *      Transferable xfer = new TransferableObject( fetcher );
     *      ...
     * </code></pre>
     *
     * The {@link java.awt.datatransfer.DataFlavor} associated with 
     * {@link TransferableObject} has the representation class
     * <tt>net.iharder.dnd.TransferableObject.class</tt> and MIME type
     * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
     * This data flavor is accessible via the static
     * {@link #DATA_FLAVOR} property.
     *
     *
     * <p>I'm releasing this code into the Public Domain. Enjoy.</p>
     * 
     * @author  Robert Harder
     * @author  rob@iharder.net
     * @version 1.2
     */ public static class TransferableObject implements java . awt . datatransfer . Transferable { /**
         * The MIME type for {@link #DATA_FLAVOR} is 
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @since 1.1
         */ public final static String MIME_TYPE = "application/x-net.iharder.dnd.TransferableObject" ; /**
         * The default {@link java.awt.datatransfer.DataFlavor} for
         * {@link TransferableObject} has the representation class
         * <tt>net.iharder.dnd.TransferableObject.class</tt>
         * and the MIME type 
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @since 1.1
         */ public final static java . awt . datatransfer . DataFlavor DATA_FLAVOR = new java . awt . datatransfer . DataFlavor ( FileDrop . TransferableObject . class , MIME_TYPE ) ; private Fetcher fetcher ; private Object data ; private java . awt . datatransfer . DataFlavor customFlavor ; /**
         * Creates a new {@link TransferableObject} that wraps <var>data</var>.
         * Along with the {@link #DATA_FLAVOR} associated with this class,
         * this creates a custom data flavor with a representation class 
         * determined from <code>data.getClass()</code> and the MIME type
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @param data The data to transfer
         * @since 1.1
         */ public TransferableObject ( Object data ) { this . data = data ; this . customFlavor = new java . awt . datatransfer . DataFlavor ( data . getClass ( ) , MIME_TYPE ) ; } // end constructor
 /**
         * Creates a new {@link TransferableObject} that will return the
         * object that is returned by <var>fetcher</var>.
         * No custom data flavor is set other than the default
         * {@link #DATA_FLAVOR}.
         *
         * @see Fetcher
         * @param fetcher The {@link Fetcher} that will return the data object
         * @since 1.1
         */ public TransferableObject ( Fetcher fetcher ) { this . fetcher = fetcher ; } // end constructor
 /**
         * Creates a new {@link TransferableObject} that will return the
         * object that is returned by <var>fetcher</var>.
         * Along with the {@link #DATA_FLAVOR} associated with this class,
         * this creates a custom data flavor with a representation class <var>dataClass</var>
         * and the MIME type
         * <tt>application/x-net.iharder.dnd.TransferableObject</tt>.
         *
         * @see Fetcher
         * @param dataClass The {@link java.lang.Class} to use in the custom data flavor
         * @param fetcher The {@link Fetcher} that will return the data object
         * @since 1.1
         */ public TransferableObject ( Class dataClass , Fetcher fetcher ) { this . fetcher = fetcher ; this . customFlavor = new java . awt . datatransfer . DataFlavor ( dataClass , MIME_TYPE ) ; } // end constructor
 /**
         * Returns the custom {@link java.awt.datatransfer.DataFlavor} associated
         * with the encapsulated object or <tt>null</tt> if the {@link Fetcher}
         * constructor was used without passing a {@link java.lang.Class}.
         *
         * @return The custom data flavor for the encapsulated object
         * @since 1.1
         */ public java . awt . datatransfer . DataFlavor getCustomDataFlavor ( ) { return customFlavor ; } // end getCustomDataFlavor
 /* ********  T R A N S F E R A B L E   M E T H O D S  ******** */ /**
         * Returns a two- or three-element array containing first
         * the custom data flavor, if one was created in the constructors,
         * second the default {@link #DATA_FLAVOR} associated with
         * {@link TransferableObject}, and third the
         * {@link java.awt.datatransfer.DataFlavor.stringFlavor}.
         *
         * @return An array of supported data flavors
         * @since 1.1
         */ public java . awt . datatransfer . DataFlavor [ ] getTransferDataFlavors ( ) { if ( customFlavor != null ) return new java . awt . datatransfer . DataFlavor [ ] { customFlavor , DATA_FLAVOR , java . awt . datatransfer . DataFlavor . stringFlavor } ; // end flavors array
 else return new java . awt . datatransfer . DataFlavor [ ] { DATA_FLAVOR , java . awt . datatransfer . DataFlavor . stringFlavor } ; // end flavors array
 } // end getTransferDataFlavors
 /**
         * Returns the data encapsulated in this {@link TransferableObject}.
         * If the {@link Fetcher} constructor was used, then this is when
         * the {@link Fetcher#getObject getObject()} method will be called.
         * If the requested data flavor is not supported, then the
         * {@link Fetcher#getObject getObject()} method will not be called.
         *
         * @param flavor The data flavor for the data to return
         * @return The dropped data
         * @since 1.1
         */ public Object getTransferData ( java . awt . datatransfer . DataFlavor flavor ) throws java . awt . datatransfer . UnsupportedFlavorException , java . io . IOException { // Native object
 if ( flavor . equals ( DATA_FLAVOR ) ) return fetcher == null ? data : fetcher . getObject ( ) ; // String
 if ( flavor . equals ( java . awt . datatransfer . DataFlavor . stringFlavor ) ) return fetcher == null ? data . toString ( ) : fetcher . getObject ( ) . toString ( ) ; // We can't do anything else
 throw new java . awt . datatransfer . UnsupportedFlavorException ( flavor ) ; } // end getTransferData
 /**
         * Returns <tt>true</tt> if <var>flavor</var> is one of the supported
         * flavors. Flavors are supported using the <code>equals(...)</code> method.
         *
         * @param flavor The data flavor to check
         * @return Whether or not the flavor is supported
         * @since 1.1
         */ public boolean isDataFlavorSupported ( java . awt . datatransfer . DataFlavor flavor ) { // Native object
 if ( flavor . equals ( DATA_FLAVOR ) ) return true ; // String
 if ( flavor . equals ( java . awt . datatransfer . DataFlavor . stringFlavor ) ) return true ; // We can't do anything else
 return false ; } // end isDataFlavorSupported
 /* ********  I N N E R   I N T E R F A C E   F E T C H E R  ******** */ /**
         * Instead of passing your data directly to the {@link TransferableObject}
         * constructor, you may want to know exactly when your data was received
         * in case you need to remove it from its source (or do anyting else to it).
         * When the {@link #getTransferData getTransferData(...)} method is called
         * on the {@link TransferableObject}, the {@link Fetcher}'s
         * {@link #getObject getObject()} method will be called.
         *
         * @author Robert Harder
         * @copyright 2001
         * @version 1.1
         * @since 1.1
         */ public static interface Fetcher { /**
             * Return the object being encapsulated in the
             * {@link TransferableObject}.
             *
             * @return The dropped object
             * @since 1.1
             */ public abstract Object getObject ( ) ; } // end inner interface Fetcher
 } // end class TransferableObject
 }
Determine if the dragged data is a file list.
Determine if the dragged data is a file list .