bundles/org.eclipse.rap.addons.filedialog/src/org/eclipse/swt/widgets/FileDialog.java - rap/incubator/org.eclipse.rap.incubator.fileupload - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2014 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *    IBM Corporation - initial API and implementation
  *    Austin Riddle (Texas Center for Applied Technology) - RAP implementation
  *    EclipseSource - ongoing development
  *******************************************************************************/
 package org.eclipse.swt.widgets;

 import static org.eclipse.swt.internal.widgets.LayoutUtil.createButtonLayoutData;
 import static org.eclipse.swt.internal.widgets.LayoutUtil.createFillData;
 import static org.eclipse.swt.internal.widgets.LayoutUtil.createGridLayout;
 import static org.eclipse.swt.internal.widgets.LayoutUtil.createHorizontalFillData;

 import java.io.File;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;

 import org.eclipse.rap.addons.fileupload.DiskFileUploadReceiver;
 import org.eclipse.rap.addons.fileupload.FileUploadHandler;
 import org.eclipse.rap.rwt.client.ClientFile;
 import org.eclipse.rap.rwt.dnd.ClientFileTransfer;
 import org.eclipse.rap.rwt.service.ServerPushSession;
 import org.eclipse.rap.rwt.widgets.FileUpload;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.SWTException;
 import org.eclipse.swt.custom.ScrolledComposite;
 import org.eclipse.swt.dnd.DND;
 import org.eclipse.swt.dnd.DropTarget;
 import org.eclipse.swt.dnd.DropTargetAdapter;
 import org.eclipse.swt.dnd.DropTargetEvent;
 import org.eclipse.swt.dnd.Transfer;
 import org.eclipse.swt.events.ControlAdapter;
 import org.eclipse.swt.events.ControlEvent;
 import org.eclipse.swt.events.DisposeEvent;
 import org.eclipse.swt.events.DisposeListener;
 import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.graphics.Rectangle;
 import org.eclipse.swt.internal.widgets.FileUploadRunnable;
 import org.eclipse.swt.internal.widgets.ProgressCollector;
 import org.eclipse.swt.internal.widgets.UploadPanel;
 import org.eclipse.swt.internal.widgets.Uploader;
 import org.eclipse.swt.internal.widgets.UploaderService;
 import org.eclipse.swt.internal.widgets.UploaderWidget;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;


 /**
  * Instances of this class allow the user to navigate the file system and select
  * a file name. The selected file will be uploaded to the server and the path
  * made available as the result of the dialog.
  * <dl>
  * <dt><b>Styles:</b></dt>
  * <dd><!--SAVE, OPEN,--> MULTI</dd>
  * <dt><b>Events:</b></dt>
  * <dd>(none)</dd>
  * </dl>
  * <p>
  * The OPEN style is applied by default and setting any other styles has no
  * effect. <!--Note: Only one of the styles SAVE and OPEN may be specified.-->
  * </p>
  * <p>
  * IMPORTANT: This class is intended to be subclassed <em>only</em> within the
  * SWT implementation.
  * </p>
  *
  * @see <a href="http://www.eclipse.org/swt/snippets/#filedialog">FileDialog
  *      snippets</a>
  * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example:
  *      ControlExample, Dialog tab</a>
  * @see <a href="http://www.eclipse.org/swt/">Sample code and further
  *      information</a>
  */
 public class FileDialog extends Dialog {

   private final ServerPushSession pushSession;
   private final ThreadPoolExecutor singleThreadExecutor;
   private Display display;
   private ScrolledComposite uploadsScroller;
   private Button okButton;
   private Label spacer;
   private UploadPanel placeHolder;
   private ProgressCollector progressCollector;

   /**
    * Constructs a new instance of this class given only its parent.
    *
    * @param parent a shell which will be the parent of the new instance
    * @exception IllegalArgumentException <ul>
    *              <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
    *              </ul>
    * @exception SWTException <ul>
    *              <li>ERROR_THREAD_INVALID_ACCESS - if not called from the
    *              thread that created the parent</li>
    *              <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed
    *              subclass</li>
    *              </ul>
    */
   public FileDialog( Shell parent ) {
     this( parent, SWT.TITLE | SWT.BORDER | SWT.APPLICATION_MODAL );
   }

   /**
    * Constructs a new instance of this class given its parent and a style value
    * describing its behavior and appearance.
    * <p>
    * The style value is either one of the style constants defined in class
    * <code>SWT</code> which is applicable to instances of this class, or must be
    * built by <em>bitwise OR</em>'ing together (that is, using the
    * <code>int</code> "|" operator) two or more of those <code>SWT</code> style
    * constants. The class description lists the style constants that are
    * applicable to the class. Style bits are also inherited from superclasses.
    * </p>
    *
    * @param parent a shell which will be the parent of the new instance
    * @param style the style of dialog to construct
    * @exception IllegalArgumentException <ul>
    *              <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
    *              </ul>
    * @exception SWTException <ul>
    *              <li>ERROR_THREAD_INVALID_ACCESS - if not called from the
    *              thread that created the parent</li>
    *              <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed
    *              subclass</li>
    *              </ul>
    */
   public FileDialog( Shell parent, int style ) {
     super( parent, checkStyle( parent, style ) );
     checkSubclass();
     pushSession = new ServerPushSession();
     singleThreadExecutor = createSingleThreadExecutor();
   }

   /**
    * Returns the path of the first file that was selected in the dialog relative
    * to the filter path, or an empty string if no such file has been selected.
    *
    * @return the relative path of the file
    */
   public String getFileName() {
     String[] fileNames = getFileNames();
     return fileNames.length == 0 ? "" : fileNames[ 0 ];
   }

   /**
    * Returns a (possibly empty) array with the paths of all files that were
    * selected in the dialog relative to the filter path.
    *
    * @return the relative paths of the files
    */
   public String[] getFileNames() {
     return returnCode == SWT.OK ? progressCollector.getCompletedFileNames() : new String[ 0 ];
   }

   /**
    * Makes the dialog visible and brings it to the front
    * of the display.
    *
    * @return a string describing the absolute path of the first selected file,
    *         or null if the dialog was cancelled or an error occurred
    *
    * @exception SWTException <ul>
    *    <li>ERROR_WIDGET_DISPOSED - if the dialog has been disposed</li>
    *    <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the dialog</li>
    * </ul>
    */
   public String open() {
     prepareOpen();
     runEventLoop( shell );
     return returnCode == SWT.OK ? getFileName() : null;
   }

   @Override
   protected void prepareOpen() {
     createShell();
     createControls();
     initializeBounds();
     initializeDefaults();
     pushSession.start();
   }

   private void createShell() {
     shell = new Shell( getParent(), getStyle() );
     shell.setText( getText() );
     shell.addDisposeListener( new DisposeListener() {
       public void widgetDisposed( DisposeEvent event ) {
         cleanup();
       }
     } );
     display = shell.getDisplay();
   }

   private void initializeBounds() {
     Point prefSize = shell.computeSize( SWT.DEFAULT, SWT.DEFAULT );
     if( isMulti() ) {
       prefSize.y += 165; // ensure space for five files
     }
     shell.setMinimumSize( prefSize );
     Rectangle parentSize = getParent().getBounds();
     int locationX = ( parentSize.width - prefSize.x ) / 2 + parentSize.x;
     int locationY = ( parentSize.height - prefSize.y ) / 2 + parentSize.y;
     shell.setBounds( locationX, locationY, prefSize.x, prefSize.y );
     // set spacer real layout data after shell prefer size calculation
     spacer.setLayoutData( createHorizontalFillData() );
   }

   private void initializeDefaults() {
     setReturnCode( SWT.CANCEL );
   }

   private void createControls() {
     shell.setLayout( createGridLayout( 1, 10, 10 ) );
     createDialogArea( shell );
     createButtonsArea( shell );
   }

   private void createDialogArea( Composite parent ) {
     Composite dialogArea = new Composite( parent, SWT.NONE );
     dialogArea.setLayoutData( createFillData() );
     dialogArea.setLayout( createGridLayout( 1, 0, 5 ) );
     createUploadsArea( dialogArea );
     createProgressArea( dialogArea );
     createDropTarget( dialogArea );
   }

   private void createUploadsArea( Composite parent ) {
     uploadsScroller = new ScrolledComposite( parent, isMulti() ? SWT.V_SCROLL : SWT.NONE );
     uploadsScroller.setLayoutData( createFillData() );
     uploadsScroller.setExpandHorizontal( true );
     uploadsScroller.setExpandVertical( true );
     Composite scrolledContent = new Composite( uploadsScroller, SWT.NONE );
     scrolledContent.setLayout( new GridLayout( 1, false ) );
     uploadsScroller.setContent( scrolledContent );
     uploadsScroller.addControlListener( new ControlAdapter() {
       @Override
       public void controlResized( ControlEvent event ) {
         updateScrolledComposite();
       }
     } );
     placeHolder = new UploadPanel( scrolledContent, new String[] { "" } );
     placeHolder.setLayoutData( createHorizontalFillData() );
   }

   private void createProgressArea( Composite parent ) {
     progressCollector = new ProgressCollector( parent );
     progressCollector.setLayoutData( createHorizontalFillData() );
   }

   private void createDropTarget( Control control ) {
     DropTarget dropTarget = new DropTarget( control, DND.DROP_MOVE | DND.DROP_COPY );
     dropTarget.setTransfer( new Transfer[] { ClientFileTransfer.getInstance() } );
     dropTarget.addDropListener( new DropTargetAdapter() {
       @Override
       public void dropAccept( DropTargetEvent event ) {
         if( !ClientFileTransfer.getInstance().isSupportedType( event.currentDataType ) ) {
           event.detail = DND.DROP_NONE;
         }
       }
       @Override
       public void drop( DropTargetEvent event ) {
         handleFileDrop( ( ClientFile[] )event.data );
       }
     } );
   }

   private void handleFileDrop( ClientFile[] clientFiles ) {
     placeHolder.dispose();
     ClientFile[] files = isMulti() ? clientFiles : new ClientFile[] { clientFiles[ 0 ] };
     UploadPanel uploadPanel = createUploadPanel( getFileNames( files ) );
     updateScrolledComposite();
     Uploader uploader = new UploaderService( files );
     FileUploadHandler handler = new FileUploadHandler( new DiskFileUploadReceiver() );
     FileUploadRunnable uploadRunnable = new FileUploadRunnable( uploadPanel,
                                                                 progressCollector,
                                                                 uploader,
                                                                 handler );
     singleThreadExecutor.execute( uploadRunnable );
   }

   private static String[] getFileNames( ClientFile[] clientFiles ) {
     String[] fileNames = new String[ clientFiles.length ];
     for( int i = 0; i < fileNames.length; i++ ) {
       fileNames[ i ] = clientFiles[ i ].getName();
     }
     return fileNames;
   }

   private void createButtonsArea( Composite parent ) {
     Composite buttonsArea = new Composite( parent, SWT.NONE );
     buttonsArea.setLayout( createGridLayout( 4, 0, 5 ) );
     buttonsArea.setLayoutData( createHorizontalFillData() );
     String text = isMulti() ? SWT.getMessage( "SWT_Add" ) : SWT.getMessage( "SWT_Browse" );
     createFileUpload( buttonsArea, text );
     createSpacer( buttonsArea );
     okButton = createButton( buttonsArea, SWT.getMessage( "SWT_OK" ) );
     parent.getShell().setDefaultButton( okButton );
     okButton.forceFocus();
     okButton.addListener( SWT.Selection, new Listener() {
       public void handleEvent( Event event ) {
         okPressed();
       }
     } );
     Button cancelButton = createButton( buttonsArea, SWT.getMessage( "SWT_Cancel" ) );
     cancelButton.addListener( SWT.Selection, new Listener() {
       public void handleEvent( Event event ) {
         cancelPressed();
       }
     } );
   }

   protected FileUpload createFileUpload( Composite parent, String text ) {
     FileUpload fileUpload = new FileUpload( parent, isMulti() ? SWT.MULTI : SWT.NONE );
     fileUpload.setText( text );
     fileUpload.setLayoutData( createButtonLayoutData( fileUpload ) );
     fileUpload.addListener( SWT.Selection, new Listener() {
       public void handleEvent( Event event ) {
         handleFileUploadSelection( ( FileUpload )event.widget );
       }
     } );
     fileUpload.moveAbove( null );
     return fileUpload;
   }

   private void createSpacer( Composite buttonArea ) {
     spacer = new Label( buttonArea, SWT.NONE );
     spacer.setLayoutData( createButtonLayoutData( spacer ) );
   }

   protected Button createButton( Composite parent, String text ) {
     Button button = new Button( parent, SWT.PUSH );
     button.setText( text );
     button.setLayoutData( createButtonLayoutData( button ) );
     return button;
   }

   private void handleFileUploadSelection( FileUpload fileUpload ) {
     placeHolder.dispose();
     UploadPanel uploadPanel = createUploadPanel( fileUpload.getFileNames() );
     updateScrolledComposite();
     updateButtonsArea( fileUpload );
     Uploader uploader = new UploaderWidget( fileUpload );
     FileUploadHandler handler = new FileUploadHandler( new DiskFileUploadReceiver() );
     FileUploadRunnable uploadRunnable = new FileUploadRunnable( uploadPanel,
                                                                 progressCollector,
                                                                 uploader,
                                                                 handler );
     singleThreadExecutor.execute( uploadRunnable );
   }

   private void updateScrolledComposite() {
     Composite content = ( Composite )uploadsScroller.getContent();
     for( int i = 0; i < 2; i++ ) { // workaround for bug 414868
       Rectangle clientArea = uploadsScroller.getClientArea();
       Point minSize = content.computeSize( clientArea.width, SWT.DEFAULT );
       uploadsScroller.setMinSize( minSize );
     }
     uploadsScroller.setOrigin( 0, 10000 );
     content.layout();
   }

   private void updateButtonsArea( FileUpload fileUpload ) {
     if( isMulti() ) {
       Composite buttonsArea = fileUpload.getParent();
       hideFileUpload( fileUpload );
       createFileUpload( buttonsArea, SWT.getMessage( "SWT_Add" ) );
       buttonsArea.layout();
     } else {
       fileUpload.setEnabled( false );
     }
   }

   private UploadPanel createUploadPanel( String[] fileNames ) {
     Composite parent = ( Composite )uploadsScroller.getContent();
     UploadPanel uploadPanel = new UploadPanel( parent, fileNames );
     uploadPanel.setLayoutData( createHorizontalFillData() );
     return uploadPanel;
   }

   private static void hideFileUpload( FileUpload fileUpload ) {
     GridData layoutData = createButtonLayoutData( fileUpload );
     layoutData.exclude = true;
     fileUpload.setLayoutData( layoutData );
     fileUpload.setVisible( false );
   }

   private void setButtonEnabled( final boolean enabled ) {
     if( !display.isDisposed() ) {
       display.asyncExec( new Runnable() {
         public void run() {
           if( !okButton.isDisposed() ) {
             okButton.setEnabled( enabled );
           }
         }
       } );
     }
   }

   private void okPressed() {
     setReturnCode( SWT.OK );
     close();
   }

   private void cancelPressed() {
     setReturnCode( SWT.CANCEL );
     close();
   }

   private void setReturnCode( int code ) {
     returnCode = code;
   }

   private boolean isMulti() {
     return ( getStyle() & SWT.MULTI ) != 0;
   }

   private void close() {
     shell.close();
   }

   private void cleanup() {
     pushSession.stop();
     singleThreadExecutor.shutdownNow();
     if( returnCode == SWT.CANCEL ) {
       deleteUploadedFiles( progressCollector.getCompletedFileNames() );
     }
   }

   void deleteUploadedFiles( String[] fileNames ) {
     for( String fileName : fileNames ) {
       File file = new File( fileName );
       if( file.exists() ) {
         file.delete();
       }
     }
   }

   static int checkStyle( Shell parent, int style ) {
     int result = style;
     int mask = SWT.PRIMARY_MODAL | SWT.APPLICATION_MODAL | SWT.SYSTEM_MODAL;
     if( ( result & SWT.SHEET ) != 0 ) {
       result &= ~SWT.SHEET;
       if( ( result & mask ) == 0 ) {
         result |= parent == null ? SWT.APPLICATION_MODAL : SWT.PRIMARY_MODAL;
       }
     }
     if( ( result & mask ) == 0 ) {
       result |= SWT.APPLICATION_MODAL;
     }
     if( ( result & ( SWT.LEFT_TO_RIGHT ) ) == 0 ) {
       if( parent != null ) {
         if( ( parent.getStyle() & SWT.LEFT_TO_RIGHT ) != 0 ) {
           result |= SWT.LEFT_TO_RIGHT;
         }
       }
     }
     result |= SWT.TITLE | SWT.BORDER;
     result &= ~SWT.MIN;
     return result;
   }

   ThreadPoolExecutor createSingleThreadExecutor() {
     return new SingleThreadExecutor();
   }

   private final class SingleThreadExecutor extends ThreadPoolExecutor {

     public SingleThreadExecutor() {
       super( 1, 1, 0L, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<Runnable>() );
     }

     @Override
     protected void beforeExecute( Thread thread, Runnable runnable ) {
       setButtonEnabled( false );
     }

     @Override
     protected void afterExecute( Runnable runnable, Throwable throwable ) {
       if( getQueue().size() == 0 ) {
         setButtonEnabled( true );
       }
     }

   }

 }
	/*******************************************************************************
	* Copyright (c) 2000, 2014 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	* Austin Riddle (Texas Center for Applied Technology) - RAP implementation
	* EclipseSource - ongoing development
	*******************************************************************************/
	package org.eclipse.swt.widgets;

	import static org.eclipse.swt.internal.widgets.LayoutUtil.createButtonLayoutData;
	import static org.eclipse.swt.internal.widgets.LayoutUtil.createFillData;
	import static org.eclipse.swt.internal.widgets.LayoutUtil.createGridLayout;
	import static org.eclipse.swt.internal.widgets.LayoutUtil.createHorizontalFillData;

	import java.io.File;
	import java.util.concurrent.LinkedBlockingQueue;
	import java.util.concurrent.ThreadPoolExecutor;
	import java.util.concurrent.TimeUnit;

	import org.eclipse.rap.addons.fileupload.DiskFileUploadReceiver;
	import org.eclipse.rap.addons.fileupload.FileUploadHandler;
	import org.eclipse.rap.rwt.client.ClientFile;
	import org.eclipse.rap.rwt.dnd.ClientFileTransfer;
	import org.eclipse.rap.rwt.service.ServerPushSession;
	import org.eclipse.rap.rwt.widgets.FileUpload;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.SWTException;
	import org.eclipse.swt.custom.ScrolledComposite;
	import org.eclipse.swt.dnd.DND;
	import org.eclipse.swt.dnd.DropTarget;
	import org.eclipse.swt.dnd.DropTargetAdapter;
	import org.eclipse.swt.dnd.DropTargetEvent;
	import org.eclipse.swt.dnd.Transfer;
	import org.eclipse.swt.events.ControlAdapter;
	import org.eclipse.swt.events.ControlEvent;
	import org.eclipse.swt.events.DisposeEvent;
	import org.eclipse.swt.events.DisposeListener;
	import org.eclipse.swt.graphics.Point;
	import org.eclipse.swt.graphics.Rectangle;
	import org.eclipse.swt.internal.widgets.FileUploadRunnable;
	import org.eclipse.swt.internal.widgets.ProgressCollector;
	import org.eclipse.swt.internal.widgets.UploadPanel;
	import org.eclipse.swt.internal.widgets.Uploader;
	import org.eclipse.swt.internal.widgets.UploaderService;
	import org.eclipse.swt.internal.widgets.UploaderWidget;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.layout.GridLayout;


	/**
	* Instances of this class allow the user to navigate the file system and select
	* a file name. The selected file will be uploaded to the server and the path
	* made available as the result of the dialog.
	* <dl>
	* <dt><b>Styles:</b></dt>
	* <dd><!--SAVE, OPEN,--> MULTI</dd>
	* <dt><b>Events:</b></dt>
	* <dd>(none)</dd>
	* </dl>
	* <p>
	* The OPEN style is applied by default and setting any other styles has no
	* effect. <!--Note: Only one of the styles SAVE and OPEN may be specified.-->
	* </p>
	* <p>
	* IMPORTANT: This class is intended to be subclassed <em>only</em> within the
	* SWT implementation.
	* </p>
	*
	* @see <a href="http://www.eclipse.org/swt/snippets/#filedialog">FileDialog
	* snippets</a>
	* @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example:
	* ControlExample, Dialog tab</a>
	* @see <a href="http://www.eclipse.org/swt/">Sample code and further
	* information</a>
	*/
	public class FileDialog extends Dialog {

	private final ServerPushSession pushSession;
	private final ThreadPoolExecutor singleThreadExecutor;
	private Display display;
	private ScrolledComposite uploadsScroller;
	private Button okButton;
	private Label spacer;
	private UploadPanel placeHolder;
	private ProgressCollector progressCollector;

	/**
	* Constructs a new instance of this class given only its parent.
	*
	* @param parent a shell which will be the parent of the new instance
	* @exception IllegalArgumentException <ul>
	* <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
	* </ul>
	* @exception SWTException <ul>
	* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the
	* thread that created the parent</li>
	* <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed
	* subclass</li>
	* </ul>
	*/
	public FileDialog( Shell parent ) {
	this( parent, SWT.TITLE \| SWT.BORDER \| SWT.APPLICATION_MODAL );
	}

	/**
	* Constructs a new instance of this class given its parent and a style value
	* describing its behavior and appearance.
	* <p>
	* The style value is either one of the style constants defined in class
	* <code>SWT</code> which is applicable to instances of this class, or must be
	* built by <em>bitwise OR</em>'ing together (that is, using the
	* <code>int</code> "\|" operator) two or more of those <code>SWT</code> style
	* constants. The class description lists the style constants that are
	* applicable to the class. Style bits are also inherited from superclasses.
	* </p>
	*
	* @param parent a shell which will be the parent of the new instance
	* @param style the style of dialog to construct
	* @exception IllegalArgumentException <ul>
	* <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
	* </ul>
	* @exception SWTException <ul>
	* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the
	* thread that created the parent</li>
	* <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed
	* subclass</li>
	* </ul>
	*/
	public FileDialog( Shell parent, int style ) {
	super( parent, checkStyle( parent, style ) );
	checkSubclass();
	pushSession = new ServerPushSession();
	singleThreadExecutor = createSingleThreadExecutor();
	}

	/**
	* Returns the path of the first file that was selected in the dialog relative
	* to the filter path, or an empty string if no such file has been selected.
	*
	* @return the relative path of the file
	*/
	public String getFileName() {
	String[] fileNames = getFileNames();
	return fileNames.length == 0 ? "" : fileNames[ 0 ];
	}

	/**
	* Returns a (possibly empty) array with the paths of all files that were
	* selected in the dialog relative to the filter path.
	*
	* @return the relative paths of the files
	*/
	public String[] getFileNames() {
	return returnCode == SWT.OK ? progressCollector.getCompletedFileNames() : new String[ 0 ];
	}

	/**
	* Makes the dialog visible and brings it to the front
	* of the display.
	*
	* @return a string describing the absolute path of the first selected file,
	* or null if the dialog was cancelled or an error occurred
	*
	* @exception SWTException <ul>
	* <li>ERROR_WIDGET_DISPOSED - if the dialog has been disposed</li>
	* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the dialog</li>
	* </ul>
	*/
	public String open() {
	prepareOpen();
	runEventLoop( shell );
	return returnCode == SWT.OK ? getFileName() : null;
	}

	@Override
	protected void prepareOpen() {
	createShell();
	createControls();
	initializeBounds();
	initializeDefaults();
	pushSession.start();
	}

	private void createShell() {
	shell = new Shell( getParent(), getStyle() );
	shell.setText( getText() );
	shell.addDisposeListener( new DisposeListener() {
	public void widgetDisposed( DisposeEvent event ) {
	cleanup();
	}
	} );
	display = shell.getDisplay();
	}

	private void initializeBounds() {
	Point prefSize = shell.computeSize( SWT.DEFAULT, SWT.DEFAULT );
	if( isMulti() ) {
	prefSize.y += 165; // ensure space for five files
	}
	shell.setMinimumSize( prefSize );
	Rectangle parentSize = getParent().getBounds();
	int locationX = ( parentSize.width - prefSize.x ) / 2 + parentSize.x;
	int locationY = ( parentSize.height - prefSize.y ) / 2 + parentSize.y;
	shell.setBounds( locationX, locationY, prefSize.x, prefSize.y );
	// set spacer real layout data after shell prefer size calculation
	spacer.setLayoutData( createHorizontalFillData() );
	}

	private void initializeDefaults() {
	setReturnCode( SWT.CANCEL );
	}

	private void createControls() {
	shell.setLayout( createGridLayout( 1, 10, 10 ) );
	createDialogArea( shell );
	createButtonsArea( shell );
	}

	private void createDialogArea( Composite parent ) {
	Composite dialogArea = new Composite( parent, SWT.NONE );
	dialogArea.setLayoutData( createFillData() );
	dialogArea.setLayout( createGridLayout( 1, 0, 5 ) );
	createUploadsArea( dialogArea );
	createProgressArea( dialogArea );
	createDropTarget( dialogArea );
	}

	private void createUploadsArea( Composite parent ) {
	uploadsScroller = new ScrolledComposite( parent, isMulti() ? SWT.V_SCROLL : SWT.NONE );
	uploadsScroller.setLayoutData( createFillData() );
	uploadsScroller.setExpandHorizontal( true );
	uploadsScroller.setExpandVertical( true );
	Composite scrolledContent = new Composite( uploadsScroller, SWT.NONE );
	scrolledContent.setLayout( new GridLayout( 1, false ) );
	uploadsScroller.setContent( scrolledContent );
	uploadsScroller.addControlListener( new ControlAdapter() {
	@Override
	public void controlResized( ControlEvent event ) {
	updateScrolledComposite();
	}
	} );
	placeHolder = new UploadPanel( scrolledContent, new String[] { "" } );
	placeHolder.setLayoutData( createHorizontalFillData() );
	}

	private void createProgressArea( Composite parent ) {
	progressCollector = new ProgressCollector( parent );
	progressCollector.setLayoutData( createHorizontalFillData() );
	}

	private void createDropTarget( Control control ) {
	DropTarget dropTarget = new DropTarget( control, DND.DROP_MOVE \| DND.DROP_COPY );
	dropTarget.setTransfer( new Transfer[] { ClientFileTransfer.getInstance() } );
	dropTarget.addDropListener( new DropTargetAdapter() {
	@Override
	public void dropAccept( DropTargetEvent event ) {
	if( !ClientFileTransfer.getInstance().isSupportedType( event.currentDataType ) ) {
	event.detail = DND.DROP_NONE;
	}
	}
	@Override
	public void drop( DropTargetEvent event ) {
	handleFileDrop( ( ClientFile[] )event.data );
	}
	} );
	}

	private void handleFileDrop( ClientFile[] clientFiles ) {
	placeHolder.dispose();
	ClientFile[] files = isMulti() ? clientFiles : new ClientFile[] { clientFiles[ 0 ] };
	UploadPanel uploadPanel = createUploadPanel( getFileNames( files ) );
	updateScrolledComposite();
	Uploader uploader = new UploaderService( files );
	FileUploadHandler handler = new FileUploadHandler( new DiskFileUploadReceiver() );
	FileUploadRunnable uploadRunnable = new FileUploadRunnable( uploadPanel,
	progressCollector,
	uploader,
	handler );
	singleThreadExecutor.execute( uploadRunnable );
	}

	private static String[] getFileNames( ClientFile[] clientFiles ) {
	String[] fileNames = new String[ clientFiles.length ];
	for( int i = 0; i < fileNames.length; i++ ) {
	fileNames[ i ] = clientFiles[ i ].getName();
	}
	return fileNames;
	}

	private void createButtonsArea( Composite parent ) {
	Composite buttonsArea = new Composite( parent, SWT.NONE );
	buttonsArea.setLayout( createGridLayout( 4, 0, 5 ) );
	buttonsArea.setLayoutData( createHorizontalFillData() );
	String text = isMulti() ? SWT.getMessage( "SWT_Add" ) : SWT.getMessage( "SWT_Browse" );
	createFileUpload( buttonsArea, text );
	createSpacer( buttonsArea );
	okButton = createButton( buttonsArea, SWT.getMessage( "SWT_OK" ) );
	parent.getShell().setDefaultButton( okButton );
	okButton.forceFocus();
	okButton.addListener( SWT.Selection, new Listener() {
	public void handleEvent( Event event ) {
	okPressed();
	}
	} );
	Button cancelButton = createButton( buttonsArea, SWT.getMessage( "SWT_Cancel" ) );
	cancelButton.addListener( SWT.Selection, new Listener() {
	public void handleEvent( Event event ) {
	cancelPressed();
	}
	} );
	}

	protected FileUpload createFileUpload( Composite parent, String text ) {
	FileUpload fileUpload = new FileUpload( parent, isMulti() ? SWT.MULTI : SWT.NONE );
	fileUpload.setText( text );
	fileUpload.setLayoutData( createButtonLayoutData( fileUpload ) );
	fileUpload.addListener( SWT.Selection, new Listener() {
	public void handleEvent( Event event ) {
	handleFileUploadSelection( ( FileUpload )event.widget );
	}
	} );
	fileUpload.moveAbove( null );
	return fileUpload;
	}

	private void createSpacer( Composite buttonArea ) {
	spacer = new Label( buttonArea, SWT.NONE );
	spacer.setLayoutData( createButtonLayoutData( spacer ) );
	}

	protected Button createButton( Composite parent, String text ) {
	Button button = new Button( parent, SWT.PUSH );
	button.setText( text );
	button.setLayoutData( createButtonLayoutData( button ) );
	return button;
	}

	private void handleFileUploadSelection( FileUpload fileUpload ) {
	placeHolder.dispose();
	UploadPanel uploadPanel = createUploadPanel( fileUpload.getFileNames() );
	updateScrolledComposite();
	updateButtonsArea( fileUpload );
	Uploader uploader = new UploaderWidget( fileUpload );
	FileUploadHandler handler = new FileUploadHandler( new DiskFileUploadReceiver() );
	FileUploadRunnable uploadRunnable = new FileUploadRunnable( uploadPanel,
	progressCollector,
	uploader,
	handler );
	singleThreadExecutor.execute( uploadRunnable );
	}

	private void updateScrolledComposite() {
	Composite content = ( Composite )uploadsScroller.getContent();
	for( int i = 0; i < 2; i++ ) { // workaround for bug 414868
	Rectangle clientArea = uploadsScroller.getClientArea();
	Point minSize = content.computeSize( clientArea.width, SWT.DEFAULT );
	uploadsScroller.setMinSize( minSize );
	}
	uploadsScroller.setOrigin( 0, 10000 );
	content.layout();
	}

	private void updateButtonsArea( FileUpload fileUpload ) {
	if( isMulti() ) {
	Composite buttonsArea = fileUpload.getParent();
	hideFileUpload( fileUpload );
	createFileUpload( buttonsArea, SWT.getMessage( "SWT_Add" ) );
	buttonsArea.layout();
	} else {
	fileUpload.setEnabled( false );
	}
	}

	private UploadPanel createUploadPanel( String[] fileNames ) {
	Composite parent = ( Composite )uploadsScroller.getContent();
	UploadPanel uploadPanel = new UploadPanel( parent, fileNames );
	uploadPanel.setLayoutData( createHorizontalFillData() );
	return uploadPanel;
	}

	private static void hideFileUpload( FileUpload fileUpload ) {
	GridData layoutData = createButtonLayoutData( fileUpload );
	layoutData.exclude = true;
	fileUpload.setLayoutData( layoutData );
	fileUpload.setVisible( false );
	}

	private void setButtonEnabled( final boolean enabled ) {
	if( !display.isDisposed() ) {
	display.asyncExec( new Runnable() {
	public void run() {
	if( !okButton.isDisposed() ) {
	okButton.setEnabled( enabled );
	}
	}
	} );
	}
	}

	private void okPressed() {
	setReturnCode( SWT.OK );
	close();
	}

	private void cancelPressed() {
	setReturnCode( SWT.CANCEL );
	close();
	}

	private void setReturnCode( int code ) {
	returnCode = code;
	}

	private boolean isMulti() {
	return ( getStyle() & SWT.MULTI ) != 0;
	}

	private void close() {
	shell.close();
	}

	private void cleanup() {
	pushSession.stop();
	singleThreadExecutor.shutdownNow();
	if( returnCode == SWT.CANCEL ) {
	deleteUploadedFiles( progressCollector.getCompletedFileNames() );
	}
	}

	void deleteUploadedFiles( String[] fileNames ) {
	for( String fileName : fileNames ) {
	File file = new File( fileName );
	if( file.exists() ) {
	file.delete();
	}
	}
	}

	static int checkStyle( Shell parent, int style ) {
	int result = style;
	int mask = SWT.PRIMARY_MODAL \| SWT.APPLICATION_MODAL \| SWT.SYSTEM_MODAL;
	if( ( result & SWT.SHEET ) != 0 ) {
	result &= ~SWT.SHEET;
	if( ( result & mask ) == 0 ) {
	result \|= parent == null ? SWT.APPLICATION_MODAL : SWT.PRIMARY_MODAL;
	}
	}
	if( ( result & mask ) == 0 ) {
	result \|= SWT.APPLICATION_MODAL;
	}
	if( ( result & ( SWT.LEFT_TO_RIGHT ) ) == 0 ) {
	if( parent != null ) {
	if( ( parent.getStyle() & SWT.LEFT_TO_RIGHT ) != 0 ) {
	result \|= SWT.LEFT_TO_RIGHT;
	}
	}
	}
	result \|= SWT.TITLE \| SWT.BORDER;
	result &= ~SWT.MIN;
	return result;
	}

	ThreadPoolExecutor createSingleThreadExecutor() {
	return new SingleThreadExecutor();
	}

	private final class SingleThreadExecutor extends ThreadPoolExecutor {

	public SingleThreadExecutor() {
	super( 1, 1, 0L, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<Runnable>() );
	}

	@Override
	protected void beforeExecute( Thread thread, Runnable runnable ) {
	setButtonEnabled( false );
	}

	@Override
	protected void afterExecute( Runnable runnable, Throwable throwable ) {
	if( getQueue().size() == 0 ) {
	setButtonEnabled( true );
	}
	}

	}

	}