Class FileUpload

All Implemented Interfaces:
Adaptable, Drawable

public class FileUpload extends Canvas
A button-like widget allowing to select a file from the client's file system and to upload this file to a given URL using HTTP POST. Multiple files may be selected if MULTI style is given, but not all clients may support it.

Note that although this class is a subclass of Composite, it does not make sense to set a layout on it.

Styles:
MULTI

Since:
2.0
  • Constructor Details

    • FileUpload

      public FileUpload(Composite parent, int style)
      Constructs a new instance of this class given its parent and a style value describing its behavior and appearance.

      The style value is either one of the style constants defined in class SWT which is applicable to instances of this class, or must be built by bitwise OR'ing together (that is, using the int "|" operator) two or more of those SWT style constants. The class description lists the style constants that are applicable to the class. Style bits are also inherited from superclasses.

      Parameters:
      parent - a composite control which will be the parent of the new instance (cannot be null)
      style - the style of control to construct
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the parent is null
      SWTException -
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent
      • ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass
  • Method Details

    • setText

      public void setText(String text)
      Sets the receiver's text.
      Parameters:
      text - the new text
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the text is null
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • getText

      public String getText()
      Returns the receiver's text, which will be an empty string if it has never been set.
      Returns:
      the receiver's text
      Throws:
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • setImage

      public void setImage(Image image)
      Sets the receiver's image to the argument, which may be null indicating that no image should be displayed.
      Parameters:
      image - the image to display on the receiver (may be null)
      Throws:
      IllegalArgumentException -
      • ERROR_INVALID_ARGUMENT - if the image has been disposed
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • getImage

      public Image getImage()
      Returns the receiver's image if it has one, or null if it does not.
      Returns:
      the receiver's image
      Throws:
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • getFileName

      public String getFileName()
      Returns the selected file name, without the path. If no file name has been selected, null is returned. If multiple files have been selected, the first is returned.
      Returns:
      the selected file name
      Throws:
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • getFileNames

      public String[] getFileNames()
      Returns a (possibly empty) array with the names of all files that were selected.
      Returns:
      the names of the selected files
      Throws:
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      Since:
      2.2
    • setFilterExtensions

      public void setFilterExtensions(String[] extensions)
      Set the file extensions which the widget will use to filter the files it shows to the argument, which may not be null.

      An extension filter string must be of the form ".extension".

      Parameters:
      extensions - the file extension filter
      Throws:
      IllegalArgumentException -
      • ERROR_INVALID_ARGUMENT - if the extensions is null
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      Since:
      3.2
    • getFilterExtensions

      public String[] getFilterExtensions()
      Returns the file extensions which the widget will use to filter the files it shows.
      Returns:
      the file extensions filter
      Since:
      3.2
    • submit

      public void submit(String url)
      Starts to upload the selected file to the given URL using HTTP POST. If no file has been selected, nothing happens.

      Note: Calling this method while a file is still uploading might interrupt the ongoing upload. Due to restrictions of the client, there is no feedback for success or failure of the upload. This information can only be obtained from the server that accepts the upload.

      Parameters:
      url - the URL to upload to, must not be null
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the url is null
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
    • addSelectionListener

      public void addSelectionListener(SelectionListener listener)
      Adds the listener to the collection of listeners who will be notified when the user changes the receiver's selection, by sending it one of the messages defined in the SelectionListener interface.

      widgetSelected is called when the selected file changes. widgetDefaultSelected is not called.

      Parameters:
      listener - the listener which should be notified when the user changes the receiver's selection
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the listener is null
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      See Also:
    • removeSelectionListener

      public void removeSelectionListener(SelectionListener listener)
      Removes the listener from the collection of listeners who will be notified when the user changes the receiver's selection.
      Parameters:
      listener - the listener which should no longer be notified
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the listener is null
      SWTException -
      • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
      • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
      See Also:
    • computeSize

      public Point computeSize(int wHint, int hHint, boolean changed)
      Description copied from class: Control
      Returns the preferred size of the receiver.

      The preferred size of a control is the size that it would best be displayed at. The width hint and height hint arguments allow the caller to ask a control questions such as "Given a particular width, how high does the control need to be to show all of the contents?" To indicate that the caller does not wish to constrain a particular dimension, the constant SWT.DEFAULT is passed for the hint.

      If the changed flag is true, it indicates that the receiver's contents have changed, therefore any caches that a layout manager containing the control may have been keeping need to be flushed. When the control is resized, the changed flag will be false, so layout manager caches can be retained.

      Overrides:
      computeSize in class Composite
      Parameters:
      wHint - the width hint (can be SWT.DEFAULT)
      hHint - the height hint (can be SWT.DEFAULT)
      changed - true if the control's contents have changed, and false otherwise
      Returns:
      the preferred size of the control.
      See Also:
    • setLayout

      public void setLayout(Layout layout)
      Description copied from class: Composite
      Sets the layout which is associated with the receiver to be the argument which may be null.
      Overrides:
      setLayout in class Composite
      Parameters:
      layout - the receiver's new layout or null
    • getChildren

      public Control[] getChildren()
      Description copied from class: Composite
      Returns a (possibly empty) array containing the receiver's children. Children are returned in the order that they are drawn. The topmost control appears at the beginning of the array. Subsequent controls draw beneath this control and appear later in the array.

      Note: This is not the actual structure used by the receiver to maintain its list of children, so modifying the array will not affect the receiver.

      Overrides:
      getChildren in class Composite
      Returns:
      an array of children
      See Also:
    • getAdapter

      public <T> T getAdapter(Class<T> adapter)
      Description copied from class: Widget
      Implementation of the Adaptable interface.

      IMPORTANT: This method is not part of the RWT public API. It is marked public only so that it can be shared within the packages provided by RWT. It should never be accessed from application code.

      Specified by:
      getAdapter in interface Adaptable
      Overrides:
      getAdapter in class Canvas
      Parameters:
      adapter - the lookup class
      Returns:
      an object that can be cast to the given class or null if there is no adapter associated with the given class.