/**
   * Create the file system selection area.
   *
   * @param composite
   * @param enabled the initial enablement state.
   */
  private void createFileSystemSelection(Composite composite, boolean enabled) {

    // Always use the default if that is all there is.
    if (FileSystemSupportRegistry.getInstance().hasOneFileSystem()) {
      return;
    }

    fileSystemSelectionArea = new FileSystemSelectionArea();
    fileSystemSelectionArea.createContents(composite);
    fileSystemSelectionArea.setEnabled(enabled);
  }
 public void setEnabled(boolean enabled) {
   if (mainComp != null) {
     mainComp.setEnabled(enabled);
   }
   if (uriLabel != null) {
     uriLabel.setEnabled(enabled);
   }
   if (browseButton != null) {
     browseButton.setEnabled(enabled);
   }
   if (uriField != null) {
     uriField.setEnabled(enabled);
   }
   if (fileSystemSelectionArea != null) {
     fileSystemSelectionArea.setEnabled(enabled);
   }
 }