private void createButtonPanel(Composite pageContent) {
    Composite buttonPanel = new Composite(pageContent, SWT.NONE);
    GridLayout layout = new GridLayout();
    layout.numColumns = 1;
    buttonPanel.setLayout(layout);

    GridData gridData = new GridData();
    gridData.grabExcessHorizontalSpace = false;
    gridData.grabExcessVerticalSpace = true;
    gridData.verticalAlignment = GridData.CENTER;
    gridData.horizontalAlignment = GridData.CENTER;
    buttonPanel.setLayoutData(gridData);

    addButton = new Button(buttonPanel, SWT.PUSH);
    addButton.setText(Messages._UI_ADD_BUTTON);
    gridData = new GridData();
    gridData.horizontalAlignment = GridData.FILL;
    gridData.verticalAlignment = GridData.CENTER;
    addButton.setLayoutData(gridData);
    addButton.addSelectionListener(new ButtonSelectListener());
    addButton.setToolTipText(Messages._UI_ADD_BUTTON_TOOL_TIP);
    addButton.setEnabled(false);

    removeButton = new Button(buttonPanel, SWT.PUSH);
    removeButton.setText(Messages._UI_REMOVE_BUTTON);
    gridData = new GridData();
    gridData.horizontalAlignment = GridData.FILL;
    gridData.verticalAlignment = GridData.CENTER;
    removeButton.setLayoutData(gridData);
    removeButton.addSelectionListener(new ButtonSelectListener());
    removeButton.setToolTipText(Messages._UI_REMOVE_BUTTON_TOOL_TIP);
    removeButton.setEnabled(false);

    removeAllButton = new Button(buttonPanel, SWT.PUSH);
    removeAllButton.setText(Messages._UI_REMOVE_ALL_BUTTON);
    gridData = new GridData();
    gridData.horizontalAlignment = GridData.FILL;
    gridData.verticalAlignment = GridData.CENTER;
    removeAllButton.setLayoutData(gridData);
    removeAllButton.addSelectionListener(new ButtonSelectListener());
    removeAllButton.setToolTipText(Messages._UI_REMOVE_ALL_BUTTON_TOOL_TIP);
    removeAllButton.setEnabled(false);
  }
  void createImportButton(Composite parent) {
    importButton = new Button(parent, SWT.PUSH);
    importButton.setText(Messages._UI_IMPORT_BUTTON);

    GridData gridData = new GridData();
    gridData.horizontalAlignment = GridData.CENTER;
    importButton.setLayoutData(gridData);
    importButton.addSelectionListener(
        new SelectionListener() {
          public void widgetDefaultSelected(SelectionEvent e) {}

          public void widgetSelected(SelectionEvent e) {
            FileSystemImportWizard importWizard = new FileSystemImportWizard();
            importWizard.init(workbench, selection);
            Shell shell = Display.getCurrent().getActiveShell();
            WizardDialog wizardDialog = new WizardDialog(shell, importWizard);
            wizardDialog.create();
            wizardDialog.open();
            sourceFileViewer.refresh();
          }
        });
    importButton.setToolTipText(Messages._UI_IMPORT_BUTTON_TOOL_TIP);
  }