Program: 78893
Project: 78893
Buggy source:
public void modify(Object element,String property,Object value){
  if (element instanceof Item) {
    element=((Item)element).getData();
  }
  SelectionChoice choice=((SelectionChoice)element);
{
    String newValue=UIUtil.convertToModelString((String)value,false);
    if (COLUMN_VALUE.equals(property)) {
      String errorMessage=isValidValue(newValue);
      if (errorMessage != null) {
        ExceptionHandler.openMessageBox(ERROR_TITLE_INVALID_INPUT,errorMessage,SWT.ICON_INFORMATION);
        return;
      }
      if (choice.getLabel() == null && containValue(choice,newValue,COLUMN_DISPLAY_TEXT)) {
        ExceptionHandler.openMessageBox(ERROR_TITLE_INVALID_INPUT,ERROR_MSG_DUPLICATED_LABEL,SWT.ICON_INFORMATION);
        return;
      }
    }
    newValue=convertToStandardFormat(newValue);
    if (containValue(choice,newValue,property)) {
      if (COLUMN_DISPLAY_TEXT.equals(property)) {
        ExceptionHandler.openMessageBox(ERROR_TITLE_INVALID_INPUT,ERROR_MSG_DUPLICATED_LABEL,SWT.ICON_INFORMATION);
      }
 else {
        ExceptionHandler.openMessageBox(ERROR_TITLE_INVALID_INPUT,ERROR_MSG_DUPLICATED_VALUE,SWT.ICON_INFORMATION);
      }
      return;
    }
    if (choice == dummyChoice) {
      choice=StructureFactory.createSelectionChoice();
      choiceList.add(choice);
    }
    if (COLUMN_VALUE.equals(property)) {
      if (isDefaultChoice(choice) && !PARAM_CONTROL_LIST.equals(getSelectedControlType())) {
        defaultValue=newValue;
      }
      choice.setValue(newValue);
    }
 else     if (COLUMN_DISPLAY_TEXT.equals(property)) {
      choice.setLabel(newValue);
    }
  }
  refreshValueTable();
}

Fixed version (ground truth):
public void modify(Object element,String property,Object value){
  if (element instanceof Item) {
    element=((Item)element).getData();
  }
  SelectionChoice choice=((SelectionChoice)element);
{
    String newValue=UIUtil.convertToModelString((String)value,false);
    if (COLUMN_VALUE.equals(property)) {
      String errorMessage=isValidValue(newValue);
      if (errorMessage != null) {
        ExceptionHandler.openMessageBox(ERROR_TITLE_INVALID_INPUT,errorMessage,SWT.ICON_INFORMATION);
        return;
      }
      if (choice.getLabel() == null && containValue(choice,newValue,COLUMN_DISPLAY_TEXT)) {
        ExceptionHandler.openMessageBox(ERROR_TITLE_INVALID_INPUT,ERROR_MSG_DUPLICATED_LABEL,SWT.ICON_INFORMATION);
        return;
      }
    }
    newValue=convertToStandardFormat(newValue);
    if (containValue(choice,newValue,property)) {
      if (COLUMN_DISPLAY_TEXT.equals(property)) {
        ExceptionHandler.openMessageBox(ERROR_TITLE_INVALID_INPUT,ERROR_MSG_DUPLICATED_LABEL,SWT.ICON_INFORMATION);
      }
 else {
        ExceptionHandler.openMessageBox(ERROR_TITLE_INVALID_INPUT,ERROR_MSG_DUPLICATED_VALUE,SWT.ICON_INFORMATION);
      }
      return;
    }
    if (choice == dummyChoice) {
      choice=StructureFactory.createSelectionChoice();
      choiceList.add(choice);
    }
    if (COLUMN_VALUE.equals(property)) {
      if (isDefaultChoice(choice)) {
        defaultValue=newValue;
      }
      choice.setValue(newValue);
    }
 else     if (COLUMN_DISPLAY_TEXT.equals(property)) {
      choice.setLabel(newValue);
    }
  }
  refreshValueTable();
}