@Override
protected List<DataSourceField> addDataSourceFields() {
List<DataSourceField> fields = super.addDataSourceFields();
DataSourceField idDataField = new DataSourceIntegerField(Field.ID, "ID");
idDataField.setPrimaryKey(true);
idDataField.setCanEdit(false);
fields.add(idDataField);
DataSourceTextField usernameField = createTextField(Field.NAME, MSG.common_title_username(), 3, 100, true);
// Don't allow characters that could be used in HTML intended for an XSS attack.
RegExpValidator regExpValidator = new RegExpValidator("[^&<]*");