String delimiter = "";
for (T item : list) {
result.append(delimiter);
if( item instanceof ModelUser ){
ModelUser modelTmp = (ModelUser)item;
result.append(modelTmp.getUsername().toString().trim());
}else if( item instanceof ModelRepository ){
ModelRepository modelTmp = (ModelRepository)item;
result.append(modelTmp.getName().toString().trim());
}else if( item instanceof ModelReviewGroup ){
ModelReviewGroup modelTmp = (ModelReviewGroup)item;
result.append(modelTmp.getName().toString().trim());
}else{
result.append(item.toString().trim());
}
delimiter = ",";
}