Program: 147517
Project: 147517
Buggy source:
/** 
 * This method add the current user to the followers list of a given requirement
 * @param projectId     the ID of the project of the requirement.
 * @param componentId   the id of the component under a given project
 * @param requirementId the ID of the requirement.
 * @return
 */
@POST @Path("String_Node_Str") @Consumes(MediaType.APPLICATION_JSON) @Produces(MediaType.APPLICATION_JSON) @Summary("String_Node_Str") @ApiResponses(value={@ApiResponse(code=200,message="String_Node_Str")}) public String addUserToFollowers(@PathParam("String_Node_Str") int projectId,@PathParam("String_Node_Str") int componentId,@PathParam("String_Node_Str") int requirementId){
  long userId=((UserAgent)getActiveAgent()).getId();
  String registratorErrors=notifyRegistrators(EnumSet.of(BazaarFunction.VALIDATION,BazaarFunction.USER_FIRST_LOGIN_HANDLING));
  if (registratorErrors != null)   return registratorErrors;
  String resultJSON="String_Node_Str";
  DALFacade dalFacade=null;
  try {
    dalFacade=createConnection();
    Integer internalUserId=dalFacade.getUserIdByLAS2PeerId((int)userId);
    if (internalUserId == null) {
      resultJSON="String_Node_Str";
    }
 else {
      dalFacade.follow(internalUserId,requirementId);
    }
  }
 catch (  BazaarException bex) {
    resultJSON=ExceptionHandler.getInstance().toJSON(bex);
  }
catch (  Exception ex) {
    BazaarException bazaarException=ExceptionHandler.getInstance().convert(ex,ExceptionLocation.BAZAARSERVICE,ErrorCode.UNKNOWN,"String_Node_Str");
    resultJSON=ExceptionHandler.getInstance().toJSON(bazaarException);
  }
 finally {
    closeConnection(dalFacade);
  }
  return resultJSON;
}

Fixed version (ground truth):
/** 
 * This method add the current user to the followers list of a given requirement
 * @param projectId     the ID of the project of the requirement.
 * @param componentId   the id of the component under a given project
 * @param requirementId the ID of the requirement.
 * @return
 */
@POST @Path("String_Node_Str") @Produces(MediaType.APPLICATION_JSON) @Summary("String_Node_Str") @ApiResponses(value={@ApiResponse(code=200,message="String_Node_Str")}) public String addUserToFollowers(@PathParam("String_Node_Str") int projectId,@PathParam("String_Node_Str") int componentId,@PathParam("String_Node_Str") int requirementId){
  long userId=((UserAgent)getActiveAgent()).getId();
  String registratorErrors=notifyRegistrators(EnumSet.of(BazaarFunction.VALIDATION,BazaarFunction.USER_FIRST_LOGIN_HANDLING));
  if (registratorErrors != null)   return registratorErrors;
  String resultJSON="String_Node_Str";
  DALFacade dalFacade=null;
  try {
    dalFacade=createConnection();
    Integer internalUserId=dalFacade.getUserIdByLAS2PeerId((int)userId);
    if (internalUserId == null) {
      resultJSON="String_Node_Str";
    }
 else {
      dalFacade.follow(internalUserId,requirementId);
    }
  }
 catch (  BazaarException bex) {
    resultJSON=ExceptionHandler.getInstance().toJSON(bex);
  }
catch (  Exception ex) {
    BazaarException bazaarException=ExceptionHandler.getInstance().convert(ex,ExceptionLocation.BAZAARSERVICE,ErrorCode.UNKNOWN,"String_Node_Str");
    resultJSON=ExceptionHandler.getInstance().toJSON(bazaarException);
  }
 finally {
    closeConnection(dalFacade);
  }
  return resultJSON;
}