/**
  * Returns the error message count.
  *
  * @param correlationId correlation Id.
  * @return the error message count.
  */
 @ManagedOperation
 @ManagedOperationParameters({
   @ManagedOperationParameter(name = "correlationId", description = "Correlation ID")
 })
 public int getTaskErrorMessageCount(String correlationId) {
   return taskExecutor.getTaskResult(correlationId).getErrorMessageCount();
 }
 /**
  * Returns task error messages.
  *
  * @param correlationId correlation Id.
  * @return task error messages.
  */
 @ManagedOperation
 @ManagedOperationParameters({
   @ManagedOperationParameter(name = "correlationId", description = "Correlation ID")
 })
 public String getTaskErrorMessages(String correlationId) {
   Map<String, TaskItemResult> taskItems =
       taskExecutor.getTaskResult(correlationId).getTaskItems();
   if (!taskItems.isEmpty()) {
     StringBuilder errors = new StringBuilder();
     for (TaskItemResult taskItemResult : taskItems.values()) {
       errors.append("[").append(taskItemResult).append("]");
     }
     return errors.toString();
   }
   return "";
 }