cluster-common/src/main/java/com/streamsets/pipeline/cluster/Consumer.java
public void error(Throwable throwable) {
    if (consumerError == null) {
      consumerError = throwable;
      controlChannel.consumerError(throwable);
    }
  }
public void error(Throwable throwable) {
    if (consumerError == null) {
      consumerError = throwable;
      controlChannel.consumerError(throwable);
    }
  }
Send a control message indicating the consumer has encountered an error.