@Override
    public StringBuilder getStringBuilder() {
      StringBuilder sb = super.getStringBuilder();
      if (getException() == null) {
        sb.append(" returning value=").append(value);
      }
      return sb;
    }
Processes this message. This method is invoked by the receiver of the message.

@param dm the distribution manager that is processing the message.
geode-core/src/main/java/org/apache/geode/internal/cache/partitioned/FetchEntryMessage.java