@Override
    public boolean equals(final Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        final RefDataProcessingInfo that = (RefDataProcessingInfo) o;
        return createTimeEpochMs == that.createTimeEpochMs &&
                effectiveTimeEpochMs == that.effectiveTimeEpochMs &&
                processingState == that.processingState;
    }
@return The time an entry for the associated ref stream definition was accessed,
truncated to the nearest PROCESSING_INFO_TRUNCATION_UNIT.
stroom-pipeline/src/main/java/stroom/pipeline/refdata/store/RefDataProcessingInfo.java