in flink-connector-cassandra/src/main/java/org/apache/flink/streaming/connectors/cassandra/CassandraSink.java [100:107]
public CassandraSink<IN> uid(String uid) {
if (useDataStreamSink) {
getSinkTransformation().setUid(uid);
} else {
getTransformation().setUid(uid);
}
return this;
}