org.apache.solr.client.solrj.io.stream

Class OuterHashJoinStream

  • All Implemented Interfaces:
    Closeable, Serializable, AutoCloseable, Expressible, MapSerializable, MapWriter


    public class OuterHashJoinStream
    extends HashJoinStream
    implements Expressible
    Takes two streams (fullStream and hashStream) and joins them similar to an LeftOuterJoinStream. The difference in a OuterHashJoinStream is that the tuples in the hashStream will all be read and hashed when this stream is opened. This provides a few optimizations iff the hashStream has a relatively small number of documents. The difference between this and a HashJoinStream is that a tuple in the fullStream will be returned even if it doesn't have any matching tuples in the hashStream. You are expected to provide a set of fields for which the hash will be calculated from. If a tuple from the hashStream does not contain a value (ie, null) for one of the fields the hash is being computed on then that tuple will not be considered a match to anything. If a tuple from the fullStream does not contain a value (ie, null) for one of the fields the hash is being computed on then that tuple will be returned without any joined tuples from the hashStream
    See Also:
    Serialized Form