Package org.apache.lucene.codecs.uniformsplit.sharedterms

Class STMergingTermsEnum

  • All Implemented Interfaces:
    BytesRefIterator
    public class STMergingTermsEnum
extends TermsEnum
    Combines PostingsEnum for the same term for a given field from multiple segments. It is used during segment merging.

    • Constructor Detail

      • STMergingTermsEnum

        protected STMergingTermsEnum​(java.lang.String fieldName,
                             int numSegments)
        Constructs a STMergingTermsEnum for a given field.

    • Method Detail

      • seekExact

        public boolean seekExact​(BytesRef text)
                  throws java.io.IOException
        Description copied from class: TermsEnum
        Attempts to seek to the exact term, returning true if the term is found. If this returns false, the enum is unpositioned. For some codecs, seekExact may be substantially faster than TermsEnum.seekCeil(org.apache.lucene.util.BytesRef).

        Specified by:
        seekExact in class TermsEnum
        Returns:
        true if the term is found; return false if the enum is unpositioned.
        Throws:
        java.io.IOException

      • seekCeil

        public TermsEnum.SeekStatus seekCeil​(BytesRef text)
        Description copied from class: TermsEnum
        Seeks to the specified term, if it exists, or to the next (ceiling) term. Returns SeekStatus to indicate whether exact term was found, a different term was found, or EOF was hit. The target term may be before or after the current term. If this returns SeekStatus.END, the enum is unpositioned.
        Specified by:
        seekCeil in class TermsEnum

      • seekExact

        public void seekExact​(long ord)
        Description copied from class: TermsEnum
        Seeks to the specified term by ordinal (position) as previously returned by TermsEnum.ord(). The target ord may be before or after the current ord, and must be within bounds.
        Specified by:
        seekExact in class TermsEnum

      • seekExact

        public void seekExact​(BytesRef term,
                      TermState state)
               throws java.io.IOException
        Description copied from class: TermsEnum
        Expert: Seeks a specific position by TermState previously obtained from TermsEnum.termState(). Callers should maintain the TermState to use this method. Low-level implementations may position the TermsEnum without re-seeking the term dictionary.

        Seeking by TermState should only be used iff the state was obtained from the same TermsEnum instance.

        NOTE: Using this method with an incompatible TermState might leave this TermsEnum in undefined state. On a segment level TermState instances are compatible only iff the source and the target TermsEnum operate on the same field. If operating on segment level, TermState instances must not be used across segments.

        NOTE: A seek by TermState might not restore the AttributeSource's state. AttributeSource states must be maintained separately if this method is used.

        Specified by:
        seekExact in class TermsEnum
        Parameters:
        term - the term the TermState corresponds to
        state - the TermState
        Throws:
        java.io.IOException

      • term

        public BytesRef term()
        Description copied from class: TermsEnum
        Returns current term. Do not call this when the enum is unpositioned.
        Specified by:
        term in class TermsEnum

      • ord

        public long ord()
        Description copied from class: TermsEnum
        Returns ordinal position for current term. This is an optional method (the codec may throw UnsupportedOperationException). Do not call this when the enum is unpositioned.
        Specified by:
        ord in class TermsEnum

      • docFreq

        public int docFreq()
        Description copied from class: TermsEnum
        Returns the number of documents containing the current term. Do not call this when the enum is unpositioned. TermsEnum.SeekStatus.END.
        Specified by:
        docFreq in class TermsEnum

      • totalTermFreq

        public long totalTermFreq()
        Description copied from class: TermsEnum
        Returns the total number of occurrences of this term across all documents (the sum of the freq() for each doc that has this term). Note that, like other term measures, this measure does not take deleted documents into account.
        Specified by:
        totalTermFreq in class TermsEnum

      • postings

        public PostingsEnum postings​(PostingsEnum reuse,
                             int flags)
        Description copied from class: TermsEnum
        Get PostingsEnum for the current term, with control over whether freqs, positions, offsets or payloads are required. Do not call this when the enum is unpositioned. This method will not return null.

        NOTE: the returned iterator may return deleted documents, so deleted documents have to be checked on top of the PostingsEnum.

        Specified by:
        postings in class TermsEnum
        Parameters:
        reuse - pass a prior PostingsEnum for possible reuse
        flags - specifies which optional per-document values you require; see PostingsEnum.FREQS

      • next

        public BytesRef next()
        Description copied from interface: BytesRefIterator
        Increments the iteration to the next BytesRef in the iterator. Returns the resulting BytesRef or null if the end of the iterator is reached. The returned BytesRef may be re-used across calls to next. After this method returns null, do not call it again: the results are undefined.
        Returns:
        the next BytesRef in the iterator or null if the end of the iterator is reached.