Class PostingsWriterBase

  • All Implemented Interfaces:, java.lang.AutoCloseable
    Direct Known Subclasses:

    public abstract class PostingsWriterBase
    extends PostingsConsumer
    Extension of PostingsConsumer to support pluggable term dictionaries.

    This class contains additional hooks to interact with the provided term dictionaries such as BlockTreeTermsWriter. If you want to re-use an existing implementation and are only interested in customizing the format of the postings list, extend this class instead.

    See Also:
    • Method Detail

      • init

        public abstract void init​(IndexOutput termsOut)
        Called once after startup, before any terms have been added. Implementations typically write a header to the provided termsOut.
      • newTermState

        public abstract BlockTermState newTermState()
        Return a newly created empty TermState
      • startTerm

        public abstract void startTerm()
        Start a new term. Note that a matching call to finishTerm(BlockTermState) is done, only if the term has at least one document.
      • finishTerm

        public abstract void finishTerm​(BlockTermState state)
        Finishes the current term. The provided BlockTermState contains the term's summary statistics, and will holds metadata from PBF when returned
      • encodeTerm

        public abstract void encodeTerm​(long[] longs,
                                        DataOutput out,
                                        FieldInfo fieldInfo,
                                        BlockTermState state,
                                        boolean absolute)
        Encode metadata as long[] and byte[]. absolute controls whether current term is delta encoded according to latest term. Usually elements in longs are file pointers, so each one always increases when a new term is consumed. out is used to write generic bytes, which are not monotonic. NOTE: sometimes long[] might contain "don't care" values that are unused, e.g. the pointer to postings list may not be defined for some terms but is defined for others, if it is designed to inline some postings data in term dictionary. In this case, the postings writer should always use the last value, so that each element in metadata long[] remains monotonic.
      • setField

        public abstract int setField​(FieldInfo fieldInfo)
        Sets the current field for writing, and returns the fixed length of long[] metadata (which is fixed per field), called when the writing switches to another field.
      • close

        public abstract void close()
        Specified by:
        close in interface java.lang.AutoCloseable
        Specified by:
        close in interface