Package org.apache.lucene.queries.function

Class ValueSource

java.lang.Object
org.apache.lucene.queries.function.ValueSource
Direct Known Subclasses:
BoolFunction, ConstNumberSource, DocFreqValueSource, DualFloatFunction, FieldCacheSource, LinearFloatFunction, LiteralValueSource, MaxDocValueSource, MultiFloatFunction, MultiFunction, MultiValueSource, NormValueSource, NumDocsValueSource, OrdFieldSource, QueryValueSource, RangeMapFloatFunction, ReciprocalFloatFunction, ReverseOrdFieldSource, ScaleFloatFunction, SingleFunction, SumTotalTermFreqValueSource, TaxonomyFacetSumValueSource.ScoreValueSource, TotalTermFreqValueSource
public abstract class ValueSource extends Object
Instantiates FunctionValues for a particular reader.
Often used when creating a FunctionQuery.

  • Constructor Details

    • ValueSource

      public ValueSource()

  • Method Details

    • getValues

      public abstract FunctionValues getValues(Map context, AtomicReaderContext readerContext) throws IOException
      Gets the values for this reader and the context that was previously passed to createWeight()
      Throws:
      IOException

    • equals

      public abstract boolean equals(Object o)
      Overrides:
      equals in class Object

    • hashCode

      public abstract int hashCode()
      Overrides:
      hashCode in class Object

    • description

      public abstract String description()
      description of field, used in explain()

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • createWeight

      public void createWeight(Map context, IndexSearcher searcher) throws IOException
      Implementations should propagate createWeight to sub-ValueSources which can optionally store weight info in the context. The context object will be passed to getValues() where this info can be retrieved.
      Throws:
      IOException

    • newContext

      public static Map newContext(IndexSearcher searcher)
      Returns a new non-threadsafe context map.

    • getSortField

      public SortField getSortField(boolean reverse)
      EXPERIMENTAL: This method is subject to change.

      Get the SortField for this ValueSource. Uses the getValues(java.util.Map, AtomicReaderContext) to populate the SortField.

      Parameters:
      reverse - true if this is a reverse sort.
      Returns:
      The SortField for the ValueSource