Package org.apache.lucene.search.grouping

Class AllGroupHeadsCollector.GroupHead<T>

java.lang.Object
org.apache.lucene.search.grouping.AllGroupHeadsCollector.GroupHead<T>
Enclosing class:
AllGroupHeadsCollector<T>
public abstract static class AllGroupHeadsCollector.GroupHead<T> extends Object
Represents a group head. A group head is the most relevant document for a particular group. The relevancy is based is usually based on the sort.

The group head contains a group value with its associated most relevant document id.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    int
    doc
     
    protected int
    docBase
     
    final T
    groupValue
     

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    GroupHead(T groupValue, int doc, int docBase)
    Create a new GroupHead for the given value

  • Method Summary

    Modifier and Type
    Method
    Description
    protected abstract int
    compare(int compIDX, int doc)
    Compares the specified document for a specified comparator against the current most relevant document.
    protected void
    setNextReader(LeafReaderContext ctx)
    Called for each segment
    protected abstract void
    setScorer(Scorable scorer)
    Called for each segment
    protected abstract void
    updateDocHead(int doc)
    Updates the current most relevant document with the specified document.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • groupValue

      public final T groupValue

    • doc

      public int doc

    • docBase

      protected int docBase

  • Constructor Details

    • GroupHead

      protected GroupHead(T groupValue, int doc, int docBase)
      Create a new GroupHead for the given value

  • Method Details

    • setNextReader

      protected void setNextReader(LeafReaderContext ctx) throws IOException
      Called for each segment
      Throws:
      IOException

    • setScorer

      protected abstract void setScorer(Scorable scorer) throws IOException
      Called for each segment
      Throws:
      IOException

    • compare

      protected abstract int compare(int compIDX, int doc) throws IOException
      Compares the specified document for a specified comparator against the current most relevant document.
      Parameters:
      compIDX - The comparator index of the specified comparator.
      doc - The specified document.
      Returns:
      -1 if the specified document wasn't competitive against the current most relevant document, 1 if the specified document was competitive against the current most relevant document. Otherwise 0.
      Throws:
      IOException - If I/O related errors occur

    • updateDocHead

      protected abstract void updateDocHead(int doc) throws IOException
      Updates the current most relevant document with the specified document.
      Parameters:
      doc - The specified document
      Throws:
      IOException - If I/O related errors occur