org.apache.lucene.search.grouping

Class AllGroupHeadsCollector.GroupHead<T>

java.lang.Object

org.apache.lucene.search.grouping.AllGroupHeadsCollector.GroupHead<T>

Direct Known Subclasses:

FunctionAllGroupHeadsCollector.FunctionGroupHead

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 and Description
int	doc
T	groupValue

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	GroupHead(T groupValue, int doc)

Method Summary

Modifier and Type	Method and Description
protected abstract int	compare(int compIDX, int doc) Compares the specified document for a specified comparator against the current most relevant document.
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 Detail

groupValue

public final T groupValue

doc

public int doc

Constructor Detail

GroupHead

protected GroupHead(T groupValue,
                    int doc)

Method Detail

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