public class

MultiPassIndexSplitter

extends Object
java.lang.Object
   ↳ org.apache.lucene.index.MultiPassIndexSplitter

Class Overview

This tool splits input index into multiple equal parts. The method employed here uses addIndexes(IndexReader[]) where the input data comes from the input index with artificially applied deletes to the document id-s that fall outside the selected partition.

Note 1: Deletes are only applied to a buffered list of deleted docs and don't affect the source index - this tool works also with read-only indexes.

Note 2: the disadvantage of this tool is that source index needs to be read as many times as there are parts to be created, hence the name of this tool.

NOTE: this tool is unaware of documents added atomically via addDocuments(Collection) or updateDocuments(Term, Collection), which means it can easily break up such document groups.

Summary

Nested Classes
class MultiPassIndexSplitter.FakeDeleteIndexReader This class pretends that it can write deletions to the underlying index. 
Public Constructors
MultiPassIndexSplitter()
Public Methods
static void main(String[] args)
void split(IndexReader input, Directory[] outputs, boolean seq)
Split source index into multiple parts.
[Expand]
Inherited Methods
From class java.lang.Object

Public Constructors

public MultiPassIndexSplitter ()

Public Methods

public static void main (String[] args)

Throws
Exception

public void split (IndexReader input, Directory[] outputs, boolean seq)

Split source index into multiple parts.

Parameters
input source index, can be read-only, can have deletions, can have multiple segments (or multiple readers).
outputs list of directories where the output parts will be stored.
seq if true, then the source index will be split into equal increasing ranges of document id-s. If false, source document id-s will be assigned in a deterministic round-robin fashion to one of the output splits.
Throws
IOException