org.apache.jackrabbit.oak.plugins.index.lucene

Class LuceneIndex

java.lang.Object

org.apache.jackrabbit.oak.plugins.index.lucene.LuceneIndex

All Implemented Interfaces:

QueryIndex, QueryIndex.FulltextQueryIndex

public class LuceneIndex
extends Object
implements QueryIndex.FulltextQueryIndex

Provides a QueryIndex that does lookups against a Lucene-based index

To define a lucene index on a subtree you have to add an oak:index node. Under it follows the index definition node that:

• must be of type oak:QueryIndexDefinition
• must have the type property set to lucene
• must have the async property set to async

Optionally you can add

• what subset of property types to be included in the index via the includePropertyTypes property
• a blacklist of property names: what property to be excluded from the index via the excludePropertyNames property
• the reindex flag which when set to true, triggers a full content re-index.

 
 {
     NodeBuilder index = root.child("oak:index");
     index.child("lucene")
         .setProperty("jcr:primaryType", "oak:QueryIndexDefinition", Type.NAME)
         .setProperty("type", "lucene")
         .setProperty("async", "async")
         .setProperty("reindex", "true");
 }
 
 

See Also:

QueryIndex

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.jackrabbit.oak.spi.query.QueryIndex

QueryIndex.AdvancedQueryIndex, QueryIndex.FulltextQueryIndex, QueryIndex.IndexPlan, QueryIndex.OrderEntry

Field Summary

Fields

Modifier and Type	Field and Description
static String	NATIVE_QUERY_FUNCTION

Constructor Summary

Constructors

Constructor and Description
LuceneIndex(org.apache.jackrabbit.oak.plugins.index.lucene.IndexTracker tracker, Analyzer analyzer, NodeAggregator aggregator)

Method Summary

Methods

Modifier and Type	Method and Description
double	getCost(Filter filter, NodeState root) Estimate the worst-case cost to query with the given filter.
String	getIndexName() Get the unique index name.
NodeAggregator	getNodeAggregator() Returns the NodeAggregator responsible for providing the aggregation settings or null if aggregation is not available/desired.
String	getPlan(Filter filter, NodeState root) Get the query plan for the given filter.
Cursor	query(Filter filter, NodeState root) Query the index.

Methods inherited from class java.lang.Object

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

Field Detail

NATIVE_QUERY_FUNCTION

public static final String NATIVE_QUERY_FUNCTION

See Also:

Constant Field Values

Constructor Detail

LuceneIndex

public LuceneIndex(org.apache.jackrabbit.oak.plugins.index.lucene.IndexTracker tracker,
           Analyzer analyzer,
           NodeAggregator aggregator)

Method Detail

getIndexName

public String getIndexName()

Description copied from interface: QueryIndex

Get the unique index name.

Specified by:

getIndexName in interface QueryIndex

Returns:

the index name

getCost

public double getCost(Filter filter,
             NodeState root)

Description copied from interface: QueryIndex

Estimate the worst-case cost to query with the given filter. The returned cost is a value between 1 (very fast; lookup of a unique node) and the estimated number of entries to traverse, if the cursor would be fully read, and if there could in theory be one network roundtrip or disk read operation per node (this method may return a lower number if the data is known to be fully in memory).

The returned value is supposed to be an estimate and doesn't have to be very accurate. Please note this method is called on each index whenever a query is run, so the method should be reasonably fast (not read any data itself, or at least not read too much data).

If an index implementation can not query the data, it has to return Double.MAX_VALUE.

Specified by:

getCost in interface QueryIndex

Parameters:

filter - the filter

root - root state of the current repository snapshot

Returns:

the estimated cost in number of read nodes

getPlan

public String getPlan(Filter filter,
             NodeState root)

Description copied from interface: QueryIndex

Get the query plan for the given filter. This method is called when running an EXPLAIN SELECT query, or for logging purposes. The result should be human readable.

Specified by:

getPlan in interface QueryIndex

Parameters:

filter - the filter

root - root state of the current repository snapshot

Returns:

the query plan

query

public Cursor query(Filter filter,
           NodeState root)

Description copied from interface: QueryIndex

Query the index. The returned cursor is supposed to return as few nodes as possible, but may return more nodes than necessary.

An implementation should only filter the result if it can do so easily and efficiently; the query engine will verify the data again (in memory) and check for access rights.

The method is only called if this index is used for the given query and selector, which is only the case if the given index implementation returned the lowest cost for the given filter. If the implementation returned Double.MAX_VALUE in the getCost method for the given filter, then this method is not called. If it is still called, then it is supposed to throw an exception (as it would be an internal error of the query engine).

Specified by:

query in interface QueryIndex

Parameters:

filter - the filter

root - root state of the current repository snapshot

Returns:

a cursor to iterate over the result

getNodeAggregator

public NodeAggregator getNodeAggregator()

Description copied from interface: QueryIndex.FulltextQueryIndex

Returns the NodeAggregator responsible for providing the aggregation settings or null if aggregation is not available/desired.

Specified by:

getNodeAggregator in interface QueryIndex.FulltextQueryIndex

Returns:

the node aggregator or null