Package com.googlecode.cqengine.index.suffix

Class SuffixTreeIndex<A extends CharSequence,O>

java.lang.Object

com.googlecode.cqengine.index.support.AbstractAttributeIndex<A,O>

com.googlecode.cqengine.index.suffix.SuffixTreeIndex<A,O>

All Implemented Interfaces:

ModificationListener<O>, AttributeIndex<A,O>, Index<O>, OnHeapTypeIndex

public class SuffixTreeIndex<A extends CharSequence,O>
extends AbstractAttributeIndex<A,O>
implements OnHeapTypeIndex

An index backed by a ConcurrentSuffixTree.

Supports query types:

• Equal
• StringEndsWith
• StringContains

Author:

Niall Gallagher

Field Summary

Fields inherited from class com.googlecode.cqengine.index.support.AbstractAttributeIndex

attribute, supportedQueries

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	SuffixTreeIndex(Attribute<O,A> attribute)	Package-private constructor, used by static factory methods.
protected	SuffixTreeIndex(Attribute<O,A> attribute, com.googlecode.concurrenttrees.radix.node.NodeFactory nodeFactory)	Package-private constructor, used by static factory methods.

Method Summary

Modifier and Type	Method	Description
boolean	addAll(ObjectSet<O> objectSet, QueryOptions queryOptions)	Notifies the listener that the specified objects are being added to the collection, and so it can take action and update its internal data structures.
void	clear(QueryOptions queryOptions)	Notifies the listener that all objects have been removed from the collection, and so it can take action and update its internal data structures.
StoredResultSet<O>	createValueSet()
void	destroy(QueryOptions queryOptions)	This is a no-op for this type of index.
Index<O>	getEffectiveIndex()	Returns the effective index, which Persistence objects will use to determine the identity of the index making persistence requests.
void	init(ObjectStore<O> objectStore, QueryOptions queryOptions)	Notifies the listener that the given ObjectStore has just been created.
boolean	isMutable()	Indicates if objects can be added to or removed from the index after the index has been built.
boolean	isQuantized()	Indicates if the index is quantized, using a Quantizer.
static <A extends CharSequence,O> SuffixTreeIndex<A,O>	onAttribute(Attribute<O,A> attribute)	Creates a new SuffixTreeIndex on the specified attribute.
static <A extends CharSequence,O> SuffixTreeIndex<A,O>	onAttributeUsingNodeFactory(Attribute<O,A> attribute, com.googlecode.concurrenttrees.radix.node.NodeFactory nodeFactory)	Creates a new SuffixTreeIndex on the specified attribute.
boolean	removeAll(ObjectSet<O> objectSet, QueryOptions queryOptions)	Notifies the listener that the specified objects are being removed from the collection, and so it can take action and update its internal data structures.
ResultSet<O>	retrieve(Query<O> query, QueryOptions queryOptions)	Returns a ResultSet which when iterated will return objects from the index matching the query supplied.
protected ResultSet<O>	retrieveEqual(Equal<O,A> equal, QueryOptions queryOptions, com.googlecode.concurrenttrees.suffix.SuffixTree<StoredResultSet<O>> tree)
protected ResultSet<O>	retrieveIn(In<O,A> in, QueryOptions queryOptions, com.googlecode.concurrenttrees.suffix.SuffixTree<StoredResultSet<O>> tree)

Methods inherited from class com.googlecode.cqengine.index.support.AbstractAttributeIndex

equals, getAttribute, hashCode, supportsQuery

Methods inherited from class java.lang.Object

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

Constructor Detail

SuffixTreeIndex

protected SuffixTreeIndex(Attribute<O,A> attribute)

Package-private constructor, used by static factory methods.

SuffixTreeIndex

protected SuffixTreeIndex(Attribute<O,A> attribute,
                          com.googlecode.concurrenttrees.radix.node.NodeFactory nodeFactory)

Package-private constructor, used by static factory methods.

Method Detail

isMutable

public boolean isMutable()

Description copied from interface: Index

Indicates if objects can be added to or removed from the index after the index has been built.

Specified by:

isMutable in interface Index<A extends CharSequence>

Returns:

True if objects can be added to or removed from the index after the index has been built, false if the index cannot be modified after it is built

isQuantized

public boolean isQuantized()

Description copied from interface: Index

Indicates if the index is quantized, using a Quantizer.

Specified by:

isQuantized in interface Index<A extends CharSequence>

Returns:

True if the index is quantized, false if not.

getEffectiveIndex

public Index<O> getEffectiveIndex()

Description copied from interface: Index

Returns the effective index, which Persistence objects will use to determine the identity of the index making persistence requests. Most Index implementations will typically return a reference to themselves ('this'). However in advanced cases when one index delegates to another, the implementation of the wrapping index will create a subclass the delegate index, and override this method in the delegate index so that when the delegate index interacts with the persistence, it will identify itself as the outer or "effective" index.

Specified by:

getEffectiveIndex in interface Index<A extends CharSequence>

Returns:

The effective index, in the case that this index is wrapped by another index.

retrieve

public ResultSet<O> retrieve(Query<O> query,
                             QueryOptions queryOptions)

Description copied from interface: Index

Returns a ResultSet which when iterated will return objects from the index matching the query supplied.

Usually ResultSets are lazy which means that they don't actually do any work, or encapsulate or materialize matching objects, but rather they encapsulate logic to fetch matching objects from the index on-the-fly as the application iterates through the ResultSet.

Specified by:

retrieve in interface Index<A extends CharSequence>

Parameters:

query - An object which specifies some restriction on an attribute of an object

queryOptions - Optional parameters for the query

Returns:

A set of objects with attributes matching the restriction imposed by the query

See Also:

Index.supportsQuery(Query, QueryOptions)

retrieveIn

protected ResultSet<O> retrieveIn(In<O,A> in,
                                  QueryOptions queryOptions,
                                  com.googlecode.concurrenttrees.suffix.SuffixTree<StoredResultSet<O>> tree)

retrieveEqual

protected ResultSet<O> retrieveEqual(Equal<O,A> equal,
                                     QueryOptions queryOptions,
                                     com.googlecode.concurrenttrees.suffix.SuffixTree<StoredResultSet<O>> tree)

createValueSet

public StoredResultSet<O> createValueSet()

Returns:

A StoredSetBasedResultSet based on a set backed by ConcurrentHashMap, as created via Collections.newSetFromMap(java.util.Map)

addAll

public boolean addAll(ObjectSet<O> objectSet,
                      QueryOptions queryOptions)

Notifies the listener that the specified objects are being added to the collection, and so it can take action and update its internal data structures.

Specified by:

addAll in interface ModificationListener<A extends CharSequence>

Parameters:

objectSet - The objects being added

queryOptions - Optional parameters for the update

removeAll

public boolean removeAll(ObjectSet<O> objectSet,
                         QueryOptions queryOptions)

Notifies the listener that the specified objects are being removed from the collection, and so it can take action and update its internal data structures.

Specified by:

removeAll in interface ModificationListener<A extends CharSequence>

Parameters:

objectSet - The objects being removed

queryOptions - Optional parameters for the update

init

public void init(ObjectStore<O> objectStore,
                 QueryOptions queryOptions)

Notifies the listener that the given ObjectStore has just been created.

Specified by:

init in interface ModificationListener<A extends CharSequence>

Parameters:

objectStore - The ObjectStore which persists objects

queryOptions - Optional parameters for the update

destroy

public void destroy(QueryOptions queryOptions)

This is a no-op for this type of index.

Specified by:

destroy in interface ModificationListener<A extends CharSequence>

Parameters:

queryOptions - Optional parameters for the update

clear

public void clear(QueryOptions queryOptions)

Notifies the listener that all objects have been removed from the collection, and so it can take action and update its internal data structures.

Specified by:

clear in interface ModificationListener<A extends CharSequence>

Parameters:

queryOptions - Optional parameters for the update

onAttribute

public static <A extends CharSequence,O> SuffixTreeIndex<A,O> onAttribute(Attribute<O,A> attribute)

Creates a new SuffixTreeIndex on the specified attribute.

Type Parameters:

O - The type of the object containing the attribute

Parameters:

attribute - The attribute on which the index will be built

Returns:

A SuffixTreeIndex on this attribute

onAttributeUsingNodeFactory

public static <A extends CharSequence,O> SuffixTreeIndex<A,O> onAttributeUsingNodeFactory(Attribute<O,A> attribute,
                                                                                                      com.googlecode.concurrenttrees.radix.node.NodeFactory nodeFactory)

Creates a new SuffixTreeIndex on the specified attribute.

Type Parameters:

O - The type of the object containing the attribute

Parameters:

attribute - The attribute on which the index will be built

nodeFactory - The NodeFactory to be used by the tree

Returns:

A SuffixTreeIndex on this attribute