com.lucidworks.search.dsl.request.query

Class GraphQuery

java.lang.Object

com.lucidworks.search.dsl.DslBase

com.lucidworks.search.dsl.request.DslCloneable

com.lucidworks.search.dsl.request.query.Query

com.lucidworks.search.dsl.request.query.GraphQuery

public class GraphQuery
extends Query

A query to traverse graph-like relationships in indexed data. Use of this query assumes your data is setup to represent a directed graph. Each document represents a node in the graph and its connecting edges: the "from" field holds an identifier for the node itself, with outgoing edges represented by the node IDs held in the "to" field. The starting points or seeds for the traversal are identified by the result set of the provided subquery. The result set of this query contains all documents/nodes reachable via graph traversal from the provided seeds.

Field Summary

Fields

Modifier and Type	Field and Description
static String	TYPE

Constructor Summary

Constructors

Constructor and Description
GraphQuery(String from, String to, Query query)

Method Summary

Modifier and Type	Method and Description
GraphQuery	clone()
List<Query>	getChildQueries() Returns all the children of the query in question.
String	getFrom()
Query	getQuery()
String	getTo()
boolean	isEmptyQuery()
boolean	removeChildQuery(Query toRemove) Remove 'toRemove', if 'toRemove' is currently a child of this Query object.
boolean	replaceChildQuery(Query toReplace, Query replacement) Swap 'replacement' in as a replacement, if 'toReplace' is currently a child of this Query object.

Methods inherited from class com.lucidworks.search.dsl.request.DslCloneable

clone, deepClone

Methods inherited from class com.lucidworks.search.dsl.DslBase

equals, hashCode, toString

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Field Detail

TYPE

public static final String TYPE

See Also:

Constant Field Values

Constructor Detail

GraphQuery

public GraphQuery(String from,
                  String to,
                  Query query)

Method Detail

getTo

public String getTo()

Returns:

the field name that holds each document's outgoing edges. The values in this field should match values held by the "from" field in other documents.

getFrom

public String getFrom()

Returns:

the field name that holds an identifier for each document/node in the graph.

getQuery

public Query getQuery()

Returns:

a query whose result set documents are used as seeds for the graph traversal.

getChildQueries

public List<Query> getChildQueries()

Description copied from class: Query

Returns all the children of the query in question. The returned List is provided as a copy - changes made to it do not impact the originating Query object in any way.

Specified by:

getChildQueries in class Query

replaceChildQuery

public boolean replaceChildQuery(Query toReplace,
                                 Query replacement)

Description copied from class: Query

Swap 'replacement' in as a replacement, if 'toReplace' is currently a child of this Query object. Because a tree of Query objects might conceivably have repeated clauses, this method is implemented to test 'toReplace' using reference-equality instead of value-equality.

Specified by:

replaceChildQuery in class Query

Returns:

true if a replacement was made, false otherwise.

removeChildQuery

public boolean removeChildQuery(Query toRemove)

Description copied from class: Query

Remove 'toRemove', if 'toRemove' is currently a child of this Query object. Because a tree of Query objects might conceivably have repeated clauses, this method is implemented to test 'toRemove' using reference-equality instead of value-equality.

Specified by:

removeChildQuery in class Query

Returns:

true if a removal was made, false otherwise.

isEmptyQuery

public boolean isEmptyQuery()

Specified by:

isEmptyQuery in class Query

Returns:

true if this query is now essentially "empty" (doesn't affect query logic at all) and can now be removed from the query tree. This can happen, for example, if all child queries were removed and the query logic depends on having at least one child query.

clone

public GraphQuery clone()

Specified by:

clone in class Query