Class RelationshipQuery

java.lang.Object

org.apache.cayenne.query.IndirectQuery

org.apache.cayenne.query.RelationshipQuery

All Implemented Interfaces:

Serializable, Query

public class RelationshipQuery
extends IndirectQuery

A query that selects objects related to a given object via a mapped relationship. RelationshipQuery is used by Cayenne internally to resolve relationships, and is rarely executed by the application directly, although this of course is possible too.

Since:

1.2

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected ArcProperty	arc
protected QueryMetadata	metadata
protected EntityResolver	metadataResolver
protected ObjectId	objectId
protected boolean	refreshing
protected String	relationshipName
protected int	statementFetchSize

Fields inherited from class IndirectQuery

dataMap, lastResolver, name, replacementQuery

Modifier and Type	Field	Description
protected DataMap	dataMap
protected EntityResolver	lastResolver
protected String	name
protected Query	replacementQuery

Constructor Summary

Constructors

Constructor	Description
RelationshipQuery(ObjectId objectID, String relationshipName)	Creates a RelationshipQuery.
RelationshipQuery(ObjectId objectID, String relationshipName, boolean refreshing)	Creates a RelationshipQuery.

Method Summary

Modifier and Type	Method	Description
protected Query	createReplacementQuery(EntityResolver resolver)	Creates a substitute query.
QueryMetadata	getMetaData(EntityResolver resolver)	Returns query metadata object.
ObjectId	getObjectId()
ObjRelationship	getRelationship(EntityResolver resolver)	Returns a non-null relationship object for this query.
String	getRelationshipName()
int	getStatementFetchSize()
boolean	isRefreshing()
void	setStatementFetchSize(int size)	Sets statement's fetch size (0 for no default size)
String	toString()	Overrides toString() outputting a short string with query class and relationship name.

Methods inherited from class IndirectQuery

createSQLAction, getReplacementQuery, route

Modifier and Type	Method	Description
SQLAction	createSQLAction(SQLActionVisitor visitor)	Throws an exception as indirect query should not be executed directly.
protected Query	getReplacementQuery(EntityResolver resolver)	Returns a replacement query, creating it on demand and caching it for reuse.
void	route(QueryRouter router, EntityResolver resolver, Query substitutedQuery)	Delegates routing to a replacement query.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

objectId

protected ObjectId objectId

relationshipName

protected String relationshipName

refreshing

protected boolean refreshing

statementFetchSize

protected int statementFetchSize

metadataResolver

protected transient EntityResolver metadataResolver

metadata

protected transient QueryMetadata metadata

arc

protected transient ArcProperty arc

Constructor Details

RelationshipQuery

public RelationshipQuery(ObjectId objectID,
 String relationshipName)

Creates a RelationshipQuery. Same as new RelationshipQuery(objectID, relationshipName, true).

Parameters:

objectID - ObjectId of a root object of the relationship.

relationshipName - The name of the relationship.

RelationshipQuery

public RelationshipQuery(ObjectId objectID,
 String relationshipName,
 boolean refreshing)

Creates a RelationshipQuery.

Parameters:

objectID - ObjectId of a root object of the relationship.

relationshipName - The name of the relationship.

refreshing - whether objects should be refreshed

Method Details

getMetaData

public QueryMetadata getMetaData(EntityResolver resolver)

Returns query metadata object.

Specified by:

getMetaData in interface Query

Overrides:

getMetaData in class IndirectQuery

getObjectId

public ObjectId getObjectId()

isRefreshing

public boolean isRefreshing()

getRelationshipName

public String getRelationshipName()

createReplacementQuery

protected Query createReplacementQuery(EntityResolver resolver)

Description copied from class: IndirectQuery

Creates a substitute query. An implementor is free to provide an arbitrary replacement query.

Specified by:

createReplacementQuery in class IndirectQuery

getRelationship

public ObjRelationship getRelationship(EntityResolver resolver)

Returns a non-null relationship object for this query.

setStatementFetchSize

public void setStatementFetchSize(int size)

Sets statement's fetch size (0 for no default size)

Since:

3.0

getStatementFetchSize

public int getStatementFetchSize()

Returns:

statement's fetch size

Since:

3.0

toString

public String toString()

Overrides toString() outputting a short string with query class and relationship name.

Overrides:

toString in class Object