org.apache.cayenne.query

Class FluentSelect<T>

java.lang.Object

org.apache.cayenne.query.CacheableQuery

org.apache.cayenne.query.AbstractQuery

org.apache.cayenne.query.FluentSelect<T>

All Implemented Interfaces:

Serializable, Query, Select<T>

Direct Known Subclasses:

ColumnSelect, ObjectSelect

public abstract class FluentSelect<T>
extends AbstractQuery
implements Select<T>

Base class for ObjectSelect and ColumnSelect

Since:

4.0

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected String	dbEntityName
protected String	entityName
protected Class<?>	entityType
protected Expression	having
protected Collection<Ordering>	orderings
protected Expression	where

Fields inherited from class org.apache.cayenne.query.AbstractQuery

root

Fields inherited from class org.apache.cayenne.query.CacheableQuery

logger

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	FluentSelect()

Method Summary

Modifier and Type	Method and Description
ResultBatchIterator<T>	batchIterator(ObjectContext context, int size) Creates a ResultBatchIterator based on the provided context and batch size.
SQLAction	createSQLAction(SQLActionVisitor visitor) A callback method invoked by Cayenne during the final execution phase of the query run.
Collection<Property<?>>	getColumns()
String	getDbEntityName()
String	getEntityName()
Class<?>	getEntityType()
Expression	getHaving() Returns a HAVING clause Expression of this query.
int	getLimit()
int	getOffset()
Collection<Ordering>	getOrderings()
int	getPageSize()
PrefetchTreeNode	getPrefetches()
int	getQueryTimeout()
int	getStatementFetchSize()
Expression	getWhere() Returns a WHERE clause Expression of this query.
boolean	isDistinct()
boolean	isFetchingDataRows()
void	iterate(ObjectContext context, ResultIteratorCallback<T> callback) Creates a ResultIterator based on the provided context and passes it to a callback for processing.
ResultIterator<T>	iterator(ObjectContext context) Creates a ResultIterator based on the provided context.
protected Object	resolveRoot(EntityResolver resolver)
void	route(QueryRouter router, EntityResolver resolver, Query substitutedQuery) Implements default routing mechanism relying on the EntityResolver to find DataMap based on the query root.
List<T>	select(ObjectContext context) Selects objects using provided context.
T	selectOne(ObjectContext context) Selects a single object using provided context.

Methods inherited from class org.apache.cayenne.query.AbstractQuery

getMetaData, getRoot, setRoot, toString

Methods inherited from class org.apache.cayenne.query.CacheableQuery

getBaseMetaData, getCacheGroup, getCacheStrategy, setCacheGroup, setCacheStrategy, useLocalCache, useLocalCache, useSharedCache, useSharedCache

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.cayenne.query.Select

selectFirst

Methods inherited from interface org.apache.cayenne.query.Query

getMetaData

Field Detail

entityType

protected Class<?> entityType

entityName

protected String entityName

dbEntityName

protected String dbEntityName

where

protected Expression where

having

protected Expression having

orderings

protected Collection<Ordering> orderings

Constructor Detail

FluentSelect

protected FluentSelect()

Method Detail

resolveRoot

protected Object resolveRoot(EntityResolver resolver)

getStatementFetchSize

public int getStatementFetchSize()

getQueryTimeout

public int getQueryTimeout()

Since:

4.2

getPageSize

public int getPageSize()

getLimit

public int getLimit()

getOffset

public int getOffset()

getEntityType

public Class<?> getEntityType()

getEntityName

public String getEntityName()

getDbEntityName

public String getDbEntityName()

getWhere

public Expression getWhere()

Returns a WHERE clause Expression of this query.

getHaving

public Expression getHaving()

Returns a HAVING clause Expression of this query.

getOrderings

public Collection<Ordering> getOrderings()

getPrefetches

public PrefetchTreeNode getPrefetches()

select

public List<T> select(ObjectContext context)

Description copied from interface: Select

Selects objects using provided context.

Essentially the inversion of "ObjectContext.select(Select)".

Specified by:

select in interface Select<T>

selectOne

public T selectOne(ObjectContext context)

Description copied from interface: Select

Selects a single object using provided context. The query is expected to match zero or one object. It returns null if no objects were matched. If query matched more than one object, CayenneRuntimeException is thrown.

Essentially the inversion of "ObjectContext.selectOne(Select)".

Specified by:

selectOne in interface Select<T>

iterate

public void iterate(ObjectContext context,
                    ResultIteratorCallback<T> callback)

Description copied from interface: Select

Creates a ResultIterator based on the provided context and passes it to a callback for processing. The caller does not need to worry about closing the iterator. This method takes care of it.

Essentially the inversion of "ObjectContext.iterate(Select, ResultIteratorCallback)".

Specified by:

iterate in interface Select<T>

iterator

public ResultIterator<T> iterator(ObjectContext context)

Description copied from interface: Select

Creates a ResultIterator based on the provided context. It is usually backed by an open result set and is useful for processing of large data sets, preserving a constant memory footprint. The caller must wrap iteration in try/finally (or try-with-resources for Java 1.7 and higher) and close the ResultIterator explicitly. Or use Select.iterate(ObjectContext, ResultIteratorCallback) as an alternative.

Essentially the inversion of "ObjectContext.iterator(Select)".

Specified by:

iterator in interface Select<T>

batchIterator

public ResultBatchIterator<T> batchIterator(ObjectContext context,
                                            int size)

Description copied from interface: Select

Creates a ResultBatchIterator based on the provided context and batch size. It is usually backed by an open result set and is useful for processing of large data sets, preserving a constant memory footprint. The caller must wrap iteration in try/finally (or try-with-resources for Java 1.7 and higher) and close the ResultBatchIterator explicitly.

Specified by:

batchIterator in interface Select<T>

createSQLAction

public SQLAction createSQLAction(SQLActionVisitor visitor)

Description copied from interface: Query

A callback method invoked by Cayenne during the final execution phase of the query run. A concrete query implementation is given a chance to decide how it should be handled. Implementors can pick an appropriate method of the SQLActionVisitor to handle itself, create a custom SQLAction of its own, or substitute itself with another query that should be used for SQLAction construction.

Specified by:

createSQLAction in interface Query

Specified by:

createSQLAction in class AbstractQuery

route

public void route(QueryRouter router,
                  EntityResolver resolver,
                  Query substitutedQuery)

Description copied from class: AbstractQuery

Implements default routing mechanism relying on the EntityResolver to find DataMap based on the query root. This mechanism should be sufficient for most queries that "know" their root.

Specified by:

route in interface Query

Overrides:

route in class AbstractQuery

isFetchingDataRows

public boolean isFetchingDataRows()

getColumns

public Collection<Property<?>> getColumns()

Since:

4.2

isDistinct

public boolean isDistinct()

Since:

4.2