com.mysema.query.collections

Class AbstractCollQuery<Q extends AbstractCollQuery<Q>>

java.lang.Object

com.mysema.query.support.QueryBase<Q>

com.mysema.query.support.ProjectableQuery<Q>

com.mysema.query.collections.AbstractCollQuery<Q>

All Implemented Interfaces:

FilteredClause<Q>, Projectable, SimpleQuery<Q>

Direct Known Subclasses:

CollQuery

public abstract class AbstractCollQuery<Q extends AbstractCollQuery<Q>>
extends ProjectableQuery<Q>
implements SimpleQuery<Q>

AbstractCollQuery provides a base class for Collection query implementations. Extend it like this

 public class MyType extends AbstractColQuery<MyType>{
   ...
 }
 

Author:

tiwe

See Also:

CollQuery

Field Summary

Fields inherited from class com.mysema.query.support.QueryBase

queryMixin

Constructor Summary

Constructors

Constructor and Description
AbstractCollQuery(QueryMetadata metadata, QueryEngine queryEngine)

Method Summary

Methods

Modifier and Type	Method and Description
<A> Q	bind(Path<A> entity, Iterable<? extends A> col) Bind the given collection to an already existing query source
long	count() return the amount of matched rows
boolean	exists()
<A> Q	from(Path<A> entity, Iterable<? extends A> col) Add a query source
abstract QueryMetadata	getMetadata()
protected QueryEngine	getQueryEngine()
<P> Q	innerJoin(MapExpression<?,P> target, Path<P> alias) Define an inner join from the Map typed path to the alias
<P> Q	innerJoin(Path<? extends Collection<P>> target, Path<P> alias) Define an inner join from the Collection typed path to the alias
com.mysema.commons.lang.CloseableIterator<Tuple>	iterate(Expression<?>... args) iterate over the results for the given projection
<RT> com.mysema.commons.lang.CloseableIterator<RT>	iterate(Expression<RT> projection) iterate over the results for the given projection
<P> Q	leftJoin(MapExpression<?,P> target, Path<P> alias) Define a left join from the Map typed path to the alias
<P> Q	leftJoin(Path<? extends Collection<P>> target, Path<P> alias) Define a left join from the Collection typed path to the alias
List<Tuple>	list(Expression<?>... args) list the results for the given projection An empty list is returned for no results.
<RT> List<RT>	list(Expression<RT> projection) list the results for the given projection An empty list is returned for no results.
SearchResults<Tuple>	listResults(Expression<?>... args) list the results for the given projection
<RT> SearchResults<RT>	listResults(Expression<RT> projection) list the results for the given projection
Tuple	uniqueResult(Expression<?>... args) return a unique result for the given projection or null if no result is found
<RT> RT	uniqueResult(Expression<RT> expr) return a unique result for the given projection or null if no result is found

Methods inherited from class com.mysema.query.support.ProjectableQuery

map, notExists, singleResult, singleResult, transform, uniqueResult

Methods inherited from class com.mysema.query.support.QueryBase

distinct, equals, groupBy, groupBy, hashCode, having, having, limit, offset, orderBy, orderBy, restrict, set, toString, where, where

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.mysema.query.SimpleQuery

distinct, limit, offset, orderBy, restrict, set

Methods inherited from interface com.mysema.query.FilteredClause

where

Constructor Detail

AbstractCollQuery

public AbstractCollQuery(QueryMetadata metadata,
                 QueryEngine queryEngine)

Method Detail

count

public long count()

Description copied from interface: Projectable

return the amount of matched rows

Specified by:

count in interface Projectable

exists

public boolean exists()

Specified by:

exists in interface Projectable

Returns:

true, if rows matching the given criteria exist, otherwise false

from

public <A> Q from(Path<A> entity,
         Iterable<? extends A> col)

Add a query source

Type Parameters:

A -

Parameters:

entity - Path for the source

col - content of the source

Returns:

bind

public <A> Q bind(Path<A> entity,
         Iterable<? extends A> col)

Bind the given collection to an already existing query source

Type Parameters:

A -

Parameters:

entity - Path for the source

col - content of the source

Returns:

getMetadata

public abstract QueryMetadata getMetadata()

getQueryEngine

protected QueryEngine getQueryEngine()

innerJoin

public <P> Q innerJoin(Path<? extends Collection<P>> target,
              Path<P> alias)

Define an inner join from the Collection typed path to the alias

Type Parameters:

P -

Parameters:

collectionPath -

alias -

Returns:

innerJoin

public <P> Q innerJoin(MapExpression<?,P> target,
              Path<P> alias)

Define an inner join from the Map typed path to the alias

Type Parameters:

P -

Parameters:

mapPath -

alias -

Returns:

leftJoin

public <P> Q leftJoin(Path<? extends Collection<P>> target,
             Path<P> alias)

Define a left join from the Collection typed path to the alias

Type Parameters:

P -

Parameters:

collectionPath -

alias -

Returns:

leftJoin

public <P> Q leftJoin(MapExpression<?,P> target,
             Path<P> alias)

Define a left join from the Map typed path to the alias

Type Parameters:

P -

Parameters:

mapPath -

alias -

Returns:

iterate

public com.mysema.commons.lang.CloseableIterator<Tuple> iterate(Expression<?>... args)

Description copied from interface: Projectable

iterate over the results for the given projection

Specified by:

iterate in interface Projectable

Returns:

iterate

public <RT> com.mysema.commons.lang.CloseableIterator<RT> iterate(Expression<RT> projection)

Description copied from interface: Projectable

iterate over the results for the given projection

Specified by:

iterate in interface Projectable

Type Parameters:

RT - generic type of the Iterator

Returns:

an Iterator over the projection

list

public List<Tuple> list(Expression<?>... args)

Description copied from interface: Projectable

list the results for the given projection An empty list is returned for no results.

Specified by:

list in interface Projectable

Overrides:

list in class ProjectableQuery<Q extends AbstractCollQuery<Q>>

Returns:

list

public <RT> List<RT> list(Expression<RT> projection)

Description copied from interface: Projectable

list the results for the given projection An empty list is returned for no results.

Specified by:

list in interface Projectable

Overrides:

list in class ProjectableQuery<Q extends AbstractCollQuery<Q>>

Type Parameters:

RT - generic type of the List

Returns:

a List over the projection

listResults

public SearchResults<Tuple> listResults(Expression<?>... args)

Description copied from interface: Projectable

list the results for the given projection

Specified by:

listResults in interface Projectable

Returns:

listResults

public <RT> SearchResults<RT> listResults(Expression<RT> projection)

Description copied from interface: Projectable

list the results for the given projection

Specified by:

listResults in interface Projectable

Returns:

uniqueResult

public Tuple uniqueResult(Expression<?>... args)

Description copied from interface: Projectable

return a unique result for the given projection or null if no result is found

There is some ambiguity for missing results and null valued results, for disambiguation use the list or iterate methods instead.

Specified by:

uniqueResult in interface Projectable

Returns:

uniqueResult

public <RT> RT uniqueResult(Expression<RT> expr)

Description copied from interface: Projectable

return a unique result for the given projection or null if no result is found

There is some ambiguity for missing results and null valued results, for disambiguation use the list or iterate methods instead.

Specified by:

uniqueResult in interface Projectable

Type Parameters:

RT - return type

Returns:

the result or null for an empty result