javax.persistence.criteria
Interface AbstractQuery<T>

Type Parameters:

T - the type of the result

All Known Subinterfaces:

CriteriaQuery<T>, Subquery<T>

public interface AbstractQuery<T>

The AbstractQuery interface defines functionality that is common to both top-level queries and subqueries. It is not intended to be used directly in query construction.

All queries must have: a set of root entities (which may in turn own joins).

All queries may have: a conjunction of restrictions.

Since:

Java Persistence 2.0

Method Summary

AbstractQuery<T>	distinct(boolean distinct) Specify whether duplicate query results will be eliminated.
<X> Root<X>	from(java.lang.Class<X> entityClass) Create and add a query root corresponding to the given entity, forming a cartesian product with any existing roots.
<X> Root<X>	from(EntityType<X> entity) Create and add a query root corresponding to the given entity, forming a cartesian product with any existing roots.
java.util.List<Expression<?>>	getGroupList() Return a list of the grouping expressions.
Predicate	getGroupRestriction() Return the predicate that corresponds to the restriction(s) over the grouping items, or null if no restrictions have been specified.
Predicate	getRestriction() Return the predicate that corresponds to the where clause restriction(s), or null if no restrictions have been specified.
java.lang.Class<T>	getResultType() Return the result type of the query or subquery.
java.util.Set<Root<?>>	getRoots() Return the query roots.
Selection<T>	getSelection() Return the selection of the query, or null if no selection has been set.
AbstractQuery<T>	groupBy(Expression<?>... grouping) Specify the expressions that are used to form groups over the query results.
AbstractQuery<T>	groupBy(java.util.List<Expression<?>> grouping) Specify the expressions that are used to form groups over the query results.
AbstractQuery<T>	having(Expression<java.lang.Boolean> restriction) Specify a restriction over the groups of the query.
AbstractQuery<T>	having(Predicate... restrictions) Specify restrictions over the groups of the query according the conjunction of the specified restriction predicates.
boolean	isDistinct() Return whether duplicate query results must be eliminated or retained.
<U> Subquery<U>	subquery(java.lang.Class<U> type) Create a subquery of the query.
AbstractQuery<T>	where(Expression<java.lang.Boolean> restriction) Modify the query to restrict the query results according to the specified boolean expression.
AbstractQuery<T>	where(Predicate... restrictions) Modify the query to restrict the query results according to the conjunction of the specified restriction predicates.

Method Detail

from

<X> Root<X> from(java.lang.Class<X> entityClass)

Create and add a query root corresponding to the given entity, forming a cartesian product with any existing roots.

Parameters:

entityClass - the entity class

Returns:

query root corresponding to the given entity

from

<X> Root<X> from(EntityType<X> entity)

Create and add a query root corresponding to the given entity, forming a cartesian product with any existing roots.

Parameters:

entity - metamodel entity representing the entity of type X

Returns:

query root corresponding to the given entity

where

AbstractQuery<T> where(Expression<java.lang.Boolean> restriction)

Modify the query to restrict the query results according to the specified boolean expression. Replaces the previously added restriction(s), if any.

Parameters:

restriction - a simple or compound boolean expression

Returns:

the modified query

where

AbstractQuery<T> where(Predicate... restrictions)

Modify the query to restrict the query results according to the conjunction of the specified restriction predicates. Replaces the previously added restriction(s), if any. If no restrictions are specified, any previously added restrictions are simply removed.

Parameters:

restrictions - zero or more restriction predicates

Returns:

the modified query

groupBy

AbstractQuery<T> groupBy(Expression<?>... grouping)

Specify the expressions that are used to form groups over the query results. Replaces the previous specified grouping expressions, if any. If no grouping expressions are specified, any previously added grouping expressions are simply removed.

Parameters:

grouping - zero or more grouping expressions

Returns:

the modified query

groupBy

AbstractQuery<T> groupBy(java.util.List<Expression<?>> grouping)

Specify the expressions that are used to form groups over the query results. Replaces the previous specified grouping expressions, if any. If no grouping expressions are specified, any previously added grouping expressions are simply removed.

Parameters:

grouping - list of zero or more grouping expressions

Returns:

the modified query

having

AbstractQuery<T> having(Expression<java.lang.Boolean> restriction)

Specify a restriction over the groups of the query. Replaces the previous having restriction(s), if any.

Parameters:

restriction - a simple or compound boolean expression

Returns:

the modified query

having

AbstractQuery<T> having(Predicate... restrictions)

Specify restrictions over the groups of the query according the conjunction of the specified restriction predicates. Replaces the previously having added restriction(s), if any. If no restrictions are specified, any previously added restrictions are simply removed.

Parameters:

restrictions - zero or more restriction predicates

Returns:

the modified query

distinct

AbstractQuery<T> distinct(boolean distinct)

Specify whether duplicate query results will be eliminated. A true value will cause duplicates to be eliminated. A false value will cause duplicates to be retained. If distinct has not been specified, duplicate results must be retained.

Parameters:

distinct - boolean value specifying whether duplicate results must be eliminated from the query result or whether they must be retained

Returns:

the modified query

subquery

<U> Subquery<U> subquery(java.lang.Class<U> type)

Create a subquery of the query.

Parameters:

type - the subquery result type

Returns:

subquery

getRoots

java.util.Set<Root<?>> getRoots()

Return the query roots. These are the roots that have been defined for the CriteriaQuery or Subquery itself, including any subquery roots defined as a result of correlation. Returns empty set if no roots have been defined. Modifications to the set do not affect the query.

Returns:

the set of query roots

getSelection

Selection<T> getSelection()

Return the selection of the query, or null if no selection has been set.

Returns:

selection item

getRestriction

Predicate getRestriction()

Return the predicate that corresponds to the where clause restriction(s), or null if no restrictions have been specified.

Returns:

where clause predicate

getGroupList

java.util.List<Expression<?>> getGroupList()

Return a list of the grouping expressions. Returns empty list if no grouping expressions have been specified. Modifications to the list do not affect the query.

Returns:

the list of grouping expressions

getGroupRestriction

Predicate getGroupRestriction()

Return the predicate that corresponds to the restriction(s) over the grouping items, or null if no restrictions have been specified.

Returns:

having clause predicate

isDistinct

boolean isDistinct()

Return whether duplicate query results must be eliminated or retained.

Returns:

boolean indicating whether duplicate query results must be eliminated

getResultType

java.lang.Class<T> getResultType()

Return the result type of the query or subquery. If a result type was specified as an argument to the createQuery or subquery method, that type will be returned. If the query was created using the createTupleQuery method, the result type is Tuple. Otherwise, the result type is Object.

Returns:

result type