907 words

javax.persistence.criteria.AbstractQuery - JPA interface

javax.persistence.criteria
Interface AbstractQuery<T>

Subinterfaces:
CriteriaQuery, Subquery
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:
JPA 2.0
AbstractQuery<T> distinct(boolean distinct)
Specify whether duplicate query results will be eliminated.
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
Since:
JPA 2.0
Root<X> from(Class<X> entityClass)
Create and add a query root corresponding to the given entity, forming a cartesian product with any existing roots.
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
Since:
JPA 2.0
Create and add a query root corresponding to the given entity, forming a cartesian product with any existing roots.
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
Since:
JPA 2.0
Return a list of the grouping expressions.
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
Since:
JPA 2.0
Return the predicate that corresponds to the restriction(s) over the grouping items, or null if no restrictions have been specified.
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
Since:
JPA 2.0
Return the predicate that corresponds to the where clause restriction(s), or null if no restrictions have been specified.
Return the predicate that corresponds to the where clause restriction(s), or null if no restrictions have been specified.
Returns:
where clause predicate
Since:
JPA 2.0
Class<T> getResultType()
Return the result type of the query or subquery.
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
Since:
JPA 2.0
Return the query roots.
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
Since:
JPA 2.0
Return the selection of the query, or null if no selection has been set.
Return the selection of the query, or null if no selection has been set.
Returns:
selection item
Since:
JPA 2.0
Specify the expressions that are used to form groups over the query results.
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
Since:
JPA 2.0
Specify the expressions that are used to form groups over the query results.
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
Since:
JPA 2.0
Specify restrictions over the groups of the query according the conjunction of the specified restriction predicates.
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
Since:
JPA 2.0
Specify a restriction over the groups of the query.
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
Since:
JPA 2.0
boolean isDistinct()
Return whether duplicate query results must be eliminated or retained.
Return whether duplicate query results must be eliminated or retained.
Returns:
boolean indicating whether duplicate query results must be eliminated
Since:
JPA 2.0
Subquery<U> subquery(Class<U> type)
Create a subquery of the query.
Create a subquery of the query.
Parameters:
type - the subquery result type
Returns:
subquery
Since:
JPA 2.0
Modify the query to restrict the query results according to the conjunction of the specified restriction predicates.
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
Since:
JPA 2.0
Modify the query to restrict the query results according to the specified boolean expression.
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
Since:
JPA 2.0

This documentation page is derived (with some adjustments) from the open source JPA 2 RI (EclipseLink)
and is available under the terms of the Eclipse Public License, v. 1.0 and Eclipse Distribution License, v. 1.0.
Object Relational Mapping (ORM) JPA 2 providers include Hibernate, EclipseLink, TopLink, OpenJPA and DataNucleus.
Object DB is not an ORM JPA implementation but an Object Database for Java with built in JPA 2 support.