javax.persistence.criteria

Interface AbstractQuery<T>

Inhoudsopgave
  • Type Parameters:
    T - the type of the result
    All Superinterfaces:
    CommonAbstractCriteria
    All Known Subinterfaces:
    CriteriaQuery<T>, Subquery<T>

    public interface AbstractQuery<T>
extends CommonAbstractCriteria
    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 Detail

      • from

        <X> 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.
        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<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(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<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

      • getRoots

        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

      • getGroupList

        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

        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

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Document heeft de 11/06/2005 gemaakt, de laatste keer de 18/08/2025 gewijzigd
Bron van het afgedrukte document:https://www.gaudry.be/nl/java-api-javaee-rf-javax/persistence/criteria/AbstractQuery.html

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Referenties

  1. Bekijk - html-document Taal van het document:fr Manuel PHP : https://docs.oracle.com, AbstractQuery (Java(TM) EE 7 Specification APIs)

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