com.blazebit.persistence.criteria.BlazeJoin Maven / Gradle / Ivy
/*
* Copyright 2014 - 2022 Blazebit.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.blazebit.persistence.criteria;
import javax.persistence.criteria.Expression;
import javax.persistence.criteria.Fetch;
import javax.persistence.criteria.Join;
import javax.persistence.criteria.Predicate;
/**
* An extended version of {@link Join}.
*
* @param the source type of the join
* @param the target type of the join
* @author Christian Beikov
* @since 1.2.0
*/
public interface BlazeJoin extends Fetch, Join, BlazeFrom {
/**
* Treats this from object as the given subtype. This will not cause a treat join but return a wrapper,
* that can be used for further joins.
*
* @param type type to be downcast to
* @param The target treat type
* @return The treated join object
*/
BlazeJoin treatAs(Class type);
/**
* Fetches this join.
*
* @return this join instance
*/
BlazeJoin fetch();
/**
* Whether this join is marked to also be fetched.
*
* @return true if it should be fetched, false otherwise
*/
boolean isFetch();
/* Compatibility for JPA 2.1 */
/**
* Modify the join to restrict the result according to the
* specified ON condition. Replaces the previous ON condition,
* if any.
* Return the join object
*
* @param restriction a simple or compound boolean expression
* @return the modified join object
*/
BlazeJoin on(Expression restriction);
/**
* Modify the join to restrict the result according to the
* specified ON condition. Replaces the previous ON condition,
* if any.
* Return the join object
*
* @param restrictions zero or more restriction predicates
* @return the modified join object
*/
BlazeJoin on(Predicate... restrictions);
/**
* Return the predicate that corresponds to the ON
* restriction(s) on the join, or null if no ON condition
* has been specified.
*
* @return the ON restriction predicate
*/
Predicate getOn();
}