com.querydsl.jpa.QueryHandler Maven / Gradle / Ivy
/*
* Copyright 2015, The Querydsl Team (http://www.querydsl.com/team)
*
* 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.querydsl.jpa;
import javax.annotation.Nullable;
import javax.persistence.Query;
import com.mysema.commons.lang.CloseableIterator;
import com.querydsl.core.types.FactoryExpression;
/**
* {@code QueryHandle}r provides injection of provider specific functionality into the query logic
*
* @author tiwe
*
*/
public interface QueryHandler {
/**
* Return whether native queries should be created as typed queries
*
* @return whether native queries should be created as typed queries
*/
boolean createNativeQueryTyped();
/**
* Iterate the results with the optional projection
*
* @param query query
* @return iterator
*/
CloseableIterator iterate(Query query, @Nullable FactoryExpression projection);
/**
* Add the given scalar to the given native query
*
* @param query query
* @param alias alias
* @param type type
*/
void addScalar(Query query, String alias, Class type);
/**
* Add the given entity to the given native query
*
* @param query query
* @param alias alias
* @param type type
*/
void addEntity(Query query, String alias, Class type);
/**
* Transform the results of the given query using the given factory expression
*
* @param query query
* @param projection projection
* @return true, if query as been modified
*/
boolean transform(Query query, FactoryExpression projection);
/**
* Return whether entity projections need to be wrapped
*
* @return whether entity projections need to be wrapped
*/
boolean wrapEntityProjections();
}