/*
* Copyright 2011 the original author or authors.
*
* 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 org.springframework.data.jpa.repository.support;
import javax.annotation.PostConstruct;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import org.springframework.stereotype.Repository;
import org.springframework.util.Assert;
import com.mysema.query.dml.DeleteClause;
import com.mysema.query.dml.UpdateClause;
import com.mysema.query.jpa.JPQLQuery;
import com.mysema.query.jpa.impl.JPADeleteClause;
import com.mysema.query.jpa.impl.JPAUpdateClause;
import com.mysema.query.types.EntityPath;
import com.mysema.query.types.path.PathBuilder;
import com.mysema.query.types.path.PathBuilderFactory;
/**
* Base class for implementing repositories using QueryDsl library.
*
* @author Oliver Gierke
*/
@Repository
public abstract class QueryDslRepositorySupport {
private final PathBuilder<?> builder;
private EntityManager entityManager;
private Querydsl querydsl;
/**
* Creates a new {@link QueryDslRepositorySupport} instance for the given domain type.
*
* @param domainClass must not be {@literal null}.
*/
public QueryDslRepositorySupport(Class<?> domainClass) {
Assert.notNull(domainClass);
this.builder = new PathBuilderFactory().create(domainClass);
}
/**
* Setter to inject {@link EntityManager}.
*
* @param entityManager must not be {@literal null}
*/
@PersistenceContext
public void setEntityManager(EntityManager entityManager) {
Assert.notNull(entityManager);
this.querydsl = new Querydsl(entityManager, builder);
this.entityManager = entityManager;
}
/**
* Callback to verify configuration. Used by containers.
*/
@PostConstruct
public void validate() {
Assert.notNull(entityManager, "EntityManager must not be null!");
Assert.notNull(querydsl, "Querydsl must not be null!");
}
/**
* Returns the {@link EntityManager}.
*
* @return the entityManager
*/
protected EntityManager getEntityManager() {
return entityManager;
}
/**
* Returns a fresh {@link JPQLQuery}.
*
* @return the Querydsl {@link JPQLQuery}.
*/
protected JPQLQuery from(EntityPath<?>... paths) {
return querydsl.createQuery(paths);
}
/**
* Returns a fresh {@link DeleteClause}.
*
* @param path
* @return the Querydsl {@link DeleteClause}.
*/
protected DeleteClause<JPADeleteClause> delete(EntityPath<?> path) {
return new JPADeleteClause(entityManager, path);
}
/**
* Returns a fresh {@link UpdateClause}.
*
* @param path
* @return the Querydsl {@link UpdateClause}.
*/
protected UpdateClause<JPAUpdateClause> update(EntityPath<?> path) {
return new JPAUpdateClause(entityManager, path);
}
/**
* Returns a {@link PathBuilder} for the configured domain type.
*
* @param <T>
* @return the Querdsl {@link PathBuilder}.
*/
@SuppressWarnings("unchecked")
protected <T> PathBuilder<T> getBuilder() {
return (PathBuilder<T>) builder;
}
/**
* Returns the underlying Querydsl helper instance.
*
* @return
*/
protected Querydsl getQuerydsl() {
return this.querydsl;
}
}