com.vladmihalcea.HibernateFetchStrategyTest.java Source code

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Here is the source code for com.vladmihalcea.HibernateFetchStrategyTest.java

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/*
 * Copyright 2013 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 com.vladmihalcea;

import com.vladmihalcea.hibernate.model.store.*;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.annotation.DirtiesContext;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.transaction.TransactionStatus;
import org.springframework.transaction.support.TransactionCallback;
import org.springframework.transaction.support.TransactionTemplate;

import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Root;

import static org.junit.Assert.assertNotNull;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = { "classpath:spring/applicationContext-test.xml" })
@DirtiesContext(classMode = DirtiesContext.ClassMode.AFTER_CLASS)
public class HibernateFetchStrategyTest {

    private static final Logger LOG = LoggerFactory.getLogger(HibernateFetchStrategyTest.class);

    @PersistenceContext(unitName = "persistenceUnit")
    private EntityManager entityManager;

    @Autowired
    private TransactionTemplate transactionTemplate;

    @Before
    public void beforeTest() {
        CleanDbUtil.cleanStore(transactionTemplate, entityManager);
    }

    @Test
    public void test() {

        final Long productId = transactionTemplate.execute(new TransactionCallback<Long>() {
            @Override
            public Long doInTransaction(TransactionStatus transactionStatus) {

                Company company = new Company();
                company.setName("TV Company");
                entityManager.persist(company);

                Product product = new Product("tvCode");
                product.setName("TV");
                product.setCompany(company);

                Image frontImage = new Image();
                frontImage.setName("front image");
                frontImage.setIndex(0);

                Image sideImage = new Image();
                sideImage.setName("side image");
                sideImage.setIndex(1);

                product.addImage(frontImage);
                product.addImage(sideImage);

                WarehouseProductInfo warehouseProductInfo = new WarehouseProductInfo();
                warehouseProductInfo.setQuantity(101);
                product.addWarehouse(warehouseProductInfo);

                Importer importer = new Importer();
                importer.setName("Importer");
                entityManager.persist(importer);
                product.setImporter(importer);

                entityManager.persist(product);
                return product.getId();
            }
        });
        transactionTemplate.execute(new TransactionCallback<Void>() {
            @Override
            public Void doInTransaction(TransactionStatus transactionStatus) {
                LOG.info("Fetch using find");
                Product product = entityManager.find(Product.class, productId);
                assertNotNull(product);
                return null;
            }
        });

        transactionTemplate.execute(new TransactionCallback<Void>() {
            @Override
            public Void doInTransaction(TransactionStatus transactionStatus) {
                LOG.info("Fetch using JPQL");
                Product product = entityManager
                        .createQuery("select p " + "from Product p " + "where p.id = :productId", Product.class)
                        .setParameter("productId", productId).getSingleResult();
                assertNotNull(product);
                return null;
            }
        });
        transactionTemplate.execute(new TransactionCallback<Void>() {
            @Override
            public Void doInTransaction(TransactionStatus transactionStatus) {

                LOG.info("Fetch using Criteria");

                CriteriaBuilder cb = entityManager.getCriteriaBuilder();
                CriteriaQuery<Product> cq = cb.createQuery(Product.class);
                Root<Product> productRoot = cq.from(Product.class);
                cq.where(cb.equal(productRoot.get("id"), productId));
                Product product = entityManager.createQuery(cq).getSingleResult();
                assertNotNull(product);
                return null;
            }
        });
        transactionTemplate.execute(new TransactionCallback<Void>() {
            @Override
            public Void doInTransaction(TransactionStatus transactionStatus) {
                LOG.info("Fetch using join fetch JPQL");

                Product product = product = entityManager.createQuery("select p " + "from Product p "
                        + "inner join fetch p.warehouseProductInfo " + "inner join fetch p.importer", Product.class)
                        .getSingleResult();
                assertNotNull(product);

                return null;
            }
        });
        transactionTemplate.execute(new TransactionCallback<Void>() {
            @Override
            public Void doInTransaction(TransactionStatus transactionStatus) {

                Image image = entityManager
                        .createQuery("select i " + "from Image i " + "inner join fetch i.product p "
                                + "where p.id = :productId", Image.class)
                        .setParameter("productId", productId).getResultList().get(0);
                assertNotNull(image);

                return null;
            }
        });
    }
}