nz.co.testamation.hibernate.HibernateEntityTemplate.java Source code

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Here is the source code for nz.co.testamation.hibernate.HibernateEntityTemplate.java

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/*
 * Copyright 2016 Ratha Long
 *
 * 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 nz.co.testamation.hibernate;

import com.google.common.base.Predicate;
import com.google.common.collect.Iterables;
import nz.co.testamation.common.util.ReflectionUtil;
import nz.co.testamation.core.waiting.Task;
import nz.co.testamation.core.waiting.WaitFor;
import org.apache.commons.lang3.reflect.FieldUtils;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.springframework.orm.hibernate4.HibernateCallback;
import org.springframework.orm.hibernate4.HibernateTemplate;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Id;
import java.io.Serializable;
import java.lang.reflect.Field;

public class HibernateEntityTemplate {

    private final SessionFactory sessionFactory;

    private final EntityManagerFactory entityManagerFactory;

    public HibernateEntityTemplate(SessionFactory sessionFactory, EntityManagerFactory entityManagerFactory) {
        this.sessionFactory = sessionFactory;
        this.entityManagerFactory = entityManagerFactory;
    }

    public interface Work<T> {
        T execute(Session session);
    }

    public interface WorkNoResult {
        void execute(Session session);
    }

    public interface EntityWork {
        void execute(EntityManager entityManager);
    }

    public void doWithNewEntity(EntityWork work) {
        EntityManager entityManager = entityManagerFactory.createEntityManager();
        work.execute(entityManager);
        entityManager.close();
    }

    public <T> T doInHibernate(final Work<T> work) {
        return new HibernateTemplate(sessionFactory).execute(new HibernateCallback<T>() {
            @Override
            public T doInHibernate(Session session) throws HibernateException {
                Transaction transaction = session.beginTransaction();
                T result = work.execute(session);
                session.flush();
                transaction.commit();
                return result;
            }
        });
    }

    public void doInHibernateNoResult(final WorkNoResult work) {
        new HibernateTemplate(sessionFactory).execute(new HibernateCallback<Object>() {
            @Override
            public Object doInHibernate(Session session) throws HibernateException {
                Transaction transaction = session.beginTransaction();
                work.execute(session);
                session.flush();
                transaction.commit();
                return null;
            }
        });
    }

    public <T> void waitForInHibernate(final Work<T> work, Predicate<T> predicate) {
        new WaitFor<>(predicate).when(new Task<T>() {
            @Override
            public T execute() {
                return doInHibernate(work);
            }
        }).run();
    }

    public <T> T reload(Session session, T obj) {
        Field field = Iterables.getOnlyElement(
                Iterables.filter(FieldUtils.getAllFieldsList(obj.getClass()), new Predicate<Field>() {
                    @Override
                    public boolean apply(Field field) {
                        return field.getAnnotation(Id.class) != null;
                    }
                }));

        return (T) session.load(obj.getClass(),
                ReflectionUtil.getFieldValue(obj, field.getName(), Serializable.class));
    }
}