com.autobizlogic.abl.data.hibernate.HibPersistentBeanFactory.java Source code

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Here is the source code for com.autobizlogic.abl.data.hibernate.HibPersistentBeanFactory.java

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package com.autobizlogic.abl.data.hibernate;

import java.io.Serializable;
import java.util.Map;

import org.hibernate.EntityMode;
import org.hibernate.Session;
import org.hibernate.engine.SessionImplementor;
import org.hibernate.impl.SessionFactoryImpl;
import org.hibernate.persister.entity.EntityPersister;

import com.autobizlogic.abl.data.PersistentBean;
import com.autobizlogic.abl.metadata.hibernate.HibMetaEntity;
import com.autobizlogic.abl.util.ClassNameUtil;

/**
 * The class responsible for creating instances of HibPersistentBean and HibPersistentBeanCopy.
 */
public class HibPersistentBeanFactory {

    private Session session;

    private HibPersistentBeanFactory(Session session) {
        this.session = session;
    }

    /**
     * Get an instance for the given session.
     */
    public static HibPersistentBeanFactory getInstance(Session session) {
        return new HibPersistentBeanFactory(session);
    }

    /**
     * Create a PersistentBean from a Pojo or Map entity.
     */
    public PersistentBean createPersistentBeanFromObject(Object bean, EntityPersister ep) {
        if (bean == null)
            return null;
        if (bean instanceof PersistentBean)
            throw new RuntimeException("Cannot create a PersistentBean from a PersistentBean: " + bean);
        if (!(bean instanceof Map)) {
            Class<?> epCls = ep.getMappedClass(EntityMode.POJO);
            Class<?> beanCls = bean.getClass();
            if (!epCls.isAssignableFrom(beanCls))
                throw new RuntimeException("Bean is of wrong type for the given persister: " + beanCls.getName()
                        + " vs " + epCls.getName());
        }
        Serializable pk;
        try {
            pk = ep.getIdentifier(bean, (SessionImplementor) session);
        } catch (Exception ex) {
            throw new RuntimeException(ex);
        }
        return new HibPersistentBean(bean, pk, ep, session);
    }

    /**
     * Make a shallow copy of the given Pojo or Map bean. 
     * The resulting PersistentBean will contain a copy
     * of all the attributes and single-valued relationships. Access to the collections will
     * be deferred to the original bean passed here.
     */
    public static PersistentBean createPersistentBeanCopyFromEntity(PersistentBean bean, EntityPersister ep) {
        if (bean == null)
            return null;
        return new HibPersistentBeanCopy(bean, bean.getPk(), ep);
    }

    /**
     * Create a PersistentBean from a bean (either Pojo or Map).
     * @param bean The bean
     * @param entityName Required if the bean is a Map
     * @param session The Hibernate session
     * @return The newly minted PersistentBean
     */
    public PersistentBean createPersistentBeanFromEntity(Object bean, String entityName) {
        if (bean instanceof Map && entityName == null)
            throw new RuntimeException("Cannot create a PersistentBean from a Map without an entity name");
        if (!(bean instanceof Map) && entityName == null)
            entityName = ClassNameUtil.getEntityNameForBean(bean);
        EntityPersister ep = ((SessionFactoryImpl) session.getSessionFactory()).getEntityPersister(entityName);
        return HibPersistentBeanFactory.getInstance(session).createPersistentBeanFromObject(bean, ep);
    }

    /**
     * Create a PersistentBean from an entity (either Pojo or Map).
     * This only works with Hibernate-created entities, not brand-new Pojo or Map objects
     * that have not yet been saved.
     * @param entity The entity in question, can be either a Pojo or a Map
     * @return A new PersistentBean
     */
    public PersistentBean createPersistentBeanFromEntity(Object entity) {
        String entityName = session.getEntityName(entity);
        return createPersistentBeanFromEntity(entity, entityName);
    }

    /**
     * Make a shallow copy of the given Pojo or Map object. 
     * The resulting PersistentBean will contain a copy
     * of all the attributes and single-valued relationships. Access to the collections will
     * be deferred to the original bean passed here.
     */
    public PersistentBean createPersistentBeanCopyFromObject(Object bean, EntityPersister ep) {
        if (bean == null)
            return null;
        try {
            Serializable pk = ep.getIdentifier(bean, (SessionImplementor) session);
            return new HibPersistentBeanCopy(bean, pk, ep);
        } catch (Exception ex) {
            ex.printStackTrace();
            return null;
        }
    }

    /**
     * Make a shallow copy of the given Pojo or Map bean. The resulting PersistentBean will contain 
     * a copy of all the attributes and single-valued relationships. Access to the collections will
     * be deferred to the original Pojo or Map bean passed herein.
     */
    public static PersistentBean createPersistentBeanCopyFromState(Object[] state, Object entity,
            EntityPersister ep, Session session) {

        Serializable pk = ep.getIdentifier(entity, (SessionImplementor) session);
        return new HibPersistentBeanCopy(state, entity, pk, ep, session);
    }

    /**
     * Make a shallow copy of the given PersistentBean. Note that if the bean passed in is
     * already a copy, it will be returned as is.
     */
    public static PersistentBean copyPersistentBean(PersistentBean pbean) {

        // If it's already a copy, there is really no point in copying it again.
        if (pbean instanceof HibPersistentBeanCopy)
            return pbean;

        HibMetaEntity metaEntity = (HibMetaEntity) pbean.getMetaEntity();
        return createPersistentBeanCopyFromEntity(pbean, metaEntity.getEntityPersister());
    }
}

/*
 * The contents of this file are subject to the Automated Business Logic Public License Version 1.0 (the "License"),
 * which is derived from the Mozilla Public License version 1.1. You may not use this file except in compliance with the License. 
 * You may obtain a copy of the License at http://www.automatedbusinesslogic.com/license/public-license
 *
 * Software distributed under the License is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, 
 * either express or implied. See the License for the specific language governing rights and limitations under the License.
 */