net.sf.mmm.persistence.impl.hibernate.AbstractRevisionedDaoEnvers.java Source code

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Here is the source code for net.sf.mmm.persistence.impl.hibernate.AbstractRevisionedDaoEnvers.java

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/* Copyright (c) The m-m-m Team, Licensed under the Apache License, Version 2.0
 * http://www.apache.org/licenses/LICENSE-2.0 */
package net.sf.mmm.persistence.impl.hibernate;

import java.util.ArrayList;
import java.util.List;

import javax.inject.Inject;

import net.sf.mmm.persistence.api.PersistenceManager;
import net.sf.mmm.persistence.api.RevisionMetadata;
import net.sf.mmm.persistence.api.RevisionedDao;
import net.sf.mmm.persistence.base.jpa.AbstractJpaGenericDao;
import net.sf.mmm.util.entity.api.MutableRevisionedEntity;
import net.sf.mmm.util.entity.api.RevisionedEntity;
import net.sf.mmm.util.exception.api.ObjectNotFoundException;

import org.hibernate.envers.AuditReader;
import org.hibernate.envers.AuditReaderFactory;

/**
 * This is the abstract base-implementation of a {@link net.sf.mmm.persistence.api.RevisionedDao} using
 * {@link org.hibernate.envers Hibernate-Envers} to manage the revision-control.
 *
 * @param <ID> is the type of the {@link net.sf.mmm.util.entity.api.GenericEntity#getId() primary key} of the
 *        managed {@link net.sf.mmm.util.entity.api.GenericEntity}.
 * @param <ENTITY> is the {@link #getEntityClass() type} of the managed entity.
 *
 * @author Joerg Hohwiller (hohwille at users.sourceforge.net)
 */
public abstract class AbstractRevisionedDaoEnvers<ID, ENTITY extends MutableRevisionedEntity<ID>>
        extends AbstractJpaGenericDao<ID, ENTITY> implements RevisionedDao<ID, ENTITY> {

    /** @see #getPersistenceManager() */
    private PersistenceManager persistenceManager;

    /**
     * The constructor.
     */
    public AbstractRevisionedDaoEnvers() {

        super();
    }

    /**
     * @return the {@link PersistenceManager} instance.
     */
    protected PersistenceManager getPersistenceManager() {

        return this.persistenceManager;
    }

    /**
     * @param persistenceManager is the {@link PersistenceManager} to {@link Inject}.
     */
    @Inject
    public void setPersistenceManager(PersistenceManager persistenceManager) {

        getInitializationState().requireNotInitilized();
        this.persistenceManager = persistenceManager;
    }

    /**
     * @return the auditReader
     */
    protected AuditReader getAuditReader() {

        return AuditReaderFactory.get(getEntityManager());
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public ENTITY load(ID id, Number revision) throws ObjectNotFoundException {

        if (revision == RevisionedEntity.LATEST_REVISION) {
            return find(id);
        } else {
            return loadRevision(id, revision);
        }
    }

    /**
     * This method gets a historic revision of the {@link net.sf.mmm.util.entity.api.GenericEntity} with the
     * given <code>id</code>.
     *
     * @param id is the {@link net.sf.mmm.util.entity.api.GenericEntity#getId() ID} of the requested
     *        {@link net.sf.mmm.util.entity.api.GenericEntity entity}.
     * @param revision is the {@link RevisionedEntity#getRevision() revision}
     * @return the requested {@link net.sf.mmm.util.entity.api.GenericEntity entity}.
     * @throws ObjectNotFoundException if the requested {@link net.sf.mmm.util.entity.api.GenericEntity entity}
     *         could NOT be found.
     */
    protected ENTITY loadRevision(Object id, Number revision) throws ObjectNotFoundException {

        Class<? extends ENTITY> entityClassImplementation = getEntityClass();
        ENTITY entity = getAuditReader().find(entityClassImplementation, id, revision);
        if (entity != null) {
            entity.setRevision(revision);
        }
        return entity;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public Number createRevision(ENTITY entity) {

        // TODO:
        return null;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public List<Number> getRevisionHistory(ENTITY entity) {

        return getAuditReader().getRevisions(getEntityClass(), entity.getId());
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public List<RevisionMetadata> getRevisionHistoryMetadata(Object id) {

        AuditReader auditReader = getAuditReader();
        List<Number> revisionList = auditReader.getRevisions(getEntityClass(), id);
        List<RevisionMetadata> result = new ArrayList<RevisionMetadata>();
        for (Number revision : revisionList) {
            Long revisionLong = Long.valueOf(revision.longValue());
            result.add(new LazyRevisionMetadata(this.persistenceManager, revisionLong));
        }
        return result;
    }
}