org.messic.server.datamodel.jpaimpl.DAOJPA.java Source code

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Here is the source code for org.messic.server.datamodel.jpaimpl.DAOJPA.java

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/*
 * Copyright (C) 2013
 *
 *  This file is part of Messic.
 * 
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.messic.server.datamodel.jpaimpl;

import java.util.List;

import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;

import org.messic.server.datamodel.MDO;
import org.messic.server.datamodel.dao.DAO;
import org.springframework.transaction.annotation.Transactional;

@Transactional
public class DAOJPA<T extends MDO> implements DAO<T> {
    private Class<T> type;

    protected EntityManager entityManager;

    @PersistenceContext
    public void setEntityManager(EntityManager entityManager) {
        this.entityManager = entityManager;
    }

    public DAOJPA(Class<T> type) {
        super();
        this.type = type;
    }

    @Transactional
    public T get(Long id) {
        if (id == null) {
            return null;
        } else {
            return entityManager.find(type, id);
        }
    }

    @Transactional
    public T merge(T c) {
        return entityManager.merge(c);
    }

    @SuppressWarnings("unchecked")
    @Transactional
    public List<T> getAll() {
        return entityManager.createQuery("from " + type.getName()).getResultList();
    }

    @Transactional(readOnly = true)
    public long getCount() {
        Query q = entityManager.createQuery("SELECT COUNT(e) FROM " + type.getName() + " e");
        return (Long) q.getSingleResult();
    }

    @Transactional
    public void save(T object) {
        entityManager.persist(object);
    }

    @Transactional
    public void remove(T object) {
        entityManager.remove(object);
    }
}