GenericDAO.java

//
// Copyright 2009 Robin Komiwes, Bruno Verachten, Christophe Cordenier
//
// 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.wooki.domain.dao;

import java.io.Serializable;
import java.util.List;

import org.hibernate.Criteria;

import com.wooki.services.db.QueryFilter;

/**
 * Generic DAO will be the base for all concrete DAO implementation. It will provide generic data
 * access method.
 * 
 * @param <T>
 * @param <PK>
 */
public interface GenericDAO<T, PK extends Serializable>
{
    /**
     * Retrieve an object that was previously persisted to the database using the indicated id as
     * primary key
     */
    T findById(PK id);

    /**
     * Persist the newInstance object into database
     */

    T create(T newInstance);

    /**
     * Save changes made to a persistent object.
     * 
     * @return Updated object
     */
    T update(T transientObject);

    /**
     * Remove an object from persistent storage in the database
     */
    void delete(T persistentObject);

    /**
     * Refresh the object to its db values. 
     *
     * @param persistentObject
     */
    void refresh(T persistentObject);
    
    /**
     * Create a new <tt>Criteria</tt> instance, for the current entity class, or a superclass of an
     * entity class.
     * 
     * @return Criteria
     */
    public Criteria createCriteria();

    /**
     * Create a simple criteria based on a column name and a value.
     * 
     * @param col
     * @param value
     * @return
     */
    public Criteria createColumnCriteria(String col, Object value);

    /**
     * Create a new <tt>Criteria</tt> instance, for the current entity class, or a superclass of an
     * entity class, with the given alias.
     * 
     * @param String
     *            alias
     * @return Criteria
     */
    public Criteria createCriteria(String alias);

    /**
     * List all the persistent entities of type T
     */
    List<T> list(QueryFilter... filters);
}