/*
 * Copyright 2005-2010 the original author or authors.
 * 
 * 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 org.wamblee.persistence;

import java.io.Serializable;

/**
 * Interface for persistent objects. This defines a generic interface for
 * accessing primary key and version of entities.
 */
public interface Persistent {
    /**
     * Gets the primary key.
     * 
     * @return Primary key.
     * 
     * @see #setPrimaryKey(Serializable)
     */
    Serializable getPrimaryKey();

    /**
     * Sets the primary key.
     * 
     * @param aKey
     *            Primary key.
     * 
     * @see #getPrimaryKey()
     */
    void setPrimaryKey(Serializable aKey);

    /**
     * Gets the version.
     * 
     * @return Version.
     * 
     * @see #setPersistedVersion(int)
     */
    Number getPersistedVersion();

    /**
     * Sets the version.
     * 
     * @param aVersion
     *            Version.
     * 
     * @see #getPersistedVersion()
     */
    void setPersistedVersion(Number aVersion);
}