/*
 * Copyright (c) 2002-2012 Alibaba Group Holding Limited.
 * All rights reserved.
 *
 * 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.alibaba.citrus.service.requestcontext.session;

/**
 * 将session model转换为store中可存储的对象，或者将store中取得的对象转换回session model。
 *
 * @author Michael Zhou
 */
public interface SessionModelEncoder {
    /** 将session model转换成store中可存储的对象。 */
    Object encode(SessionModel model);

    /**
     * 将store中取得的数据转换成session model。
     * <p>
     * 如果返回<code>null</code>，则数据格式不支持。框架将会尝试用其余的<code>SessionModelEncoder</code>
     * 来解码。
     * </p>
     */
    SessionModel decode(Object data, SessionModel.Factory factory);
}