/*
 * Copyright 2005-2011 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.xmlrouter.impl;

/**
 * The XML Router configuration contains both configuration data as well as
 * derived data used by the XML router. It is important that all this data is
 * consistent. Therefore, this class provides a read-write locking mechanism for
 * accessing the data.
 * 
 * @author Erik Brakkee
 * 
 */
public interface XMLRouterConfiguration {

    /**
     * To be called before the configuration is used. Corresponds to read lock
     * acquire.
     */
    void startPublishEvent();

    /**
     * @return Configuration data. {@link #startPublishEvent()} must have been
     *         called before doing this.
     */
    ExtendedRouterConfig getRouterConfig();

    /**
     * @return Transformation paths (derived data).
     */
    TransformationPaths getTransformations();

    /**
     * To be called after the configuration is used. Corresponds to read lock
     * release.
     */
    void endPublishEvent();

    /**
     * Atomically sets the configuration and updates derived data. There will be
     * a short time during which read attempts will fail.
     * 
     * @param aConfig
     *            Configuration to set.
     */
    void setRouterConfig(ExtendedRouterConfig aConfig);
}