| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.axis2.clustering.configuration; |
| |
| import org.apache.axis2.clustering.ClusteringCommand; |
| import org.apache.axis2.context.ConfigurationContext; |
| |
| /** |
| * This class represents the 2-phase commit protocol, where an event is processed, |
| * the system is prepared to switch to a new configuration based on the processed event, |
| * and finally commits the new configuration (i.e. the system switches to the new configuration). |
| * As can be seen, this is a 3-step process. |
| */ |
| public abstract class ConfigurationClusteringCommand extends ClusteringCommand { |
| |
| public static final int RELOAD_CONFIGURATION = 0; |
| public static final int LOAD_SERVICE_GROUPS = 1; |
| public static final int UNLOAD_SERVICE_GROUPS = 2; |
| public static final int APPLY_SERVICE_POLICY = 3; |
| public static final int PREPARE = 4; |
| public static final int COMMIT = 5; |
| public static final int EXCEPTION = 6; |
| public static final int ROLLBACK = 7; |
| |
| /** |
| * Get the command type |
| * |
| * @return The command type |
| */ |
| public abstract int getCommandType(); |
| |
| /** |
| * Process the <code>event</event>. The implementer of this interface will |
| * need to cache the outcome of this processing. |
| * |
| * @param configContext |
| * @throws Exception |
| */ |
| public abstract void process(ConfigurationContext configContext) throws Exception; |
| |
| /** |
| * Prepare to switch to the new configuration |
| * |
| * @param configContext |
| */ |
| public abstract void prepare(ConfigurationContext configContext); |
| |
| /** |
| * Commit the new configuration. i.e. switch the system to the new configuration |
| * |
| * @param configContext |
| * @throws Exception |
| */ |
| public abstract void commit(ConfigurationContext configContext) throws Exception; |
| |
| /** |
| * Rollback any changes carried out |
| * |
| * @param configContext |
| * @throws Exception |
| */ |
| public abstract void rollback(ConfigurationContext configContext) throws Exception; |
| } |