org.apache.camel.resume.ResumeStrategy Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of camel-api Show documentation
The Camel API
The newest version!
/*
 * 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.camel.resume;

import org.apache.camel.Service;

/**
 * Defines a strategy for handling resume operations. Implementations can define different ways to handle how to resume
 * processing records.
 */
public interface ResumeStrategy extends Service {
    /**
     * A callback that can be executed after the last offset is updated
     */
    @FunctionalInterface
    interface UpdateCallBack {
        /**
         * The method to execute after the last offset is updated
         *
         * @param throwable an instance of a Throwable if an exception was thrown during the update process
         */
        void onUpdate(Throwable throwable);
    }

    String DEFAULT_NAME = "resumeStrategy";

    /**
     * Sets an adapter for resuming operations with this strategy
     *
     * @param adapter the component-specific resume adapter
     */
    void setAdapter(ResumeAdapter adapter);

    /**
     * Gets an adapter for resuming operations
     */
    ResumeAdapter getAdapter();

    /**
     * Gets and adapter for resuming operations
     *
     * @param  clazz the class of the adapter
     * @return       the adapter or null if it can't be cast to the requested class
     * @param     the type of the adapter
     */
    default  T getAdapter(Class clazz) {
        return clazz.cast(getAdapter());
    }

    /**
     * Loads the cache with the data currently available in this strategy
     *
     * @throws Exception
     */
    default void loadCache() throws Exception {

    }

    /**
     * Updates the last processed offset
     *
     * @param  offset    the offset to update
     * @throws Exception if unable to update the offset
     */
     void updateLastOffset(T offset) throws Exception;

    /**
     * Updates the last processed offset
     *
     * @param  offset         the offset to update
     * @param  updateCallBack a callback to be executed after the updated has occurred (null if not available)
     * @throws Exception      if unable to update the offset
     */
     void updateLastOffset(T offset, UpdateCallBack updateCallBack) throws Exception;

    /**
     * Updates the last processed offset
     *
     * @param  offsetKey   the offset key to update
     * @param  offsetValue the offset value to update
     * @throws Exception   if unable to update the offset
     */
    void updateLastOffset(OffsetKey offsetKey, Offset offsetValue) throws Exception;

    /**
     * Updates the last processed offset
     *
     * @param  offsetKey      the offset key to update
     * @param  offset         the offset value to update
     * @param  updateCallBack a callback to be executed after the updated has occurred (null if not available)
     * @throws Exception      if unable to update the offset
     */
    void updateLastOffset(OffsetKey offsetKey, Offset offset, UpdateCallBack updateCallBack) throws Exception;

    void setResumeStrategyConfiguration(ResumeStrategyConfiguration resumeStrategyConfiguration);

    ResumeStrategyConfiguration getResumeStrategyConfiguration();
}