distributedlog-tutorials/distributedlog-messaging/src/main/java/com/twitter/distributedlog/messaging/Transformer.java

/**
 * 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 com.twitter.distributedlog.messaging;

/**
 * Transform one format to the other format.
 */
public interface Transformer<T, R> {

    /**
     * Transform value <i>T</i> to value <i>R</i>. If null is returned,
     * the value <i>T</i> will be eliminated without transforming.
     *
     * @param value value to transform
     * @return transformed value
     */
    R transform(T value);

}