content: /*
   * 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.kafka.streams.processor.api;
  
  import org.apache.kafka.streams.kstream.ValueTransformerWithKeySupplier;
  import org.apache.kafka.streams.processor.Punctuator;
  
  public interface RecordMetadata {
      /**
       * Return the topic name of the current input record; could be {@code null} if it is not
       * available.
       *
       * <p> For example, if this method is invoked within a {@link Punctuator#punctuate(long)
       * punctuation callback}, or while processing a record that was forwarded by a punctuation
       * callback, the record won't have an associated topic.
       * Another example is
       * {@link org.apache.kafka.streams.kstream.KTable#transformValues(ValueTransformerWithKeySupplier, String...)}
       * (and siblings), that do not always guarantee to provide a valid topic name, as they might be
       * executed "out-of-band" due to some internal optimizations applied by the Kafka Streams DSL.
       *
       * @return the topic name
       */
      String topic();
  
      /**
       * Return the partition id of the current input record; could be {@code -1} if it is not
       * available.
       *
       * <p> For example, if this method is invoked within a {@link Punctuator#punctuate(long)
       * punctuation callback}, or while processing a record that was forwarded by a punctuation
       * callback, the record won't have an associated partition id.
       * Another example is
       * {@link org.apache.kafka.streams.kstream.KTable#transformValues(ValueTransformerWithKeySupplier, String...)}
       * (and siblings), that do not always guarantee to provide a valid partition id, as they might be
       * executed "out-of-band" due to some internal optimizations applied by the Kafka Streams DSL.
       *
       * @return the partition id
       */
      int partition();
  
      /**
       * Return the offset of the current input record; could be {@code -1} if it is not
       * available.
       *
       * <p> For example, if this method is invoked within a {@link Punctuator#punctuate(long)
       * punctuation callback}, or while processing a record that was forwarded by a punctuation
       * callback, the record won't have an associated offset.
       * Another example is
       * {@link org.apache.kafka.streams.kstream.KTable#transformValues(ValueTransformerWithKeySupplier, String...)}
       * (and siblings), that do not always guarantee to provide a valid offset, as they might be
       * executed "out-of-band" due to some internal optimizations applied by the Kafka Streams DSL.
       *
       * @return the offset
       */
      long offset();
  }
  