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;
  
  import org.apache.kafka.common.header.Headers;
  import org.apache.kafka.streams.kstream.ValueTransformerWithKeySupplier;
  
  /**
   * The context associated with the current record being processed by
   * a {@link org.apache.kafka.streams.processor.api.Processor}
   */
  public interface RecordContext {
  
      /**
       * 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();
  
      /**
       * Return the current timestamp.
       *
       * <p> If it is triggered while processing a record streamed from the source processor,
       * timestamp is defined as the timestamp of the current input record; the timestamp is extracted from
       * {@link org.apache.kafka.clients.consumer.ConsumerRecord ConsumerRecord} by {@link TimestampExtractor}.
       * Note, that an upstream {@link org.apache.kafka.streams.processor.api.Processor}
       * might have set a new timestamp by calling
       * {@link org.apache.kafka.streams.processor.api.ProcessorContext#forward(org.apache.kafka.streams.processor.api.Record)
       * forward(..., To.all().withTimestamp(...))}.
       * In particular, some Kafka Streams DSL operators set result record timestamps explicitly,
       * to guarantee deterministic results.
       *
       * <p> If it is triggered while processing a record generated not from the source processor (for example,
       * if this method is invoked from the punctuate call), timestamp is defined as the current
       * task's stream time, which is defined as the largest timestamp of any record processed by the task.
       *
       * @return the timestamp
       */
      long timestamp();
  
      /**
       * Return the headers of the current input record; could be an empty header 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 might not have any associated headers.
       * Another example is
       * {@link org.apache.kafka.streams.kstream.KTable#transformValues(ValueTransformerWithKeySupplier, String...)}
       * (and siblings), that do not always guarantee to provide a valid headers, as they might be
       * executed "out-of-band" due to some internal optimizations applied by the Kafka Streams DSL.
       *
       * @return the headers
       */
      Headers headers();
  
      /**
       * Return the non-deserialized byte[] of the input message key if the context has been triggered by a message.
       *
       * <p> 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, it will return {@code null}.
       *
       * <p> If this method is invoked in a sub-topology due to a repartition, the returned key would be one sent
       * to the repartition topic.
       *
       * @return the raw byte of the key of the source message
       */
      byte[] sourceRawKey();
  
      /**
       * Return the non-deserialized byte[] of the input message value if the context has been triggered by a message.
       *
       * <p> 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, it will return {@code null}.
       *
       * <p> If this method is invoked in a sub-topology due to a repartition, the returned key would be one sent
       * to the repartition topic.
       *
       * @return the raw byte of the value of the source message
       */
      byte[] sourceRawValue();
  }
  