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.state.internals;
  
  import org.apache.kafka.common.serialization.Deserializer;
  import org.apache.kafka.common.serialization.LongDeserializer;
  import org.apache.kafka.streams.kstream.internals.WrappingNullableDeserializer;
  import org.apache.kafka.streams.processor.internals.SerdeGetter;
  import org.apache.kafka.streams.state.StateSerdes;
  
  import java.util.Map;
  
  import static org.apache.kafka.streams.kstream.internals.WrappingNullableUtils.initNullableDeserializer;
  
  /**
   * The deserializer that is used for {@link TimestampedKeyAndJoinSide}, which is a combo key format of <timestamp, left/right flag, raw-key>
   * @param <K> the raw key type
   */
  public class TimestampedKeyAndJoinSideDeserializer<K> implements WrappingNullableDeserializer<TimestampedKeyAndJoinSide<K>, K, Void> {
      private Deserializer<K> keyDeserializer;
      private final Deserializer<Long> timestampDeserializer = new LongDeserializer();
  
      TimestampedKeyAndJoinSideDeserializer(final Deserializer<K> keyDeserializer) {
          this.keyDeserializer = keyDeserializer;
      }
  
      @SuppressWarnings("unchecked")
      @Override
      public void setIfUnset(final SerdeGetter getter) {
          if (keyDeserializer == null) {
              keyDeserializer = (Deserializer<K>) getter.keySerde().deserializer();
          }
  
          initNullableDeserializer(keyDeserializer, getter);
      }
  
      @Override
      public void configure(final Map<String, ?> configs, final boolean isKey) {
          keyDeserializer.configure(configs, isKey);
      }
  
      @Override
      public TimestampedKeyAndJoinSide<K> deserialize(final String topic, final byte[] data) {
          final boolean isLeft = data[StateSerdes.TIMESTAMP_SIZE] == 1;
          final K key = keyDeserializer.deserialize(topic, rawKey(data));
          final long timestamp = timestampDeserializer.deserialize(topic, rawTimestamp(data));
  
          return isLeft ? TimestampedKeyAndJoinSide.makeLeft(key, timestamp) :
                  TimestampedKeyAndJoinSide.makeRight(key, timestamp);
      }
  
      private byte[] rawTimestamp(final byte[] data) {
          final byte[] rawTimestamp = new byte[8];
          System.arraycopy(data, 0, rawTimestamp, 0, 8);
          return rawTimestamp;
      }
  
      private byte[] rawKey(final byte[] data) {
          final byte[] rawKey = new byte[data.length - StateSerdes.TIMESTAMP_SIZE - StateSerdes.BOOLEAN_SIZE];
          System.arraycopy(data, StateSerdes.TIMESTAMP_SIZE + StateSerdes.BOOLEAN_SIZE, rawKey, 0, rawKey.length);
          return rawKey;
      }
  
      @Override
      public void close() {
          keyDeserializer.close();
      }
  }
  