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.Serializer;
  import org.apache.kafka.streams.kstream.internals.WrappingNullableSerializer;
  import org.apache.kafka.streams.processor.internals.SerdeGetter;
  
  import java.nio.ByteBuffer;
  import java.util.Map;
  
  import static org.apache.kafka.streams.kstream.internals.WrappingNullableUtils.initNullableSerializer;
  
  /**
   * Serializes a {@link LeftOrRightValue}. The serialized bytes starts with a byte that references
   * to whether the value is V1 or V2.
   */
  public class LeftOrRightValueSerializer<V1, V2> implements WrappingNullableSerializer<LeftOrRightValue<V1, V2>, Void, Object> {
      private Serializer<V1> leftSerializer;
      private Serializer<V2> rightSerializer;
  
      public LeftOrRightValueSerializer(final Serializer<V1> leftSerializer, final Serializer<V2> rightSerializer) {
          this.leftSerializer = leftSerializer;
          this.rightSerializer = rightSerializer;
      }
  
      @SuppressWarnings("unchecked")
      @Override
      public void setIfUnset(final SerdeGetter getter) {
          if (leftSerializer == null) {
              leftSerializer = (Serializer<V1>) getter.valueSerde().serializer();
          }
  
          if (rightSerializer == null) {
              rightSerializer = (Serializer<V2>) getter.valueSerde().serializer();
          }
  
          initNullableSerializer(leftSerializer, getter);
          initNullableSerializer(rightSerializer, getter);
      }
  
      @Override
      public void configure(final Map<String, ?> configs, final boolean isKey) {
          leftSerializer.configure(configs, isKey);
          rightSerializer.configure(configs, isKey);
      }
  
      @Override
      public byte[] serialize(final String topic, final LeftOrRightValue<V1, V2> data) {
          if (data == null) {
              return null;
          }
  
          final byte[] rawValue = (data.leftValue() != null)
              ? leftSerializer.serialize(topic, data.leftValue())
              : rightSerializer.serialize(topic, data.rightValue());
  
          if (rawValue == null) {
              return null;
          }
  
          return ByteBuffer
              .allocate(1 + rawValue.length)
              .put((byte) (data.leftValue() != null ? 1 : 0))
              .put(rawValue)
              .array();
      }
  
      @Override
      public void close() {
          leftSerializer.close();
          rightSerializer.close();
      }
  }
  