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 backtype.storm.state;
  
  import com.esotericsoftware.kryo.Kryo;
  import com.esotericsoftware.kryo.io.Input;
  import com.esotericsoftware.kryo.io.Output;
  
  import java.util.Collections;
  import java.util.List;
  
  /**
   * A default implementation that uses Kryo to serialize and de-serialize the state.
   */
  public class DefaultStateSerializer<T> implements Serializer<T> {
      private final Kryo kryo;
      private final Output output;
  
      /**
       * Constructs a {@link DefaultStateSerializer} instance with the given list
       * of classes registered in kryo.
       *
       * @param classesToRegister the classes to register.
       */
      public DefaultStateSerializer(List<Class<?>> classesToRegister) {
          kryo = new Kryo();
          output = new Output(2000, 2000000000);
          for (Class<?> klazz : classesToRegister) {
              kryo.register(klazz);
          }
      }
  
      public DefaultStateSerializer() {
          this(Collections.<Class<?>>emptyList());
      }
  
      @Override
      public byte[] serialize(T obj) {
          output.clear();
          kryo.writeClassAndObject(output, obj);
          return output.toBytes();
      }
  
      @Override
      public T deserialize(byte[] b) {
          Input input = new Input(b);
          return (T) kryo.readClassAndObject(input);
      }
  }
  