runners/spark/src/main/java/org/apache/beam/runners/spark/structuredstreaming/translation/helpers/CoderHelpers.java

/*
 * 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.beam.runners.spark.structuredstreaming.translation.helpers;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import org.apache.beam.sdk.coders.Coder;

/** Serialization utility class. */
public final class CoderHelpers {
  private CoderHelpers() {}

  /**
   * Utility method for serializing an object using the specified coder.
   *
   * @param value Value to serialize.
   * @param coder Coder to serialize with.
   * @param <T> type of value that is serialized
   * @return Byte array representing serialized object.
   */
  public static <T> byte[] toByteArray(T value, Coder<T> coder) {
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    try {
      coder.encode(value, baos);
    } catch (IOException e) {
      throw new IllegalStateException("Error encoding value: " + value, e);
    }
    return baos.toByteArray();
  }

  /**
   * Utility method for deserializing a byte array using the specified coder.
   *
   * @param serialized bytearray to be deserialized.
   * @param coder Coder to deserialize with.
   * @param <T> Type of object to be returned.
   * @return Deserialized object.
   */
  public static <T> T fromByteArray(byte[] serialized, Coder<T> coder) {
    ByteArrayInputStream bais = new ByteArrayInputStream(serialized);
    try {
      return coder.decode(bais);
    } catch (IOException e) {
      throw new IllegalStateException("Error decoding bytes for coder: " + coder, e);
    }
  }
}