| /* |
| * 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.translation; |
| |
| import java.io.ByteArrayInputStream; |
| import java.io.ByteArrayOutputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.ObjectInputStream; |
| import java.io.ObjectOutputStream; |
| import java.io.OutputStream; |
| import java.io.Serializable; |
| import org.apache.beam.sdk.coders.Coder; |
| import org.apache.beam.sdk.util.VarInt; |
| import org.apache.beam.sdk.util.common.ElementByteSizeObserver; |
| import org.apache.beam.vendor.guava.v20_0.com.google.common.base.Throwables; |
| import org.apache.beam.vendor.guava.v20_0.com.google.common.io.ByteStreams; |
| |
| /** |
| * A holder object that lets you serialize an element with a Coder with minimal wasted space. |
| * Supports both Kryo and Java serialization. |
| * |
| * <p>There are two different representations: a deserialized representation and a serialized |
| * representation. |
| * |
| * <p>The deserialized representation stores a Coder and the value. To serialize the value, we write |
| * a length-prefixed encoding of value, but do NOT write the Coder used. |
| * |
| * <p>The serialized representation just reads a byte array - the value is not deserialized fully. |
| * In order to get at the deserialized value, the caller must pass the Coder used to create this |
| * instance via getOrDecode(Coder). This reverts the representation back to the deserialized |
| * representation. |
| * |
| * @param <T> element type |
| */ |
| public final class ValueAndCoderLazySerializable<T> implements Serializable { |
| private T value; |
| // Re-use a field to save space in-memory. This is either a byte[] or a Coder, depending on |
| // which representation we are in. |
| private Object coderOrBytes; |
| |
| private ValueAndCoderLazySerializable(T value, Coder<T> currentCoder) { |
| this.value = value; |
| this.coderOrBytes = currentCoder; |
| } |
| |
| @SuppressWarnings("unused") // for serialization |
| ValueAndCoderLazySerializable() {} |
| |
| public static <T> ValueAndCoderLazySerializable<T> of(T value, Coder<T> coder) { |
| return new ValueAndCoderLazySerializable<>(value, coder); |
| } |
| |
| public T getOrDecode(Coder<T> coder) { |
| if (!(coderOrBytes instanceof Coder)) { |
| ByteArrayInputStream bais = new ByteArrayInputStream((byte[]) this.coderOrBytes); |
| try { |
| value = coder.decode(bais); |
| } catch (IOException e) { |
| throw new IllegalStateException("Error decoding bytes for coder: " + coder, e); |
| } |
| this.coderOrBytes = coder; |
| } |
| |
| return value; |
| } |
| |
| private static class ByteSizeObserver extends ElementByteSizeObserver { |
| private long observedSize = 0; |
| |
| @Override |
| protected void reportElementSize(long elementByteSize) { |
| observedSize += elementByteSize; |
| } |
| } |
| |
| void writeCommon(OutputStream out) throws IOException { |
| if (!(coderOrBytes instanceof Coder)) { |
| byte[] bytes = (byte[]) coderOrBytes; |
| VarInt.encode(bytes.length, out); |
| out.write(bytes); |
| } else { |
| @SuppressWarnings("unchecked") |
| Coder<T> coder = (Coder<T>) coderOrBytes; |
| int bufferSize = 1024; |
| if (coder.isRegisterByteSizeObserverCheap(value)) { |
| try { |
| ByteSizeObserver observer = new ByteSizeObserver(); |
| coder.registerByteSizeObserver(value, observer); |
| bufferSize = (int) observer.observedSize; |
| } catch (Exception e) { |
| Throwables.throwIfUnchecked(e); |
| throw new RuntimeException(e); |
| } |
| } |
| |
| ByteArrayOutputStream bytes = new ByteArrayOutputStream(bufferSize); |
| try { |
| coder.encode(value, bytes); |
| VarInt.encode(bytes.size(), out); |
| bytes.writeTo(out); |
| } catch (IOException e) { |
| throw new RuntimeException(e); |
| } |
| } |
| } |
| |
| void readCommon(InputStream in) throws IOException { |
| int length = VarInt.decodeInt(in); |
| byte[] bytes = new byte[length]; |
| ByteStreams.readFully(in, bytes); |
| this.coderOrBytes = bytes; |
| } |
| |
| private void writeObject(ObjectOutputStream out) throws IOException { |
| writeCommon(out); |
| } |
| |
| private void readObject(ObjectInputStream in) throws IOException { |
| readCommon(in); |
| } |
| } |