| /* |
| * 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.sdk.coders; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import org.apache.beam.sdk.util.ExposedByteArrayOutputStream; |
| import org.apache.beam.sdk.util.StreamUtils; |
| import org.apache.beam.sdk.util.VarInt; |
| import org.apache.beam.sdk.values.TypeDescriptor; |
| import org.apache.beam.vendor.guava.v20_0.com.google.common.io.ByteStreams; |
| |
| /** |
| * A {@link Coder} for {@code byte[]}. |
| * |
| * <p>The encoding format is as follows: |
| * |
| * <ul> |
| * <li>If in a non-nested context (the {@code byte[]} is the only value in the stream), the bytes |
| * are read/written directly. |
| * <li>If in a nested context, the bytes are prefixed with the length of the array, encoded via a |
| * {@link VarIntCoder}. |
| * </ul> |
| */ |
| public class ByteArrayCoder extends AtomicCoder<byte[]> { |
| |
| public static ByteArrayCoder of() { |
| return INSTANCE; |
| } |
| |
| ///////////////////////////////////////////////////////////////////////////// |
| |
| private static final ByteArrayCoder INSTANCE = new ByteArrayCoder(); |
| private static final TypeDescriptor<byte[]> TYPE_DESCRIPTOR = new TypeDescriptor<byte[]>() {}; |
| |
| private ByteArrayCoder() {} |
| |
| @Override |
| public void encode(byte[] value, OutputStream outStream) throws IOException, CoderException { |
| encode(value, outStream, Context.NESTED); |
| } |
| |
| @Override |
| public void encode(byte[] value, OutputStream outStream, Context context) |
| throws IOException, CoderException { |
| if (value == null) { |
| throw new CoderException("cannot encode a null byte[]"); |
| } |
| if (!context.isWholeStream) { |
| VarInt.encode(value.length, outStream); |
| outStream.write(value); |
| } else { |
| outStream.write(value); |
| } |
| } |
| |
| /** |
| * Encodes the provided {@code value} with the identical encoding to {@link #encode}, but with |
| * optimizations that take ownership of the value. |
| * |
| * <p>Once passed to this method, {@code value} should never be observed or mutated again. |
| */ |
| public void encodeAndOwn(byte[] value, OutputStream outStream, Context context) |
| throws IOException, CoderException { |
| if (!context.isWholeStream) { |
| VarInt.encode(value.length, outStream); |
| outStream.write(value); |
| } else { |
| if (outStream instanceof ExposedByteArrayOutputStream) { |
| ((ExposedByteArrayOutputStream) outStream).writeAndOwn(value); |
| } else { |
| outStream.write(value); |
| } |
| } |
| } |
| |
| @Override |
| public byte[] decode(InputStream inStream) throws IOException, CoderException { |
| return decode(inStream, Context.NESTED); |
| } |
| |
| @Override |
| public byte[] decode(InputStream inStream, Context context) throws IOException, CoderException { |
| if (context.isWholeStream) { |
| return StreamUtils.getBytesWithoutClosing(inStream); |
| } else { |
| int length = VarInt.decodeInt(inStream); |
| if (length < 0) { |
| throw new IOException("invalid length " + length); |
| } |
| byte[] value = new byte[length]; |
| ByteStreams.readFully(inStream, value); |
| return value; |
| } |
| } |
| |
| @Override |
| public void verifyDeterministic() {} |
| |
| /** |
| * {@inheritDoc} |
| * |
| * @return objects that are equal if the two arrays contain the same bytes. |
| */ |
| @Override |
| public Object structuralValue(byte[] value) { |
| return new StructuralByteArray(value); |
| } |
| |
| /** |
| * {@inheritDoc} |
| * |
| * @return {@code true} since {@link #getEncodedElementByteSize} runs in constant time using the |
| * {@code length} of the provided array. |
| */ |
| @Override |
| public boolean isRegisterByteSizeObserverCheap(byte[] value) { |
| return true; |
| } |
| |
| @Override |
| public TypeDescriptor<byte[]> getEncodedTypeDescriptor() { |
| return TYPE_DESCRIPTOR; |
| } |
| |
| @Override |
| protected long getEncodedElementByteSize(byte[] value) throws Exception { |
| if (value == null) { |
| throw new CoderException("cannot encode a null byte[]"); |
| } |
| return (long) VarInt.getLength(value.length) + value.length; |
| } |
| } |