| /** |
| * 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 com.datatorrent.lib.util; |
| |
| import java.io.ByteArrayOutputStream; |
| import java.lang.reflect.Array; |
| |
| import org.apache.commons.io.IOUtils; |
| |
| import com.esotericsoftware.kryo.Kryo; |
| import com.esotericsoftware.kryo.io.Input; |
| import com.esotericsoftware.kryo.io.Output; |
| |
| /** |
| * |
| * A Kryo Clone Util class that clone object by using Kryo serializer and deserializer |
| * The class has static method that are can be used directly to clone one object |
| * Or it can be used as util instance to clone as many objects as you need from the one source object |
| * |
| * @since 3.4.0 |
| */ |
| public class KryoCloneUtils<T> |
| { |
| |
| /** |
| * Reusable Kryo object as deserializer |
| */ |
| private final Kryo kryo; |
| |
| /** |
| * Reusable binary data for object that would be deserialized from |
| */ |
| private final byte[] bin; |
| |
| /** |
| * The class of the object |
| */ |
| private final Class<T> clazz; |
| |
| @SuppressWarnings("unchecked") |
| private KryoCloneUtils(Kryo kryo, T t) |
| { |
| this.kryo = kryo; |
| ByteArrayOutputStream bos = null; |
| Output output = null; |
| try { |
| bos = new ByteArrayOutputStream(); |
| output = new Output(bos); |
| kryo.writeObject(output, t); |
| output.close(); |
| bin = bos.toByteArray(); |
| } finally { |
| IOUtils.closeQuietly(output); |
| IOUtils.closeQuietly(bos); |
| } |
| clazz = (Class<T>)t.getClass(); |
| kryo.setClassLoader(clazz.getClassLoader()); |
| } |
| |
| /** |
| * Clone from the binary data of the source object |
| * @return T |
| */ |
| public T getClone() |
| { |
| try (Input input = new Input(bin)) { |
| return kryo.readObject(input, clazz); |
| } |
| } |
| |
| /** |
| * Clone array of objects from source object |
| * @param num size of the return array |
| * @return array of T |
| */ |
| @SuppressWarnings("unchecked") |
| public T[] getClones(int num) |
| { |
| T[] ts = (T[])Array.newInstance(clazz, num); |
| try (Input input = new Input(bin)) { |
| for (int i = 0; i < ts.length; i++) { |
| input.rewind(); |
| ts[i] = kryo.readObject(input, clazz); |
| } |
| } |
| return ts; |
| } |
| |
| |
| |
| /** |
| * Clone object by serializing and deserializing using Kryo. |
| * Note this is different from using {@link Kryo#copy(Object)}, which will attempt to also clone transient fields. |
| * |
| * @param kryo kryo object used to clone objects |
| * @param src src object that copy from |
| * @return |
| */ |
| @SuppressWarnings("unchecked") |
| public static <SRC> SRC cloneObject(Kryo kryo, SRC src) |
| { |
| kryo.setClassLoader(src.getClass().getClassLoader()); |
| ByteArrayOutputStream bos = null; |
| Output output; |
| Input input = null; |
| try { |
| bos = new ByteArrayOutputStream(); |
| output = new Output(bos); |
| kryo.writeObject(output, src); |
| output.close(); |
| input = new Input(bos.toByteArray()); |
| return (SRC)kryo.readObject(input, src.getClass()); |
| } finally { |
| IOUtils.closeQuietly(input); |
| IOUtils.closeQuietly(bos); |
| } |
| } |
| |
| |
| /** |
| * Clone object by serializing and deserializing using default Kryo. |
| * Note this is different from using {@link Kryo#copy(Object)}, which will attempt to also clone transient fields. |
| * |
| * @param src src object that copy from |
| * @return |
| */ |
| public static <SRC> SRC cloneObject(SRC src) |
| { |
| return cloneObject(new Kryo(), src); |
| } |
| |
| /** |
| * Factory function to return CloneUtils object |
| * @param template |
| * @param <SRC> |
| * @return |
| */ |
| public static <SRC> KryoCloneUtils<SRC> createCloneUtils(SRC template) |
| { |
| return createCloneUtils(new Kryo(), template); |
| } |
| |
| /** |
| * Factory function to return CloneUtils object with customized Kryo |
| * @param kryo |
| * @param template |
| * @param <SRC> |
| * @return |
| */ |
| public static <SRC> KryoCloneUtils<SRC> createCloneUtils(Kryo kryo, SRC template) |
| { |
| return new KryoCloneUtils<>(kryo, template); |
| } |
| |
| } |