2 * Copyright 2014-present Open Networking Foundation
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
16 package io.atomix.utils.serializer;
18 import com.esotericsoftware.kryo.Kryo;
19 import com.esotericsoftware.kryo.Registration;
20 import com.esotericsoftware.kryo.Serializer;
21 import com.esotericsoftware.kryo.io.ByteBufferInput;
22 import com.esotericsoftware.kryo.io.ByteBufferOutput;
23 import com.esotericsoftware.kryo.pool.KryoCallback;
24 import com.esotericsoftware.kryo.pool.KryoFactory;
25 import com.esotericsoftware.kryo.pool.KryoPool;
26 import com.google.common.base.MoreObjects;
27 import com.google.common.collect.ImmutableList;
28 import org.objenesis.strategy.StdInstantiatorStrategy;
29 import org.slf4j.Logger;
30 import org.slf4j.LoggerFactory;
32 import java.io.ByteArrayInputStream;
33 import java.io.InputStream;
34 import java.io.OutputStream;
35 import java.nio.ByteBuffer;
36 import java.util.ArrayList;
37 import java.util.Arrays;
38 import java.util.List;
40 import java.util.Map.Entry;
41 import java.util.Objects;
43 import static java.util.Objects.requireNonNull;
46 * Pool of Kryo instances, with classes pre-registered.
49 public final class Namespace implements KryoFactory, KryoPool {
52 * Default buffer size used for serialization.
54 * @see #serialize(Object)
56 public static final int DEFAULT_BUFFER_SIZE = 4096;
59 * ID to use if this KryoNamespace does not define registration id.
61 private static final int FLOATING_ID = -1;
64 * Smallest ID free to use for user defined registrations.
66 private static final int INITIAL_ID = 16;
68 static final String NO_NAME = "(no name)";
70 private static final Logger LOGGER = LoggerFactory.getLogger(Namespace.class);
72 private final KryoPool kryoPool = new KryoPool.Builder(this).softReferences().build();
74 private final KryoOutputPool kryoOutputPool = new KryoOutputPool();
75 private final KryoInputPool kryoInputPool = new KryoInputPool();
77 private final ImmutableList<RegistrationBlock> registeredBlocks;
79 private final ClassLoader classLoader;
80 private final String friendlyName;
83 * KryoNamespace builder.
86 public static final class Builder {
87 private int blockHeadId = INITIAL_ID;
88 private List<Entry<Class<?>[], Serializer<?>>> types = new ArrayList<>();
89 private List<RegistrationBlock> blocks = new ArrayList<>();
90 private ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
93 * Builds a {@link Namespace} instance.
95 * @return KryoNamespace
97 public Namespace build() {
98 return build(NO_NAME);
102 * Builds a {@link Namespace} instance.
104 * @param friendlyName friendly name for the namespace
105 * @return KryoNamespace
107 public Namespace build(String friendlyName) {
108 if (!types.isEmpty()) {
109 blocks.add(new RegistrationBlock(this.blockHeadId, types));
111 return new Namespace(blocks, classLoader, friendlyName).populate(1);
115 * Registers serializer for the given set of classes.
117 * When multiple classes are registered with an explicitly provided serializer, the namespace guarantees
118 * all instances will be serialized with the same type ID.
120 * @param classes list of classes to register
121 * @param serializer serializer to use for the class
124 public Builder register(Serializer<?> serializer, final Class<?>... classes) {
125 types.add(Map.entry(classes, serializer));
130 * Sets the namespace class loader.
132 * @param classLoader the namespace class loader
133 * @return the namespace builder
135 public Builder setClassLoader(ClassLoader classLoader) {
136 this.classLoader = classLoader;
142 * Creates a new {@link Namespace} builder.
146 public static Builder builder() {
147 return new Builder();
151 * Creates a Kryo instance pool.
153 * @param registeredTypes types to register
154 * @param registrationRequired whether registration is required
155 * @param friendlyName friendly name for the namespace
158 final List<RegistrationBlock> registeredTypes,
159 ClassLoader classLoader,
160 String friendlyName) {
161 this.registeredBlocks = ImmutableList.copyOf(registeredTypes);
162 this.classLoader = classLoader;
163 this.friendlyName = requireNonNull(friendlyName);
167 * Populates the Kryo pool.
169 * @param instances to add to the pool
172 public Namespace populate(int instances) {
174 for (int i = 0; i < instances; ++i) {
181 * Serializes given object to byte array using Kryo instance in pool.
183 * Note: Serialized bytes must be smaller than {@link #MAX_BUFFER_SIZE}.
185 * @param obj Object to serialize
186 * @return serialized bytes
188 public byte[] serialize(final Object obj) {
189 return serialize(obj, DEFAULT_BUFFER_SIZE);
193 * Serializes given object to byte array using Kryo instance in pool.
195 * @param obj Object to serialize
196 * @param bufferSize maximum size of serialized bytes
197 * @return serialized bytes
199 public byte[] serialize(final Object obj, final int bufferSize) {
200 return kryoOutputPool.run(output -> {
201 return kryoPool.run(kryo -> {
202 kryo.writeClassAndObject(output, obj);
204 return output.getByteArrayOutputStream().toByteArray();
210 * Serializes given object to byte buffer using Kryo instance in pool.
212 * @param obj Object to serialize
213 * @param buffer to write to
215 public void serialize(final Object obj, final ByteBuffer buffer) {
216 ByteBufferOutput out = new ByteBufferOutput(buffer);
217 Kryo kryo = borrow();
219 kryo.writeClassAndObject(out, obj);
227 * Serializes given object to OutputStream using Kryo instance in pool.
229 * @param obj Object to serialize
230 * @param stream to write to
232 public void serialize(final Object obj, final OutputStream stream) {
233 serialize(obj, stream, DEFAULT_BUFFER_SIZE);
237 * Serializes given object to OutputStream using Kryo instance in pool.
239 * @param obj Object to serialize
240 * @param stream to write to
241 * @param bufferSize size of the buffer in front of the stream
243 public void serialize(final Object obj, final OutputStream stream, final int bufferSize) {
244 ByteBufferOutput out = new ByteBufferOutput(stream, bufferSize);
245 Kryo kryo = borrow();
247 kryo.writeClassAndObject(out, obj);
255 * Deserializes given byte array to Object using Kryo instance in pool.
257 * @param bytes serialized bytes
258 * @param <T> deserialized Object type
259 * @return deserialized Object
261 public <T> T deserialize(final byte[] bytes) {
262 return kryoInputPool.run(input -> {
263 input.setInputStream(new ByteArrayInputStream(bytes));
264 return kryoPool.run(kryo -> {
265 @SuppressWarnings("unchecked")
266 T obj = (T) kryo.readClassAndObject(input);
269 }, DEFAULT_BUFFER_SIZE);
273 * Deserializes given byte buffer to Object using Kryo instance in pool.
275 * @param buffer input with serialized bytes
276 * @param <T> deserialized Object type
277 * @return deserialized Object
279 public <T> T deserialize(final ByteBuffer buffer) {
280 ByteBufferInput in = new ByteBufferInput(buffer);
281 Kryo kryo = borrow();
283 @SuppressWarnings("unchecked")
284 T obj = (T) kryo.readClassAndObject(in);
292 * Deserializes given InputStream to an Object using Kryo instance in pool.
294 * @param stream input stream
295 * @param <T> deserialized Object type
296 * @return deserialized Object
298 public <T> T deserialize(final InputStream stream) {
299 return deserialize(stream, DEFAULT_BUFFER_SIZE);
303 * Deserializes given InputStream to an Object using Kryo instance in pool.
305 * @param stream input stream
306 * @param <T> deserialized Object type
307 * @param bufferSize size of the buffer in front of the stream
308 * @return deserialized Object
310 public <T> T deserialize(final InputStream stream, final int bufferSize) {
311 ByteBufferInput in = new ByteBufferInput(stream, bufferSize);
312 Kryo kryo = borrow();
314 @SuppressWarnings("unchecked")
315 T obj = (T) kryo.readClassAndObject(in);
323 * Creates a Kryo instance.
325 * @return Kryo instance
328 public Kryo create() {
329 LOGGER.trace("Creating Kryo instance for {}", this);
330 Kryo kryo = new Kryo();
331 kryo.setClassLoader(classLoader);
332 kryo.setRegistrationRequired(true);
334 // TODO rethink whether we want to use StdInstantiatorStrategy
335 kryo.setInstantiatorStrategy(
336 new Kryo.DefaultInstantiatorStrategy(new StdInstantiatorStrategy()));
338 for (RegistrationBlock block : registeredBlocks) {
339 int id = block.begin();
340 if (id == FLOATING_ID) {
341 id = kryo.getNextRegistrationId();
343 for (Entry<Class<?>[], Serializer<?>> entry : block.types()) {
344 register(kryo, entry.getKey(), entry.getValue(), id++);
351 * Register {@code type} and {@code serializer} to {@code kryo} instance.
353 * @param kryo Kryo instance
354 * @param types types to register
355 * @param serializer Specific serializer to register or null to use default.
356 * @param id type registration id to use
358 private void register(Kryo kryo, Class<?>[] types, Serializer<?> serializer, int id) {
359 Registration existing = kryo.getRegistration(id);
360 if (existing != null) {
361 boolean matches = false;
362 for (Class<?> type : types) {
363 if (existing.getType() == type) {
370 LOGGER.error("{}: Failed to register {} as {}, {} was already registered.",
371 friendlyName, types, id, existing.getType());
373 throw new IllegalStateException(String.format(
374 "Failed to register %s as %s, %s was already registered.",
375 Arrays.toString(types), id, existing.getType()));
377 // falling through to register call for now.
378 // Consider skipping, if there's reasonable
379 // way to compare serializer equivalence.
382 for (Class<?> type : types) {
383 Registration r = null;
384 if (serializer == null) {
385 r = kryo.register(type, id);
386 } else if (type.isInterface()) {
387 kryo.addDefaultSerializer(type, serializer);
389 r = kryo.register(type, serializer, id);
392 if (r.getId() != id) {
393 LOGGER.debug("{}: {} already registered as {}. Skipping {}.",
394 friendlyName, r.getType(), r.getId(), id);
396 LOGGER.trace("{} registered as {}", r.getType(), r.getId());
402 public Kryo borrow() {
403 return kryoPool.borrow();
407 public void release(Kryo kryo) {
408 kryoPool.release(kryo);
412 public <T> T run(KryoCallback<T> callback) {
413 return kryoPool.run(callback);
417 public String toString() {
418 if (!NO_NAME.equals(friendlyName)) {
419 return MoreObjects.toStringHelper(getClass())
421 .add("friendlyName", friendlyName)
422 // omit lengthy detail, when there's a name
425 return MoreObjects.toStringHelper(getClass())
426 .add("registeredBlocks", registeredBlocks)
430 static final class RegistrationBlock {
431 private final int begin;
432 private final ImmutableList<Entry<Class<?>[], Serializer<?>>> types;
434 RegistrationBlock(int begin, List<Entry<Class<?>[], Serializer<?>>> types) {
436 this.types = ImmutableList.copyOf(types);
443 public ImmutableList<Entry<Class<?>[], Serializer<?>>> types() {
448 public String toString() {
449 return MoreObjects.toStringHelper(getClass())
456 public int hashCode() {
457 return types.hashCode();
460 // Only the registered types are used for equality.
462 public boolean equals(Object obj) {
467 if (obj instanceof RegistrationBlock) {
468 RegistrationBlock that = (RegistrationBlock) obj;
469 return Objects.equals(this.types, that.types);