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.esotericsoftware.kryo.serializers.CompatibleFieldSerializer;
27 import com.google.common.base.MoreObjects;
28 import com.google.common.collect.ImmutableList;
29 import org.apache.commons.lang3.tuple.Pair;
30 import org.objenesis.strategy.StdInstantiatorStrategy;
31 import org.slf4j.Logger;
32 import org.slf4j.LoggerFactory;
34 import java.io.ByteArrayInputStream;
35 import java.io.InputStream;
36 import java.io.OutputStream;
37 import java.nio.ByteBuffer;
38 import java.util.ArrayList;
39 import java.util.Arrays;
40 import java.util.List;
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 * Maximum allowed buffer size.
61 public static final int MAX_BUFFER_SIZE = 100 * 1000 * 1000;
64 * ID to use if this KryoNamespace does not define registration id.
66 public static final int FLOATING_ID = -1;
69 * Smallest ID free to use for user defined registrations.
71 public static final int INITIAL_ID = 16;
73 static final String NO_NAME = "(no name)";
75 private static final Logger LOGGER = LoggerFactory.getLogger(Namespace.class);
78 * Default Kryo namespace.
80 public static final Namespace DEFAULT = builder().build();
82 private final KryoPool kryoPool = new KryoPool.Builder(this)
86 private final KryoOutputPool kryoOutputPool = new KryoOutputPool();
87 private final KryoInputPool kryoInputPool = new KryoInputPool();
89 private final ImmutableList<RegistrationBlock> registeredBlocks;
91 private final ClassLoader classLoader;
92 private final boolean compatible;
93 private final boolean registrationRequired;
94 private final String friendlyName;
97 * KryoNamespace builder.
100 public static final class Builder {
101 private int blockHeadId = INITIAL_ID;
102 private List<Pair<Class<?>[], Serializer<?>>> types = new ArrayList<>();
103 private List<RegistrationBlock> blocks = new ArrayList<>();
104 private ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
105 private boolean registrationRequired = true;
106 private boolean compatible = false;
109 * Builds a {@link Namespace} instance.
111 * @return KryoNamespace
113 public Namespace build() {
114 return build(NO_NAME);
118 * Builds a {@link Namespace} instance.
120 * @param friendlyName friendly name for the namespace
121 * @return KryoNamespace
123 public Namespace build(String friendlyName) {
124 if (!types.isEmpty()) {
125 blocks.add(new RegistrationBlock(this.blockHeadId, types));
127 return new Namespace(blocks, classLoader, registrationRequired, compatible, friendlyName).populate(1);
131 * Sets the next Kryo registration Id for following register entries.
133 * @param id Kryo registration Id
135 * @see Kryo#register(Class, Serializer, int)
137 public Builder nextId(final int id) {
138 if (!types.isEmpty()) {
139 if (id != FLOATING_ID && id < blockHeadId + types.size()) {
141 if (LOGGER.isWarnEnabled()) {
142 LOGGER.warn("requested nextId {} could potentially overlap "
143 + "with existing registrations {}+{} ",
144 id, blockHeadId, types.size(), new RuntimeException());
147 blocks.add(new RegistrationBlock(this.blockHeadId, types));
148 types = new ArrayList<>();
150 this.blockHeadId = id;
155 * Registers serializer for the given set of classes.
157 * When multiple classes are registered with an explicitly provided serializer, the namespace guarantees
158 * all instances will be serialized with the same type ID.
160 * @param classes list of classes to register
161 * @param serializer serializer to use for the class
164 public Builder register(Serializer<?> serializer, final Class<?>... classes) {
165 types.add(Pair.of(classes, requireNonNull(serializer)));
170 * Sets the namespace class loader.
172 * @param classLoader the namespace class loader
173 * @return the namespace builder
175 public Builder setClassLoader(ClassLoader classLoader) {
176 this.classLoader = classLoader;
181 * Sets whether backwards/forwards compatible versioned serialization is enabled.
183 * When compatible serialization is enabled, the {@link CompatibleFieldSerializer} will be set as the
184 * default serializer for types that do not otherwise explicitly specify a serializer.
186 * @param compatible whether versioned serialization is enabled
189 public Builder setCompatible(boolean compatible) {
190 this.compatible = compatible;
195 * Sets the registrationRequired flag.
197 * @param registrationRequired Kryo's registrationRequired flag
199 * @see Kryo#setRegistrationRequired(boolean)
201 public Builder setRegistrationRequired(boolean registrationRequired) {
202 this.registrationRequired = registrationRequired;
208 * Creates a new {@link Namespace} builder.
212 public static Builder builder() {
213 return new Builder();
217 * Creates a Kryo instance pool.
219 * @param registeredTypes types to register
220 * @param registrationRequired whether registration is required
221 * @param compatible whether compatible serialization is enabled
222 * @param friendlyName friendly name for the namespace
225 final List<RegistrationBlock> registeredTypes,
226 ClassLoader classLoader,
227 boolean registrationRequired,
229 String friendlyName) {
230 this.registeredBlocks = ImmutableList.copyOf(registeredTypes);
231 this.registrationRequired = registrationRequired;
232 this.classLoader = classLoader;
233 this.compatible = compatible;
234 this.friendlyName = requireNonNull(friendlyName);
238 * Populates the Kryo pool.
240 * @param instances to add to the pool
243 public Namespace populate(int instances) {
245 for (int i = 0; i < instances; ++i) {
252 * Serializes given object to byte array using Kryo instance in pool.
254 * Note: Serialized bytes must be smaller than {@link #MAX_BUFFER_SIZE}.
256 * @param obj Object to serialize
257 * @return serialized bytes
259 public byte[] serialize(final Object obj) {
260 return serialize(obj, DEFAULT_BUFFER_SIZE);
264 * Serializes given object to byte array using Kryo instance in pool.
266 * @param obj Object to serialize
267 * @param bufferSize maximum size of serialized bytes
268 * @return serialized bytes
270 public byte[] serialize(final Object obj, final int bufferSize) {
271 return kryoOutputPool.run(output -> {
272 return kryoPool.run(kryo -> {
273 kryo.writeClassAndObject(output, obj);
275 return output.getByteArrayOutputStream().toByteArray();
281 * Serializes given object to byte buffer using Kryo instance in pool.
283 * @param obj Object to serialize
284 * @param buffer to write to
286 public void serialize(final Object obj, final ByteBuffer buffer) {
287 ByteBufferOutput out = new ByteBufferOutput(buffer);
288 Kryo kryo = borrow();
290 kryo.writeClassAndObject(out, obj);
298 * Serializes given object to OutputStream using Kryo instance in pool.
300 * @param obj Object to serialize
301 * @param stream to write to
303 public void serialize(final Object obj, final OutputStream stream) {
304 serialize(obj, stream, DEFAULT_BUFFER_SIZE);
308 * Serializes given object to OutputStream using Kryo instance in pool.
310 * @param obj Object to serialize
311 * @param stream to write to
312 * @param bufferSize size of the buffer in front of the stream
314 public void serialize(final Object obj, final OutputStream stream, final int bufferSize) {
315 ByteBufferOutput out = new ByteBufferOutput(stream, bufferSize);
316 Kryo kryo = borrow();
318 kryo.writeClassAndObject(out, obj);
326 * Deserializes given byte array to Object using Kryo instance in pool.
328 * @param bytes serialized bytes
329 * @param <T> deserialized Object type
330 * @return deserialized Object
332 public <T> T deserialize(final byte[] bytes) {
333 return kryoInputPool.run(input -> {
334 input.setInputStream(new ByteArrayInputStream(bytes));
335 return kryoPool.run(kryo -> {
336 @SuppressWarnings("unchecked")
337 T obj = (T) kryo.readClassAndObject(input);
340 }, DEFAULT_BUFFER_SIZE);
344 * Deserializes given byte buffer to Object using Kryo instance in pool.
346 * @param buffer input with serialized bytes
347 * @param <T> deserialized Object type
348 * @return deserialized Object
350 public <T> T deserialize(final ByteBuffer buffer) {
351 ByteBufferInput in = new ByteBufferInput(buffer);
352 Kryo kryo = borrow();
354 @SuppressWarnings("unchecked")
355 T obj = (T) kryo.readClassAndObject(in);
363 * Deserializes given InputStream to an Object using Kryo instance in pool.
365 * @param stream input stream
366 * @param <T> deserialized Object type
367 * @return deserialized Object
369 public <T> T deserialize(final InputStream stream) {
370 return deserialize(stream, DEFAULT_BUFFER_SIZE);
374 * Deserializes given InputStream to an Object using Kryo instance in pool.
376 * @param stream input stream
377 * @param <T> deserialized Object type
378 * @param bufferSize size of the buffer in front of the stream
379 * @return deserialized Object
381 public <T> T deserialize(final InputStream stream, final int bufferSize) {
382 ByteBufferInput in = new ByteBufferInput(stream, bufferSize);
383 Kryo kryo = borrow();
385 @SuppressWarnings("unchecked")
386 T obj = (T) kryo.readClassAndObject(in);
393 private String friendlyName() {
398 * Gets the number of classes registered in this Kryo namespace.
400 * @return size of namespace
403 return (int) registeredBlocks.stream()
404 .flatMap(block -> block.types().stream())
409 * Creates a Kryo instance.
411 * @return Kryo instance
414 public Kryo create() {
415 LOGGER.trace("Creating Kryo instance for {}", this);
416 Kryo kryo = new Kryo();
417 kryo.setClassLoader(classLoader);
418 kryo.setRegistrationRequired(registrationRequired);
420 // If compatible serialization is enabled, override the default serializer.
422 kryo.setDefaultSerializer(CompatibleFieldSerializer::new);
425 // TODO rethink whether we want to use StdInstantiatorStrategy
426 kryo.setInstantiatorStrategy(
427 new Kryo.DefaultInstantiatorStrategy(new StdInstantiatorStrategy()));
429 for (RegistrationBlock block : registeredBlocks) {
430 int id = block.begin();
431 if (id == FLOATING_ID) {
432 id = kryo.getNextRegistrationId();
434 for (Pair<Class<?>[], Serializer<?>> entry : block.types()) {
435 register(kryo, entry.getLeft(), entry.getRight(), id++);
442 * Register {@code type} and {@code serializer} to {@code kryo} instance.
444 * @param kryo Kryo instance
445 * @param types types to register
446 * @param serializer Specific serializer to register or null to use default.
447 * @param id type registration id to use
449 private void register(Kryo kryo, Class<?>[] types, Serializer<?> serializer, int id) {
450 Registration existing = kryo.getRegistration(id);
451 if (existing != null) {
452 boolean matches = false;
453 for (Class<?> type : types) {
454 if (existing.getType() == type) {
461 LOGGER.error("{}: Failed to register {} as {}, {} was already registered.",
462 friendlyName(), types, id, existing.getType());
464 throw new IllegalStateException(String.format(
465 "Failed to register %s as %s, %s was already registered.",
466 Arrays.toString(types), id, existing.getType()));
468 // falling through to register call for now.
469 // Consider skipping, if there's reasonable
470 // way to compare serializer equivalence.
473 for (Class<?> type : types) {
474 Registration r = null;
475 if (serializer == null) {
476 r = kryo.register(type, id);
477 } else if (type.isInterface()) {
478 kryo.addDefaultSerializer(type, serializer);
480 r = kryo.register(type, serializer, id);
483 if (r.getId() != id) {
484 LOGGER.debug("{}: {} already registered as {}. Skipping {}.",
485 friendlyName(), r.getType(), r.getId(), id);
487 LOGGER.trace("{} registered as {}", r.getType(), r.getId());
493 public Kryo borrow() {
494 return kryoPool.borrow();
498 public void release(Kryo kryo) {
499 kryoPool.release(kryo);
503 public <T> T run(KryoCallback<T> callback) {
504 return kryoPool.run(callback);
508 public String toString() {
509 if (!NO_NAME.equals(friendlyName)) {
510 return MoreObjects.toStringHelper(getClass())
512 .add("friendlyName", friendlyName)
513 // omit lengthy detail, when there's a name
516 return MoreObjects.toStringHelper(getClass())
517 .add("registeredBlocks", registeredBlocks)
521 static final class RegistrationBlock {
522 private final int begin;
523 private final ImmutableList<Pair<Class<?>[], Serializer<?>>> types;
525 RegistrationBlock(int begin, List<Pair<Class<?>[], Serializer<?>>> types) {
527 this.types = ImmutableList.copyOf(types);
534 public ImmutableList<Pair<Class<?>[], Serializer<?>>> types() {
539 public String toString() {
540 return MoreObjects.toStringHelper(getClass())
547 public int hashCode() {
548 return types.hashCode();
551 // Only the registered types are used for equality.
553 public boolean equals(Object obj) {
558 if (obj instanceof RegistrationBlock) {
559 RegistrationBlock that = (RegistrationBlock) obj;
560 return Objects.equals(this.types, that.types);