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 classes to be serialized using Kryo default serializer.
157 * @param expectedTypes list of classes
160 public Builder register(final Class<?>... expectedTypes) {
161 for (Class<?> clazz : expectedTypes) {
162 types.add(Pair.of(new Class<?>[]{clazz}, null));
168 * Registers serializer for the given set of classes.
170 * When multiple classes are registered with an explicitly provided serializer, the namespace guarantees
171 * all instances will be serialized with the same type ID.
173 * @param classes list of classes to register
174 * @param serializer serializer to use for the class
177 public Builder register(Serializer<?> serializer, final Class<?>... classes) {
178 types.add(Pair.of(classes, requireNonNull(serializer)));
183 * Sets the namespace class loader.
185 * @param classLoader the namespace class loader
186 * @return the namespace builder
188 public Builder setClassLoader(ClassLoader classLoader) {
189 this.classLoader = classLoader;
194 * Sets whether backwards/forwards compatible versioned serialization is enabled.
196 * When compatible serialization is enabled, the {@link CompatibleFieldSerializer} will be set as the
197 * default serializer for types that do not otherwise explicitly specify a serializer.
199 * @param compatible whether versioned serialization is enabled
202 public Builder setCompatible(boolean compatible) {
203 this.compatible = compatible;
208 * Sets the registrationRequired flag.
210 * @param registrationRequired Kryo's registrationRequired flag
212 * @see Kryo#setRegistrationRequired(boolean)
214 public Builder setRegistrationRequired(boolean registrationRequired) {
215 this.registrationRequired = registrationRequired;
221 * Creates a new {@link Namespace} builder.
225 public static Builder builder() {
226 return new Builder();
230 * Creates a Kryo instance pool.
232 * @param registeredTypes types to register
233 * @param registrationRequired whether registration is required
234 * @param compatible whether compatible serialization is enabled
235 * @param friendlyName friendly name for the namespace
238 final List<RegistrationBlock> registeredTypes,
239 ClassLoader classLoader,
240 boolean registrationRequired,
242 String friendlyName) {
243 this.registeredBlocks = ImmutableList.copyOf(registeredTypes);
244 this.registrationRequired = registrationRequired;
245 this.classLoader = classLoader;
246 this.compatible = compatible;
247 this.friendlyName = requireNonNull(friendlyName);
251 * Populates the Kryo pool.
253 * @param instances to add to the pool
256 public Namespace populate(int instances) {
258 for (int i = 0; i < instances; ++i) {
265 * Serializes given object to byte array using Kryo instance in pool.
267 * Note: Serialized bytes must be smaller than {@link #MAX_BUFFER_SIZE}.
269 * @param obj Object to serialize
270 * @return serialized bytes
272 public byte[] serialize(final Object obj) {
273 return serialize(obj, DEFAULT_BUFFER_SIZE);
277 * Serializes given object to byte array using Kryo instance in pool.
279 * @param obj Object to serialize
280 * @param bufferSize maximum size of serialized bytes
281 * @return serialized bytes
283 public byte[] serialize(final Object obj, final int bufferSize) {
284 return kryoOutputPool.run(output -> {
285 return kryoPool.run(kryo -> {
286 kryo.writeClassAndObject(output, obj);
288 return output.getByteArrayOutputStream().toByteArray();
294 * Serializes given object to byte buffer using Kryo instance in pool.
296 * @param obj Object to serialize
297 * @param buffer to write to
299 public void serialize(final Object obj, final ByteBuffer buffer) {
300 ByteBufferOutput out = new ByteBufferOutput(buffer);
301 Kryo kryo = borrow();
303 kryo.writeClassAndObject(out, obj);
311 * Serializes given object to OutputStream using Kryo instance in pool.
313 * @param obj Object to serialize
314 * @param stream to write to
316 public void serialize(final Object obj, final OutputStream stream) {
317 serialize(obj, stream, DEFAULT_BUFFER_SIZE);
321 * Serializes given object to OutputStream using Kryo instance in pool.
323 * @param obj Object to serialize
324 * @param stream to write to
325 * @param bufferSize size of the buffer in front of the stream
327 public void serialize(final Object obj, final OutputStream stream, final int bufferSize) {
328 ByteBufferOutput out = new ByteBufferOutput(stream, bufferSize);
329 Kryo kryo = borrow();
331 kryo.writeClassAndObject(out, obj);
339 * Deserializes given byte array to Object using Kryo instance in pool.
341 * @param bytes serialized bytes
342 * @param <T> deserialized Object type
343 * @return deserialized Object
345 public <T> T deserialize(final byte[] bytes) {
346 return kryoInputPool.run(input -> {
347 input.setInputStream(new ByteArrayInputStream(bytes));
348 return kryoPool.run(kryo -> {
349 @SuppressWarnings("unchecked")
350 T obj = (T) kryo.readClassAndObject(input);
353 }, DEFAULT_BUFFER_SIZE);
357 * Deserializes given byte buffer to Object using Kryo instance in pool.
359 * @param buffer input with serialized bytes
360 * @param <T> deserialized Object type
361 * @return deserialized Object
363 public <T> T deserialize(final ByteBuffer buffer) {
364 ByteBufferInput in = new ByteBufferInput(buffer);
365 Kryo kryo = borrow();
367 @SuppressWarnings("unchecked")
368 T obj = (T) kryo.readClassAndObject(in);
376 * Deserializes given InputStream to an Object using Kryo instance in pool.
378 * @param stream input stream
379 * @param <T> deserialized Object type
380 * @return deserialized Object
382 public <T> T deserialize(final InputStream stream) {
383 return deserialize(stream, DEFAULT_BUFFER_SIZE);
387 * Deserializes given InputStream to an Object using Kryo instance in pool.
389 * @param stream input stream
390 * @param <T> deserialized Object type
391 * @param bufferSize size of the buffer in front of the stream
392 * @return deserialized Object
394 public <T> T deserialize(final InputStream stream, final int bufferSize) {
395 ByteBufferInput in = new ByteBufferInput(stream, bufferSize);
396 Kryo kryo = borrow();
398 @SuppressWarnings("unchecked")
399 T obj = (T) kryo.readClassAndObject(in);
406 private String friendlyName() {
411 * Gets the number of classes registered in this Kryo namespace.
413 * @return size of namespace
416 return (int) registeredBlocks.stream()
417 .flatMap(block -> block.types().stream())
422 * Creates a Kryo instance.
424 * @return Kryo instance
427 public Kryo create() {
428 LOGGER.trace("Creating Kryo instance for {}", this);
429 Kryo kryo = new Kryo();
430 kryo.setClassLoader(classLoader);
431 kryo.setRegistrationRequired(registrationRequired);
433 // If compatible serialization is enabled, override the default serializer.
435 kryo.setDefaultSerializer(CompatibleFieldSerializer::new);
438 // TODO rethink whether we want to use StdInstantiatorStrategy
439 kryo.setInstantiatorStrategy(
440 new Kryo.DefaultInstantiatorStrategy(new StdInstantiatorStrategy()));
442 for (RegistrationBlock block : registeredBlocks) {
443 int id = block.begin();
444 if (id == FLOATING_ID) {
445 id = kryo.getNextRegistrationId();
447 for (Pair<Class<?>[], Serializer<?>> entry : block.types()) {
448 register(kryo, entry.getLeft(), entry.getRight(), id++);
455 * Register {@code type} and {@code serializer} to {@code kryo} instance.
457 * @param kryo Kryo instance
458 * @param types types to register
459 * @param serializer Specific serializer to register or null to use default.
460 * @param id type registration id to use
462 private void register(Kryo kryo, Class<?>[] types, Serializer<?> serializer, int id) {
463 Registration existing = kryo.getRegistration(id);
464 if (existing != null) {
465 boolean matches = false;
466 for (Class<?> type : types) {
467 if (existing.getType() == type) {
474 LOGGER.error("{}: Failed to register {} as {}, {} was already registered.",
475 friendlyName(), types, id, existing.getType());
477 throw new IllegalStateException(String.format(
478 "Failed to register %s as %s, %s was already registered.",
479 Arrays.toString(types), id, existing.getType()));
481 // falling through to register call for now.
482 // Consider skipping, if there's reasonable
483 // way to compare serializer equivalence.
486 for (Class<?> type : types) {
487 Registration r = null;
488 if (serializer == null) {
489 r = kryo.register(type, id);
490 } else if (type.isInterface()) {
491 kryo.addDefaultSerializer(type, serializer);
493 r = kryo.register(type, serializer, id);
496 if (r.getId() != id) {
497 LOGGER.debug("{}: {} already registered as {}. Skipping {}.",
498 friendlyName(), r.getType(), r.getId(), id);
500 LOGGER.trace("{} registered as {}", r.getType(), r.getId());
506 public Kryo borrow() {
507 return kryoPool.borrow();
511 public void release(Kryo kryo) {
512 kryoPool.release(kryo);
516 public <T> T run(KryoCallback<T> callback) {
517 return kryoPool.run(callback);
521 public String toString() {
522 if (!NO_NAME.equals(friendlyName)) {
523 return MoreObjects.toStringHelper(getClass())
525 .add("friendlyName", friendlyName)
526 // omit lengthy detail, when there's a name
529 return MoreObjects.toStringHelper(getClass())
530 .add("registeredBlocks", registeredBlocks)
534 static final class RegistrationBlock {
535 private final int begin;
536 private final ImmutableList<Pair<Class<?>[], Serializer<?>>> types;
538 RegistrationBlock(int begin, List<Pair<Class<?>[], Serializer<?>>> types) {
540 this.types = ImmutableList.copyOf(types);
547 public ImmutableList<Pair<Class<?>[], Serializer<?>>> types() {
552 public String toString() {
553 return MoreObjects.toStringHelper(getClass())
560 public int hashCode() {
561 return types.hashCode();
564 // Only the registered types are used for equality.
566 public boolean equals(Object obj) {
571 if (obj instanceof RegistrationBlock) {
572 RegistrationBlock that = (RegistrationBlock) obj;
573 return Objects.equals(this.types, that.types);