2 * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.yangtools.yang.data.codec.gson;
10 import com.google.common.annotations.Beta;
11 import com.google.common.base.Stopwatch;
12 import com.google.common.cache.CacheBuilder;
13 import com.google.common.cache.CacheLoader;
14 import com.google.common.cache.LoadingCache;
15 import java.util.List;
16 import java.util.Optional;
17 import org.opendaylight.yangtools.yang.common.QNameModule;
18 import org.opendaylight.yangtools.yang.data.impl.codec.AbstractIntegerStringCodec;
19 import org.opendaylight.yangtools.yang.data.impl.codec.BinaryStringCodec;
20 import org.opendaylight.yangtools.yang.data.impl.codec.BitsStringCodec;
21 import org.opendaylight.yangtools.yang.data.impl.codec.BooleanStringCodec;
22 import org.opendaylight.yangtools.yang.data.impl.codec.DecimalStringCodec;
23 import org.opendaylight.yangtools.yang.data.impl.codec.EnumStringCodec;
24 import org.opendaylight.yangtools.yang.data.impl.codec.StringStringCodec;
25 import org.opendaylight.yangtools.yang.data.util.codec.AbstractCodecFactory;
26 import org.opendaylight.yangtools.yang.data.util.codec.CodecCache;
27 import org.opendaylight.yangtools.yang.data.util.codec.LazyCodecCache;
28 import org.opendaylight.yangtools.yang.data.util.codec.NoopCodecCache;
29 import org.opendaylight.yangtools.yang.data.util.codec.PrecomputedCodecCache;
30 import org.opendaylight.yangtools.yang.data.util.codec.SharedCodecCache;
31 import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
32 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
33 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
34 import org.opendaylight.yangtools.yang.model.api.TypedDataSchemaNode;
35 import org.opendaylight.yangtools.yang.model.api.type.BinaryTypeDefinition;
36 import org.opendaylight.yangtools.yang.model.api.type.BitsTypeDefinition;
37 import org.opendaylight.yangtools.yang.model.api.type.BooleanTypeDefinition;
38 import org.opendaylight.yangtools.yang.model.api.type.DecimalTypeDefinition;
39 import org.opendaylight.yangtools.yang.model.api.type.EmptyTypeDefinition;
40 import org.opendaylight.yangtools.yang.model.api.type.EnumTypeDefinition;
41 import org.opendaylight.yangtools.yang.model.api.type.IdentityrefTypeDefinition;
42 import org.opendaylight.yangtools.yang.model.api.type.InstanceIdentifierTypeDefinition;
43 import org.opendaylight.yangtools.yang.model.api.type.Int16TypeDefinition;
44 import org.opendaylight.yangtools.yang.model.api.type.Int32TypeDefinition;
45 import org.opendaylight.yangtools.yang.model.api.type.Int64TypeDefinition;
46 import org.opendaylight.yangtools.yang.model.api.type.Int8TypeDefinition;
47 import org.opendaylight.yangtools.yang.model.api.type.StringTypeDefinition;
48 import org.opendaylight.yangtools.yang.model.api.type.Uint16TypeDefinition;
49 import org.opendaylight.yangtools.yang.model.api.type.Uint32TypeDefinition;
50 import org.opendaylight.yangtools.yang.model.api.type.Uint64TypeDefinition;
51 import org.opendaylight.yangtools.yang.model.api.type.Uint8TypeDefinition;
52 import org.opendaylight.yangtools.yang.model.api.type.UnionTypeDefinition;
53 import org.opendaylight.yangtools.yang.model.api.type.UnknownTypeDefinition;
54 import org.slf4j.Logger;
55 import org.slf4j.LoggerFactory;
58 * Factory for creating JSON equivalents of codecs. Each instance of this object is bound to
59 * a particular {@link SchemaContext}, but can be reused by multiple {@link JSONNormalizedNodeStreamWriter}s.
62 * There are multiple implementations available, each with distinct thread-safety, CPU/memory trade-offs and reuse
63 * characteristics. See {@link #getShared(SchemaContext)}, {@link #getPrecomputed(SchemaContext)},
64 * {@link #createLazy(SchemaContext)} and {@link #createSimple(SchemaContext)} for details.
67 public final class JSONCodecFactory extends AbstractCodecFactory<JSONCodec<?>> {
68 private static final class EagerCacheLoader extends CacheLoader<SchemaContext, JSONCodecFactory> {
70 public JSONCodecFactory load(final SchemaContext key) {
71 final Stopwatch sw = Stopwatch.createStarted();
72 final LazyCodecCache<JSONCodec<?>> lazyCache = new LazyCodecCache<>();
73 final JSONCodecFactory lazy = new JSONCodecFactory(key, lazyCache);
74 final int visitedLeaves = requestCodecsForChildren(lazy, key);
77 final PrecomputedCodecCache<JSONCodec<?>> cache = lazyCache.toPrecomputed();
78 LOG.debug("{} leaf nodes resulted in {} simple and {} complex codecs in {}", visitedLeaves,
79 cache.simpleSize(), cache.complexSize(), sw);
80 return new JSONCodecFactory(key, cache);
83 private static int requestCodecsForChildren(final JSONCodecFactory lazy, final DataNodeContainer parent) {
85 for (DataSchemaNode child : parent.getChildNodes()) {
86 if (child instanceof TypedDataSchemaNode) {
87 lazy.codecFor((TypedDataSchemaNode) child);
89 } else if (child instanceof DataNodeContainer) {
90 ret += requestCodecsForChildren(lazy, (DataNodeContainer) child);
98 private static final Logger LOG = LoggerFactory.getLogger(JSONCodecFactory.class);
100 // Weak keys to retire the entry when SchemaContext goes away
101 private static final LoadingCache<SchemaContext, JSONCodecFactory> PRECOMPUTED = CacheBuilder.newBuilder()
102 .weakKeys().build(new EagerCacheLoader());
104 // Weak keys to retire the entry when SchemaContext goes away and to force identity-based lookup
105 private static final LoadingCache<SchemaContext, JSONCodecFactory> SHARED = CacheBuilder.newBuilder()
106 .weakKeys().build(new CacheLoader<SchemaContext, JSONCodecFactory>() {
108 public JSONCodecFactory load(final SchemaContext key) {
109 return new JSONCodecFactory(key, new SharedCodecCache<>());
113 private final JSONCodec<?> iidCodec;
115 JSONCodecFactory(final SchemaContext context, final CodecCache<JSONCodec<?>> cache) {
116 super(context, cache);
117 iidCodec = new JSONStringInstanceIdentifierCodec(context, this);
121 * Get a thread-safe, eagerly-caching {@link JSONCodecFactory} for a SchemaContext. This method can, and will,
122 * return the same instance as long as the associated SchemaContext is present. Returned object can be safely
123 * used by multiple threads concurrently. If the SchemaContext instance does not have a cached instance
124 * of {@link JSONCodecFactory}, it will be completely precomputed before this method will return.
127 * Choosing this implementation is appropriate when the memory overhead of keeping a full codec tree is not as
128 * great a concern as predictable performance. When compared to the implementation returned by
129 * {@link #getShared(SchemaContext)}, this implementation is expected to offer higher performance and have lower
130 * peak memory footprint when most of the SchemaContext is actually in use.
133 * For call sites which do not want to pay the CPU cost of pre-computing this implementation, but still would like
134 * to use it if is available (by being populated by some other caller), you can use
135 * {@link #getPrecomputedIfAvailable(SchemaContext)}.
137 * @param context SchemaContext instance
138 * @return A sharable {@link JSONCodecFactory}
139 * @throws NullPointerException if context is null
141 public static JSONCodecFactory getPrecomputed(final SchemaContext context) {
142 return PRECOMPUTED.getUnchecked(context);
146 * Get a thread-safe, eagerly-caching {@link JSONCodecFactory} for a SchemaContext, if it is available. This
147 * method is a non-blocking equivalent of {@link #getPrecomputed(SchemaContext)} for use in code paths where
148 * the potential of having to pre-compute the implementation is not acceptable. One such scenario is when the
149 * code base wants to opportunistically take advantage of pre-computed version, but is okay with a fallback to
150 * a different implementation.
152 * @param context SchemaContext instance
153 * @return A sharable {@link JSONCodecFactory}, or absent if such an implementation is not available.
154 * @throws NullPointerException if context is null
156 public static Optional<JSONCodecFactory> getPrecomputedIfAvailable(final SchemaContext context) {
157 return Optional.ofNullable(PRECOMPUTED.getIfPresent(context));
161 * Get a thread-safe, lazily-caching {@link JSONCodecFactory} for a SchemaContext. This method can, and will,
162 * return the same instance as long as the associated SchemaContext is present or the factory is not invalidated
163 * by memory pressure. Returned object can be safely used by multiple threads concurrently.
166 * Choosing this implementation is a safe default, as it will not incur prohibitive blocking, nor will it tie up
167 * memory in face of pressure.
169 * @param context SchemaContext instance
170 * @return A sharable {@link JSONCodecFactory}
171 * @throws NullPointerException if context is null
173 public static JSONCodecFactory getShared(final SchemaContext context) {
174 return SHARED.getUnchecked(context);
178 * Create a new thread-unsafe, lazily-caching {@link JSONCodecFactory} for a SchemaContext. This method will
179 * return distinct objects every time it is invoked. Returned object may not be used from multiple threads
183 * This implementation is appropriate for one-off serialization from a single thread. It will aggressively cache
184 * codecs for reuse and will tie them up in memory until the factory is freed.
186 * @param context SchemaContext instance
187 * @return A non-sharable {@link JSONCodecFactory}
188 * @throws NullPointerException if context is null
190 public static JSONCodecFactory createLazy(final SchemaContext context) {
191 return new JSONCodecFactory(context, new LazyCodecCache<>());
195 * Create a simplistic, thread-safe {@link JSONCodecFactory} for a {@link SchemaContext}. This method will return
196 * distinct objects every time it is invoked. Returned object may be use from multiple threads concurrently.
199 * This implementation exists mostly for completeness only, as it does not perform any caching at all and each codec
200 * is computed every time it is requested. This may be useful in extremely constrained environments, where memory
201 * footprint is more critical than performance.
203 * @param context SchemaContext instance
204 * @return A non-sharable {@link JSONCodecFactory}
205 * @throws NullPointerException if context is null.
207 public static JSONCodecFactory createSimple(final SchemaContext context) {
208 return new JSONCodecFactory(context, NoopCodecCache.getInstance());
212 protected JSONCodec<?> binaryCodec(final BinaryTypeDefinition type) {
213 return new QuotedJSONCodec<>(BinaryStringCodec.from(type));
217 protected JSONCodec<?> booleanCodec(final BooleanTypeDefinition type) {
218 return new BooleanJSONCodec(BooleanStringCodec.from(type));
222 protected JSONCodec<?> bitsCodec(final BitsTypeDefinition type) {
223 return new QuotedJSONCodec<>(BitsStringCodec.from(type));
227 protected JSONCodec<?> decimalCodec(final DecimalTypeDefinition type) {
228 return new NumberJSONCodec<>(DecimalStringCodec.from(type));
232 protected JSONCodec<?> emptyCodec(final EmptyTypeDefinition type) {
233 return EmptyJSONCodec.INSTANCE;
237 protected JSONCodec<?> enumCodec(final EnumTypeDefinition type) {
238 return new QuotedJSONCodec<>(EnumStringCodec.from(type));
242 protected JSONCodec<?> identityRefCodec(final IdentityrefTypeDefinition type, final QNameModule module) {
243 return new IdentityrefJSONCodec(getSchemaContext(), module);
247 protected JSONCodec<?> instanceIdentifierCodec(final InstanceIdentifierTypeDefinition type) {
248 // FIXME: there really are two favors, as 'require-instance true' needs to be validated. In order to deal
249 // with that, though, we need access to the current data store.
254 protected JSONCodec<?> int8Codec(final Int8TypeDefinition type) {
255 return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
259 protected JSONCodec<?> int16Codec(final Int16TypeDefinition type) {
260 return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
264 protected JSONCodec<?> int32Codec(final Int32TypeDefinition type) {
265 return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
269 protected JSONCodec<?> int64Codec(final Int64TypeDefinition type) {
270 return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
274 protected JSONCodec<?> stringCodec(final StringTypeDefinition type) {
275 return new QuotedJSONCodec<>(StringStringCodec.from(type));
279 protected JSONCodec<?> uint8Codec(final Uint8TypeDefinition type) {
280 return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
284 protected JSONCodec<?> uint16Codec(final Uint16TypeDefinition type) {
285 return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
289 protected JSONCodec<?> uint32Codec(final Uint32TypeDefinition type) {
290 return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
294 protected JSONCodec<?> uint64Codec(final Uint64TypeDefinition type) {
295 return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
299 protected JSONCodec<?> unionCodec(final UnionTypeDefinition type, final List<JSONCodec<?>> codecs) {
300 return UnionJSONCodec.create(type, codecs);
304 protected JSONCodec<?> unknownCodec(final UnknownTypeDefinition type) {
305 return NullJSONCodec.INSTANCE;