package org.opendaylight.yangtools.yang.data.codec.gson;
import com.google.common.annotations.Beta;
-import com.google.common.base.Preconditions;
+import com.google.common.base.Optional;
+import com.google.common.base.Stopwatch;
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
-
-import org.opendaylight.yangtools.yang.data.impl.codec.TypeDefinitionAwareCodec;
+import java.util.List;
+import org.opendaylight.yangtools.yang.common.QNameModule;
+import org.opendaylight.yangtools.yang.data.impl.codec.AbstractIntegerStringCodec;
+import org.opendaylight.yangtools.yang.data.impl.codec.BinaryStringCodec;
+import org.opendaylight.yangtools.yang.data.impl.codec.BitsStringCodec;
+import org.opendaylight.yangtools.yang.data.impl.codec.BooleanStringCodec;
+import org.opendaylight.yangtools.yang.data.impl.codec.DecimalStringCodec;
+import org.opendaylight.yangtools.yang.data.impl.codec.EnumStringCodec;
+import org.opendaylight.yangtools.yang.data.impl.codec.StringStringCodec;
+import org.opendaylight.yangtools.yang.data.util.codec.AbstractCodecFactory;
+import org.opendaylight.yangtools.yang.data.util.codec.CodecCache;
+import org.opendaylight.yangtools.yang.data.util.codec.LazyCodecCache;
+import org.opendaylight.yangtools.yang.data.util.codec.NoopCodecCache;
+import org.opendaylight.yangtools.yang.data.util.codec.PrecomputedCodecCache;
+import org.opendaylight.yangtools.yang.data.util.codec.SharedCodecCache;
+import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
+import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
import org.opendaylight.yangtools.yang.model.api.SchemaContext;
-import org.opendaylight.yangtools.yang.model.api.TypeDefinition;
-import org.opendaylight.yangtools.yang.model.api.type.LeafrefTypeDefinition;
-import org.opendaylight.yangtools.yang.model.util.IdentityrefType;
-import org.opendaylight.yangtools.yang.model.util.InstanceIdentifierType;
+import org.opendaylight.yangtools.yang.model.api.TypedSchemaNode;
+import org.opendaylight.yangtools.yang.model.api.type.BinaryTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.BitsTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.BooleanTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.DecimalTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.EmptyTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.EnumTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.IdentityrefTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.InstanceIdentifierTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.IntegerTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.StringTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.UnionTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.UnknownTypeDefinition;
+import org.opendaylight.yangtools.yang.model.api.type.UnsignedIntegerTypeDefinition;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Factory for creating JSON equivalents of codecs. Each instance of this object is bound to
* a particular {@link SchemaContext}, but can be reused by multiple {@link JSONNormalizedNodeStreamWriter}s.
+ *
+ * There are multiple implementations available, each with distinct thread-safety, CPU/memory trade-offs and reuse
+ * characteristics. See {@link #getShared(SchemaContext)}, {@link #getPrecomputed(SchemaContext)},
+ * {@link #createLazy(SchemaContext)} and {@link #createSimple(SchemaContext)} for details.
*/
@Beta
-public final class JSONCodecFactory {
- private static final Logger LOG = LoggerFactory.getLogger(JSONCodecFactory.class);
- private static final JSONCodec<Object> LEAFREF_DEFAULT_CODEC = new JSONLeafrefCodec();
- private static final JSONCodec<Object> NULL_CODEC = new JSONCodec<Object>() {
+public final class JSONCodecFactory extends AbstractCodecFactory<JSONCodec<?>> {
+ private static final class EagerCacheLoader extends CacheLoader<SchemaContext, JSONCodecFactory> {
@Override
- public Object deserialize(final String input) {
- return null;
- }
+ public JSONCodecFactory load(final SchemaContext key) {
+ final Stopwatch sw = Stopwatch.createStarted();
+ final LazyCodecCache<JSONCodec<?>> lazyCache = new LazyCodecCache<>();
+ final JSONCodecFactory lazy = new JSONCodecFactory(key, lazyCache);
+ final int visitedLeaves = requestCodecsForChildren(lazy, key);
+ sw.stop();
- @Override
- public String serialize(final Object input) {
- return null;
+ final PrecomputedCodecCache<JSONCodec<?>> cache = lazyCache.toPrecomputed();
+ LOG.debug("{} leaf nodes resulted in {} simple and {} complex codecs in {}", visitedLeaves,
+ cache.simpleSize(), cache.complexSize(), sw);
+ return new JSONCodecFactory(key, cache);
}
- @Override
- public boolean needQuotes() {
- return false;
- }
- };
+ private static int requestCodecsForChildren(final JSONCodecFactory lazy, final DataNodeContainer parent) {
+ int ret = 0;
+ for (DataSchemaNode child : parent.getChildNodes()) {
+ if (child instanceof TypedSchemaNode) {
+ lazy.codecFor((TypedSchemaNode) child);
+ ++ret;
+ } else if (child instanceof DataNodeContainer) {
+ ret += requestCodecsForChildren(lazy, (DataNodeContainer) child);
+ }
+ }
- private static TypeDefinition<?> resolveBaseTypeFrom(final TypeDefinition<?> type) {
- TypeDefinition<?> superType = type;
- while (superType.getBaseType() != null) {
- superType = superType.getBaseType();
+ return ret;
}
- return superType;
}
- private final LoadingCache<TypeDefinition<?>, JSONCodec<Object>> codecs =
- CacheBuilder.newBuilder().softValues().build(new CacheLoader<TypeDefinition<?>, JSONCodec<Object>>() {
- @SuppressWarnings("unchecked")
- @Override
- public JSONCodec<Object> load(final TypeDefinition<?> key) throws Exception {
- final TypeDefinition<?> type = resolveBaseTypeFrom(key);
-
- if (type instanceof InstanceIdentifierType) {
- return (JSONCodec<Object>) iidCodec;
- }
- if (type instanceof IdentityrefType) {
- return (JSONCodec<Object>) idrefCodec;
- }
- if (type instanceof LeafrefTypeDefinition) {
- return LEAFREF_DEFAULT_CODEC;
- }
+ private static final Logger LOG = LoggerFactory.getLogger(JSONCodecFactory.class);
- final TypeDefinitionAwareCodec<Object, ? extends TypeDefinition<?>> codec = TypeDefinitionAwareCodec.from(type);
- if (codec == null) {
- LOG.debug("Codec for type \"{}\" is not implemented yet.", type.getQName().getLocalName());
- return NULL_CODEC;
- }
+ // Weak keys to retire the entry when SchemaContext goes away
+ private static final LoadingCache<SchemaContext, JSONCodecFactory> PRECOMPUTED = CacheBuilder.newBuilder()
+ .weakKeys().build(new EagerCacheLoader());
- return AbstractJSONCodec.create(codec);
- }
- });
+ // Weak keys to retire the entry when SchemaContext goes away and to force identity-based lookup
+ private static final LoadingCache<SchemaContext, JSONCodecFactory> SHARED = CacheBuilder.newBuilder()
+ .weakKeys().build(new CacheLoader<SchemaContext, JSONCodecFactory>() {
+ @Override
+ public JSONCodecFactory load(final SchemaContext key) {
+ return new JSONCodecFactory(key, new SharedCodecCache<>());
+ }
+ });
- private final SchemaContext schemaContext;
private final JSONCodec<?> iidCodec;
- private final JSONCodec<?> idrefCodec;
- private JSONCodecFactory(final SchemaContext context) {
- this.schemaContext = Preconditions.checkNotNull(context);
- iidCodec = new JSONStringInstanceIdentifierCodec(context);
- idrefCodec = new JSONStringIdentityrefCodec(context);
+ JSONCodecFactory(final SchemaContext context, final CodecCache<JSONCodec<?>> cache) {
+ super(context, cache);
+ iidCodec = new JSONStringInstanceIdentifierCodec(context, this);
}
/**
*
* @param context SchemaContext to which the factory should be bound
* @return A codec factory instance.
+ *
+ * @deprecated Use {@link #getShared(SchemaContext)} instead.
*/
+ @Deprecated
public static JSONCodecFactory create(final SchemaContext context) {
- return new JSONCodecFactory(context);
+ return getShared(context);
+ }
+
+ /**
+ * Get a thread-safe, eagerly-caching {@link JSONCodecFactory} for a SchemaContext. This method can, and will,
+ * return the same instance as long as the associated SchemaContext is present. Returned object can be safely
+ * used by multiple threads concurrently. If the SchemaContext instance does not have a cached instance
+ * of {@link JSONCodecFactory}, it will be completely precomputed before this method will return.
+ *
+ * Choosing this implementation is appropriate when the memory overhead of keeping a full codec tree is not as
+ * great a concern as predictable performance. When compared to the implementation returned by
+ * {@link #getShared(SchemaContext)}, this implementation is expected to offer higher performance and have lower
+ * peak memory footprint when most of the SchemaContext is actually in use.
+ *
+ * For call sites which do not want to pay the CPU cost of pre-computing this implementation, but still would like
+ * to use it if is available (by being populated by some other caller), you can use
+ * {@link #getPrecomputedIfAvailable(SchemaContext)}.
+ *
+ * @param context SchemaContext instance
+ * @return A sharable {@link JSONCodecFactory}
+ * @throws NullPointerException if context is null
+ */
+ public static JSONCodecFactory getPrecomputed(final SchemaContext context) {
+ return PRECOMPUTED.getUnchecked(context);
+ }
+
+ /**
+ * Get a thread-safe, eagerly-caching {@link JSONCodecFactory} for a SchemaContext, if it is available. This
+ * method is a non-blocking equivalent of {@link #getPrecomputed(SchemaContext)} for use in code paths where
+ * the potential of having to pre-compute the implementation is not acceptable. One such scenario is when the
+ * code base wants to opportunistically take advantage of pre-computed version, but is okay with a fallback to
+ * a different implementation.
+ *
+ * @param context SchemaContext instance
+ * @return A sharable {@link JSONCodecFactory}, or absent if such an implementation is not available.
+ * @throws NullPointerException if context is null
+ */
+ public static Optional<JSONCodecFactory> getPrecomputedIfAvailable(final SchemaContext context) {
+ return Optional.fromNullable(PRECOMPUTED.getIfPresent(context));
+ }
+
+ /**
+ * Get a thread-safe, lazily-caching {@link JSONCodecFactory} for a SchemaContext. This method can, and will,
+ * return the same instance as long as the associated SchemaContext is present or the factory is not invalidated
+ * by memory pressure. Returned object can be safely used by multiple threads concurrently.
+ *
+ * Choosing this implementation is a safe default, as it will not incur prohibitive blocking, nor will it tie up
+ * memory in face of pressure.
+ *
+ * @param context SchemaContext instance
+ * @return A sharable {@link JSONCodecFactory}
+ * @throws NullPointerException if context is null
+ */
+ public static JSONCodecFactory getShared(final SchemaContext context) {
+ return SHARED.getUnchecked(context);
+ }
+
+ /**
+ * Create a new thread-unsafe, lazily-caching {@link JSONCodecFactory} for a SchemaContext. This method will
+ * return distinct objects every time it is invoked. Returned object may not be used from multiple threads
+ * concurrently.
+ *
+ * This implementation is appropriate for one-off serialization from a single thread. It will aggressively cache
+ * codecs for reuse and will tie them up in memory until the factory is freed.
+ *
+ * @param context SchemaContext instance
+ * @return A non-sharable {@link JSONCodecFactory}
+ * @throws NullPointerException if context is null
+ */
+ public static JSONCodecFactory createLazy(final SchemaContext context) {
+ return new JSONCodecFactory(context, new LazyCodecCache<>());
+ }
+
+ /**
+ * Create a simplistic, thread-safe {@link JSONCodecFactory} for a {@link SchemaContext}. This method will return
+ * distinct objects every time it is invoked. Returned object may be use from multiple threads concurrently.
+ *
+ * This implementation exists mostly for completeness only, as it does not perform any caching at all and each codec
+ * is computed every time it is requested. This may be useful in extremely constrained environments, where memory
+ * footprint is more critical than performance.
+ *
+ * @param context SchemaContext instance
+ * @return A non-sharable {@link JSONCodecFactory}
+ * @throws NullPointerException if context is null.
+ */
+ public static JSONCodecFactory createSimple(final SchemaContext context) {
+ return new JSONCodecFactory(context, NoopCodecCache.getInstance());
+ }
+
+ @Override
+ protected JSONCodec<?> binaryCodec(final BinaryTypeDefinition type) {
+ return new QuotedJSONCodec<>(BinaryStringCodec.from(type));
+ }
+
+ @Override
+ protected JSONCodec<?> booleanCodec(final BooleanTypeDefinition type) {
+ return new BooleanJSONCodec(BooleanStringCodec.from(type));
+ }
+
+ @Override
+ protected JSONCodec<?> bitsCodec(final BitsTypeDefinition type) {
+ return new QuotedJSONCodec<>(BitsStringCodec.from(type));
+ }
+
+ @Override
+ protected JSONCodec<?> decimalCodec(final DecimalTypeDefinition type) {
+ return new NumberJSONCodec<>(DecimalStringCodec.from(type));
+ }
+
+ @Override
+ protected JSONCodec<?> emptyCodec(final EmptyTypeDefinition type) {
+ return EmptyJSONCodec.INSTANCE;
+ }
+
+ @Override
+ protected JSONCodec<?> enumCodec(final EnumTypeDefinition type) {
+ return new QuotedJSONCodec<>(EnumStringCodec.from(type));
+ }
+
+ @Override
+ protected JSONCodec<?> identityRefCodec(final IdentityrefTypeDefinition type, final QNameModule module) {
+ return new IdentityrefJSONCodec(getSchemaContext(), module);
+ }
+
+ @Override
+ protected JSONCodec<?> instanceIdentifierCodec(final InstanceIdentifierTypeDefinition type) {
+ // FIXME: there really are two favors, as 'require-instance true' needs to be validated. In order to deal
+ // with that, though, we need access to the current data store.
+ return iidCodec;
+ }
+
+ @Override
+ protected JSONCodec<?> intCodec(final IntegerTypeDefinition type) {
+ return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
+ }
+
+ @Override
+ protected JSONCodec<?> stringCodec(final StringTypeDefinition type) {
+ return new QuotedJSONCodec<>(StringStringCodec.from(type));
+ }
+
+ @Override
+ protected JSONCodec<?> uintCodec(final UnsignedIntegerTypeDefinition type) {
+ return new NumberJSONCodec<>(AbstractIntegerStringCodec.from(type));
}
- SchemaContext getSchemaContext() {
- return schemaContext;
+ @Override
+ protected JSONCodec<?> unionCodec(final UnionTypeDefinition type, final List<JSONCodec<?>> codecs) {
+ return UnionJSONCodec.create(type, codecs);
}
- JSONCodec<Object> codecFor(final TypeDefinition<?> typeDefinition) {
- return codecs.getUnchecked(typeDefinition);
+ @Override
+ protected JSONCodec<?> unknownCodec(final UnknownTypeDefinition type) {
+ return NullJSONCodec.INSTANCE;
}
}