binding/mdsal-binding-dom-adapter/src/main/java/org/opendaylight/mdsal/binding/dom/adapter/BindingToNormalizedNodeCodec.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   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
   7  */
   8 package org.opendaylight.mdsal.binding.dom.adapter;
   9
  10 import static com.google.common.base.Preconditions.checkArgument;
  11 import static com.google.common.base.Preconditions.checkState;
  12 import static java.util.Objects.requireNonNull;
  13
  14 import com.google.common.cache.CacheBuilder;
  15 import com.google.common.cache.CacheLoader;
  16 import com.google.common.cache.LoadingCache;
  17 import com.google.common.collect.ImmutableBiMap;
  18 import com.google.common.collect.ImmutableSet;
  19 import com.google.common.collect.Iterators;
  20 import java.lang.reflect.Method;
  21 import java.time.Instant;
  22 import java.util.AbstractMap.SimpleEntry;
  23 import java.util.Collection;
  24 import java.util.HashSet;
  25 import java.util.Map.Entry;
  26 import java.util.Optional;
  27 import java.util.Set;
  28 import java.util.concurrent.TimeUnit;
  29 import java.util.function.Function;
  30 import java.util.stream.Collectors;
  31 import org.eclipse.jdt.annotation.NonNull;
  32 import org.opendaylight.mdsal.binding.api.DataTreeIdentifier;
  33 import org.opendaylight.mdsal.binding.dom.codec.api.BindingCodecTree;
  34 import org.opendaylight.mdsal.binding.dom.codec.api.BindingCodecTreeFactory;
  35 import org.opendaylight.mdsal.binding.dom.codec.api.BindingCodecTreeNode;
  36 import org.opendaylight.mdsal.binding.dom.codec.api.BindingDataObjectCodecTreeNode;
  37 import org.opendaylight.mdsal.binding.dom.codec.api.BindingLazyContainerNode;
  38 import org.opendaylight.mdsal.binding.dom.codec.api.BindingNormalizedNodeSerializer;
  39 import org.opendaylight.mdsal.binding.dom.codec.impl.BindingNormalizedNodeCodecRegistry;
  40 import org.opendaylight.mdsal.binding.dom.codec.impl.MissingSchemaException;
  41 import org.opendaylight.mdsal.binding.generator.api.ClassLoadingStrategy;
  42 import org.opendaylight.mdsal.binding.generator.util.BindingRuntimeContext;
  43 import org.opendaylight.mdsal.binding.spec.naming.BindingMapping;
  44 import org.opendaylight.mdsal.binding.spec.reflect.BindingReflections;
  45 import org.opendaylight.mdsal.dom.api.DOMDataTreeIdentifier;
  46 import org.opendaylight.mdsal.dom.api.DOMSchemaService;
  47 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  48 import org.opendaylight.yangtools.yang.binding.Action;
  49 import org.opendaylight.yangtools.yang.binding.DataContainer;
  50 import org.opendaylight.yangtools.yang.binding.DataObject;
  51 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  52 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier.PathArgument;
  53 import org.opendaylight.yangtools.yang.binding.Notification;
  54 import org.opendaylight.yangtools.yang.binding.RpcInput;
  55 import org.opendaylight.yangtools.yang.binding.RpcOutput;
  56 import org.opendaylight.yangtools.yang.binding.RpcService;
  57 import org.opendaylight.yangtools.yang.common.QNameModule;
  58 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  59 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
  60 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  61 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  62 import org.opendaylight.yangtools.yang.data.impl.codec.DeserializationException;
  63 import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
  64 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
  65 import org.opendaylight.yangtools.yang.model.api.ActionDefinition;
  66 import org.opendaylight.yangtools.yang.model.api.DocumentedNode.WithStatus;
  67 import org.opendaylight.yangtools.yang.model.api.ListSchemaNode;
  68 import org.opendaylight.yangtools.yang.model.api.Module;
  69 import org.opendaylight.yangtools.yang.model.api.NotificationDefinition;
  70 import org.opendaylight.yangtools.yang.model.api.RpcDefinition;
  71 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  72 import org.opendaylight.yangtools.yang.model.api.SchemaContextListener;
  73 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  74 import org.slf4j.Logger;
  75 import org.slf4j.LoggerFactory;
  76
  77 /**
  78  * A combinations of {@link BindingCodecTreeFactory} and {@link BindingNormalizedNodeSerializer}, with internal
  79  * caching of instance identifiers.
  80  *
  81  * <p>
  82  * NOTE: this class is non-final to allow controller adapter migration without duplicated code.
  83  */
  84 public class BindingToNormalizedNodeCodec implements BindingCodecTreeFactory,
  85         BindingNormalizedNodeSerializer, SchemaContextListener, AutoCloseable {
  86
  87     private static final long WAIT_DURATION_SEC = 5;
  88     private static final Logger LOG = LoggerFactory.getLogger(BindingToNormalizedNodeCodec.class);
  89
  90     private final LoadingCache<InstanceIdentifier<?>, YangInstanceIdentifier> iiCache = CacheBuilder.newBuilder()
  91             .softValues().build(new CacheLoader<InstanceIdentifier<?>, YangInstanceIdentifier>() {
  92                 @Override
  93                 public YangInstanceIdentifier load(final InstanceIdentifier<?> key) {
  94                     return toYangInstanceIdentifierBlocking(key);
  95                 }
  96             });
  97     private final BindingNormalizedNodeCodecRegistry codecRegistry;
  98     private final ClassLoadingStrategy classLoadingStrategy;
  99     private final FutureSchema futureSchema;
 100     private ListenerRegistration<?> listenerRegistration;
 101
 102     public BindingToNormalizedNodeCodec(final ClassLoadingStrategy classLoadingStrategy,
 103             final BindingNormalizedNodeCodecRegistry codecRegistry) {
 104         this(classLoadingStrategy, codecRegistry, false);
 105     }
 106
 107     public BindingToNormalizedNodeCodec(final ClassLoadingStrategy classLoadingStrategy,
 108             final BindingNormalizedNodeCodecRegistry codecRegistry, final boolean waitForSchema) {
 109         this.classLoadingStrategy = requireNonNull(classLoadingStrategy, "classLoadingStrategy");
 110         this.codecRegistry = requireNonNull(codecRegistry, "codecRegistry");
 111         this.futureSchema = FutureSchema.create(WAIT_DURATION_SEC, TimeUnit.SECONDS, waitForSchema);
 112     }
 113
 114     public static BindingToNormalizedNodeCodec newInstance(final ClassLoadingStrategy classLoadingStrategy,
 115             final DOMSchemaService schemaService) {
 116         final BindingNormalizedNodeCodecRegistry codecRegistry = new BindingNormalizedNodeCodecRegistry();
 117         BindingToNormalizedNodeCodec instance = new BindingToNormalizedNodeCodec(
 118                 classLoadingStrategy, codecRegistry, true);
 119         instance.listenerRegistration = schemaService.registerSchemaContextListener(instance);
 120         return instance;
 121     }
 122
 123     protected YangInstanceIdentifier toYangInstanceIdentifierBlocking(
 124             final InstanceIdentifier<? extends DataObject> binding) {
 125         try {
 126             return codecRegistry.toYangInstanceIdentifier(binding);
 127         } catch (final MissingSchemaException e) {
 128             waitForSchema(decompose(binding), e);
 129             return codecRegistry.toYangInstanceIdentifier(binding);
 130         }
 131     }
 132
 133     /**
 134      * Translates supplied Binding Instance Identifier into NormalizedNode
 135      * instance identifier.
 136      *
 137      * @param binding
 138      *            Binding Instance Identifier
 139      * @return DOM Instance Identifier
 140      * @throws IllegalArgumentException
 141      *             If supplied Instance Identifier is not valid.
 142      */
 143     public final YangInstanceIdentifier toNormalized(final InstanceIdentifier<? extends DataObject> binding) {
 144         return codecRegistry.toYangInstanceIdentifier(binding);
 145     }
 146
 147     @Override
 148     public final YangInstanceIdentifier toYangInstanceIdentifier(final InstanceIdentifier<?> binding) {
 149         return codecRegistry.toYangInstanceIdentifier(binding);
 150     }
 151
 152     protected YangInstanceIdentifier toYangInstanceIdentifierCached(final InstanceIdentifier<?> binding) {
 153         return iiCache.getUnchecked(binding);
 154     }
 155
 156     @Override
 157     public final <T extends DataObject> Entry<YangInstanceIdentifier, NormalizedNode<?, ?>> toNormalizedNode(
 158             final InstanceIdentifier<T> path, final T data) {
 159         try {
 160             return codecRegistry.toNormalizedNode(path, data);
 161         } catch (final MissingSchemaException e) {
 162             waitForSchema(decompose(path), e);
 163             return codecRegistry.toNormalizedNode(path, data);
 164         }
 165     }
 166
 167     /**
 168      * Converts Binding Map.Entry to DOM Map.Entry.
 169      *
 170      * <p>
 171      * Same as {@link #toNormalizedNode(InstanceIdentifier, DataObject)}.
 172      *
 173      * @param binding Map Entry with InstanceIdentifier as key and DataObject as value.
 174      * @return DOM Map Entry with {@link YangInstanceIdentifier} as key and {@link NormalizedNode}
 175      *         as value.
 176      */
 177     @SuppressWarnings({"unchecked", "rawtypes"})
 178     public final Entry<YangInstanceIdentifier, NormalizedNode<?, ?>> toNormalizedNode(
 179             final Entry<InstanceIdentifier<? extends DataObject>, DataObject> binding) {
 180         return toNormalizedNode((InstanceIdentifier) binding.getKey(), binding.getValue());
 181     }
 182
 183     @Override
 184     public final Entry<InstanceIdentifier<?>, DataObject> fromNormalizedNode(final YangInstanceIdentifier path,
 185             final NormalizedNode<?, ?> data) {
 186         return codecRegistry.fromNormalizedNode(path, data);
 187     }
 188
 189     @Override
 190     public final Notification fromNormalizedNodeNotification(final SchemaPath path, final ContainerNode data) {
 191         return codecRegistry.fromNormalizedNodeNotification(path, data);
 192     }
 193
 194     @Override
 195     public final Notification fromNormalizedNodeNotification(final SchemaPath path, final ContainerNode data,
 196             final Instant eventInstant) {
 197         return codecRegistry.fromNormalizedNodeNotification(path, data, eventInstant);
 198     }
 199
 200     @Override
 201     public final DataObject fromNormalizedNodeRpcData(final SchemaPath path, final ContainerNode data) {
 202         return codecRegistry.fromNormalizedNodeRpcData(path, data);
 203     }
 204
 205     @Override
 206     public <T extends RpcInput> T fromNormalizedNodeActionInput(final Class<? extends Action<?, ?, ?>> action,
 207             final ContainerNode input) {
 208         return codecRegistry.fromNormalizedNodeActionInput(action, input);
 209     }
 210
 211     @Override
 212     public <T extends RpcOutput> T fromNormalizedNodeActionOutput(final Class<? extends Action<?, ?, ?>> action,
 213             final ContainerNode output) {
 214         return codecRegistry.fromNormalizedNodeActionOutput(action, output);
 215     }
 216
 217     @Override
 218     public final InstanceIdentifier<?> fromYangInstanceIdentifier(final YangInstanceIdentifier dom) {
 219         return codecRegistry.fromYangInstanceIdentifier(dom);
 220     }
 221
 222     @Override
 223     public final ContainerNode toNormalizedNodeNotification(final Notification data) {
 224         return codecRegistry.toNormalizedNodeNotification(data);
 225     }
 226
 227     @Override
 228     public final ContainerNode toNormalizedNodeRpcData(final DataContainer data) {
 229         return codecRegistry.toNormalizedNodeRpcData(data);
 230     }
 231
 232     @Override
 233     public ContainerNode toNormalizedNodeActionInput(final Class<? extends Action<?, ?, ?>> action,
 234             final RpcInput input) {
 235         return codecRegistry.toNormalizedNodeActionInput(action, input);
 236     }
 237
 238     @Override
 239     public ContainerNode toNormalizedNodeActionOutput(final Class<? extends Action<?, ?, ?>> action,
 240             final RpcOutput output) {
 241         return codecRegistry.toNormalizedNodeActionOutput(action, output);
 242     }
 243
 244     @Override
 245     public BindingLazyContainerNode<RpcInput> toLazyNormalizedNodeActionInput(
 246             final Class<? extends Action<?, ?, ?>> action, final NodeIdentifier identifier, final RpcInput input) {
 247         return codecRegistry.toLazyNormalizedNodeActionInput(action, identifier, input);
 248     }
 249
 250     @Override
 251     public BindingLazyContainerNode<RpcOutput> toLazyNormalizedNodeActionOutput(
 252             final Class<? extends Action<?, ?, ?>> action, final NodeIdentifier identifier, final RpcOutput output) {
 253         return codecRegistry.toLazyNormalizedNodeActionOutput(action, identifier, output);
 254     }
 255
 256     /**
 257      * Returns a Binding-Aware instance identifier from normalized
 258      * instance-identifier if it is possible to create representation.
 259      *
 260      * <p>
 261      * Returns Optional.empty for cases where target is mixin node except
 262      * augmentation.
 263      */
 264     public final Optional<InstanceIdentifier<? extends DataObject>> toBinding(final YangInstanceIdentifier normalized)
 265                     throws DeserializationException {
 266         try {
 267             return Optional.ofNullable(codecRegistry.fromYangInstanceIdentifier(normalized));
 268         } catch (final IllegalArgumentException e) {
 269             return Optional.empty();
 270         }
 271     }
 272
 273     public final Optional<Entry<InstanceIdentifier<? extends DataObject>, DataObject>> toBinding(
 274             final @NonNull Entry<YangInstanceIdentifier, ? extends NormalizedNode<?, ?>> normalized)
 275                     throws DeserializationException {
 276         try {
 277             /*
 278              * This cast is required, due to generics behaviour in openjdk / oracle javac.
 279              *
 280              * <p>
 281              * InstanceIdentifier has definition InstanceIdentifier<T extends DataObject>,
 282              * this means '?' is always  <? extends DataObject>. Eclipse compiler
 283              * is able to determine this relationship and treats
 284              * Entry<InstanceIdentifier<?>, DataObject> and Entry<InstanceIdentifier<? extends DataObject, DataObject>
 285              * as assignable. However openjdk / oracle javac treats this two types
 286              * as incompatible and issues a compile error.
 287              *
 288              * <p>
 289              * It is safe to lose generic information and cast it to other generic signature.
 290              */
 291             @SuppressWarnings("unchecked")
 292             final Entry<InstanceIdentifier<? extends DataObject>, DataObject> binding = Entry.class.cast(
 293                     codecRegistry.fromNormalizedNode(normalized.getKey(), normalized.getValue()));
 294             return Optional.ofNullable(binding);
 295         } catch (final IllegalArgumentException e) {
 296             return Optional.empty();
 297         }
 298     }
 299
 300     @Override
 301     public void onGlobalContextUpdated(final SchemaContext context) {
 302         final BindingRuntimeContext runtimeContext = BindingRuntimeContext.create(classLoadingStrategy, context);
 303         codecRegistry.onBindingRuntimeContextUpdated(runtimeContext);
 304         futureSchema.onRuntimeContextUpdated(runtimeContext);
 305     }
 306
 307     /**
 308      * Deprecated.
 309      *
 310      * @deprecated Use {@link BindingNormalizedNodeCodecRegistry#deserializeFunction} instead.
 311      */
 312     @Deprecated
 313     public final <T extends DataObject> Function<Optional<NormalizedNode<?, ?>>, Optional<T>> deserializeFunction(
 314             final InstanceIdentifier<T> path) {
 315         return codecRegistry.deserializeFunction(path)::apply;
 316     }
 317
 318     public final BindingNormalizedNodeCodecRegistry getCodecRegistry() {
 319         return codecRegistry;
 320     }
 321
 322     @Override
 323     public void close() {
 324         if (listenerRegistration != null) {
 325             listenerRegistration.close();
 326         }
 327     }
 328
 329     public final BindingNormalizedNodeCodecRegistry getCodecFactory() {
 330         return codecRegistry;
 331     }
 332
 333     // FIXME: This should be probably part of Binding Runtime context
 334     public final ImmutableBiMap<Method, SchemaPath> getRpcMethodToSchemaPath(final Class<? extends RpcService> key) {
 335         final Module module = getModuleBlocking(key);
 336         final ImmutableBiMap.Builder<Method, SchemaPath> ret = ImmutableBiMap.builder();
 337         try {
 338             for (final RpcDefinition rpcDef : module.getRpcs()) {
 339                 final Method method = findRpcMethod(key, rpcDef);
 340                 ret.put(method, rpcDef.getPath());
 341             }
 342         } catch (final NoSuchMethodException e) {
 343             throw new IllegalStateException("Rpc defined in model does not have representation in generated class.", e);
 344         }
 345         return ret.build();
 346     }
 347
 348     protected ImmutableBiMap<Method, RpcDefinition> getRpcMethodToSchema(final Class<? extends RpcService> key) {
 349         final Module module = getModuleBlocking(key);
 350         final ImmutableBiMap.Builder<Method, RpcDefinition> ret = ImmutableBiMap.builder();
 351         try {
 352             for (final RpcDefinition rpcDef : module.getRpcs()) {
 353                 final Method method = findRpcMethod(key, rpcDef);
 354                 ret.put(method, rpcDef);
 355             }
 356         } catch (final NoSuchMethodException e) {
 357             throw new IllegalStateException("Rpc defined in model does not have representation in generated class.", e);
 358         }
 359         return ret.build();
 360     }
 361
 362     private Module getModuleBlocking(final Class<?> modeledClass) {
 363         final QNameModule moduleName = BindingReflections.getQNameModule(modeledClass);
 364         BindingRuntimeContext localRuntimeContext = runtimeContext();
 365         Module module = localRuntimeContext == null ? null :
 366             localRuntimeContext.getSchemaContext().findModule(moduleName).orElse(null);
 367         if (module == null && futureSchema.waitForSchema(moduleName)) {
 368             localRuntimeContext = runtimeContext();
 369             checkState(localRuntimeContext != null, "BindingRuntimeContext is not available.");
 370             module = localRuntimeContext.getSchemaContext().findModule(moduleName).orElse(null);
 371         }
 372         if (module != null) {
 373             return module;
 374         }
 375
 376         LOG.debug("Schema for {} is not available; expected module name: {}; BindingRuntimeContext: {}",
 377                 modeledClass, moduleName, localRuntimeContext);
 378         throw new IllegalStateException(String.format("Schema for %s is not available; expected module name: %s; "
 379                 + "full BindingRuntimeContext available in debug log", modeledClass, moduleName));
 380     }
 381
 382     private void waitForSchema(final Collection<Class<?>> binding, final MissingSchemaException exception) {
 383         LOG.warn("Blocking thread to wait for schema convergence updates for {} {}", futureSchema.getDuration(),
 384             futureSchema.getUnit());
 385         if (!futureSchema.waitForSchema(binding)) {
 386             throw exception;
 387         }
 388     }
 389
 390     private Method findRpcMethod(final Class<? extends RpcService> key, final RpcDefinition rpcDef)
 391             throws NoSuchMethodException {
 392         final String methodName = BindingMapping.getMethodName(rpcDef.getQName());
 393         final Class<?> inputClz = runtimeContext().getClassForSchema(rpcDef.getInput());
 394         return key.getMethod(methodName, inputClz);
 395     }
 396
 397     @Override
 398     public final BindingCodecTree create(final BindingRuntimeContext context) {
 399         return codecRegistry.create(context);
 400     }
 401
 402     @Override
 403     public final BindingCodecTree create(final SchemaContext context, final Class<?>... bindingClasses) {
 404         return codecRegistry.create(context, bindingClasses);
 405     }
 406
 407     protected @NonNull Entry<InstanceIdentifier<?>, BindingDataObjectCodecTreeNode<?>> getSubtreeCodec(
 408             final YangInstanceIdentifier domIdentifier) {
 409
 410         final BindingCodecTree currentCodecTree = codecRegistry.getCodecContext();
 411         final InstanceIdentifier<?> bindingPath = codecRegistry.fromYangInstanceIdentifier(domIdentifier);
 412         checkArgument(bindingPath != null);
 413         /**
 414          * If we are able to deserialize YANG instance identifier, getSubtreeCodec must
 415          * return non-null value.
 416          */
 417         final BindingDataObjectCodecTreeNode<?> codecContext = currentCodecTree.getSubtreeCodec(bindingPath);
 418         return new SimpleEntry<>(bindingPath, codecContext);
 419     }
 420
 421     @SuppressWarnings("unchecked")
 422     public final Set<Class<? extends Notification>> getNotificationClasses(final Set<SchemaPath> interested) {
 423         final Set<Class<? extends Notification>> result = new HashSet<>();
 424         final BindingRuntimeContext runtimeContext = runtimeContext();
 425         for (final NotificationDefinition notification : runtimeContext.getSchemaContext().getNotifications()) {
 426             if (interested.contains(notification.getPath())) {
 427                 try {
 428                     result.add((Class<? extends Notification>) runtimeContext.getClassForSchema(notification));
 429                 } catch (final IllegalStateException e) {
 430                     // Ignore
 431                     LOG.warn("Class for {} is currently not known.", notification.getPath(), e);
 432                 }
 433             }
 434         }
 435         return result;
 436     }
 437
 438     SchemaPath getActionPath(final Class<? extends Action<?, ?, ?>> type) {
 439         final ActionDefinition schema = runtimeContext().getActionDefinition(type);
 440         checkArgument(schema != null, "Failed to find schema for %s", type);
 441         return schema.getPath();
 442     }
 443
 444     private BindingRuntimeContext runtimeContext() {
 445         return futureSchema.runtimeContext();
 446     }
 447
 448     private static Collection<Class<?>> decompose(final InstanceIdentifier<?> path) {
 449         return ImmutableSet.copyOf(Iterators.transform(path.getPathArguments().iterator(), PathArgument::getType));
 450     }
 451
 452     protected NormalizedNode<?, ?> instanceIdentifierToNode(final YangInstanceIdentifier parentPath) {
 453         return ImmutableNodes.fromInstanceId(runtimeContext().getSchemaContext(), parentPath);
 454     }
 455
 456     /**
 457      * This method creates an empty list container of a particular type.
 458      *
 459      * @deprecated This method is not generally useful, as empty lists do not convey information in YANG (they are
 460      *             equivalent to non-present lists). It also leaks implementation details to a broader scope and should
 461      *             never have been public in the first place.
 462      */
 463     @Deprecated
 464     public NormalizedNode<?, ?> getDefaultNodeFor(final YangInstanceIdentifier parentMapPath) {
 465         final BindingCodecTreeNode mapCodec = requireNonNull(
 466                 codecRegistry.getCodecContext().getSubtreeCodec(parentMapPath),
 467                 "Codec not found for yang instance identifier: " + parentMapPath);
 468         final WithStatus schema = mapCodec.getSchema();
 469         if (schema instanceof ListSchemaNode) {
 470             final ListSchemaNode castedSchema = (ListSchemaNode) schema;
 471             return castedSchema.isUserOrdered() ? Builders.orderedMapBuilder(castedSchema).build()
 472                     : Builders.mapBuilder(castedSchema).build();
 473         }
 474         throw new IllegalArgumentException("Path does not point to list schema node");
 475     }
 476
 477     protected Collection<DOMDataTreeIdentifier> toDOMDataTreeIdentifiers(
 478             final Collection<DataTreeIdentifier<?>> subtrees) {
 479         return subtrees.stream().map(this::toDOMDataTreeIdentifier).collect(Collectors.toSet());
 480     }
 481
 482     protected DOMDataTreeIdentifier toDOMDataTreeIdentifier(final DataTreeIdentifier<?> path) {
 483         final YangInstanceIdentifier domPath = toYangInstanceIdentifierBlocking(path.getRootIdentifier());
 484         return new DOMDataTreeIdentifier(path.getDatastoreType(), domPath);
 485     }
 486 }