+/*
+ * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
package org.opendaylight.controller.md.sal.dom.store.impl;
import static com.google.common.base.Preconditions.checkArgument;
+import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.opendaylight.controller.md.sal.dom.store.impl.tree.StoreMetadataNode;
import org.opendaylight.controller.md.sal.dom.store.impl.tree.StoreNodeCompositeBuilder;
import org.opendaylight.yangtools.yang.common.QName;
+import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.AugmentationIdentifier;
import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.NodeIdentifier;
import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.NodeIdentifierWithPredicates;
import org.opendaylight.yangtools.yang.data.api.schema.MapNode;
import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNodeContainer;
+import org.opendaylight.yangtools.yang.data.api.schema.OrderedLeafSetNode;
import org.opendaylight.yangtools.yang.data.api.schema.OrderedMapNode;
import org.opendaylight.yangtools.yang.data.api.schema.UnkeyedListEntryNode;
-import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.api.DataContainerNodeBuilder;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.api.NormalizedNodeContainerBuilder;
+import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableAugmentationNodeBuilder;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableChoiceNodeBuilder;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableContainerNodeBuilder;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableLeafSetNodeBuilder;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableMapEntryNodeBuilder;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableMapNodeBuilder;
+import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableOrderedLeafSetNodeBuilder;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableOrderedMapNodeBuilder;
import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableUnkeyedListEntryNodeBuilder;
+import org.opendaylight.yangtools.yang.data.impl.schema.transform.base.AugmentationSchemaProxy;
import org.opendaylight.yangtools.yang.model.api.AugmentationSchema;
import org.opendaylight.yangtools.yang.model.api.AugmentationTarget;
import org.opendaylight.yangtools.yang.model.api.ChoiceCaseNode;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import com.google.common.collect.ImmutableMap;
-import com.google.common.collect.ImmutableSet;
-import com.google.common.collect.ImmutableSet.Builder;
import com.google.common.primitives.UnsignedLong;
public abstract class SchemaAwareApplyOperation implements ModificationApplyOperation {
} else if (schemaNode instanceof ChoiceNode) {
return new ChoiceModificationStrategy((ChoiceNode) schemaNode);
} else if (schemaNode instanceof LeafListSchemaNode) {
- return new LeafSetEntryModificationStrategy((LeafListSchemaNode) schemaNode);
+ return fromLeafListSchemaNode((LeafListSchemaNode) schemaNode);
} else if (schemaNode instanceof LeafSchemaNode) {
return new LeafModificationStrategy((LeafSchemaNode) schemaNode);
}
return new UnorderedMapModificationStrategy(schemaNode);
}
+ private static SchemaAwareApplyOperation fromLeafListSchemaNode(final LeafListSchemaNode schemaNode) {
+ if(schemaNode.isUserOrdered()) {
+ return new OrderedLeafSetModificationStrategy(schemaNode);
+ } else {
+ return new UnorderedLeafSetModificationStrategy(schemaNode);
+ }
+ }
+
+
public static SchemaAwareApplyOperation from(final DataNodeContainer resolvedTree,
final AugmentationTarget augSchemas, final AugmentationIdentifier identifier) {
AugmentationSchema augSchema = null;
protected abstract void verifyWritenStructure(NormalizedNode<?, ?> writenValue);
@Override
- public boolean isApplicable(final NodeModification modification, final Optional<StoreMetadataNode> current) {
+ public void checkApplicable(final InstanceIdentifier path,final NodeModification modification, final Optional<StoreMetadataNode> current) throws DataPreconditionFailedException {
switch (modification.getModificationType()) {
case DELETE:
- return isDeleteApplicable(modification, current);
+ checkDeleteApplicable(modification, current);
case SUBTREE_MODIFIED:
- return isSubtreeModificationApplicable(modification, current);
+ checkSubtreeModificationApplicable(path,modification, current);
+ return;
case WRITE:
- return isWriteApplicable(modification, current);
+ checkWriteApplicable(path,modification, current);
+ return;
case MERGE:
- return isMergeApplicable(modification,current);
+ checkMergeApplicable(path,modification,current);
+ return;
case UNMODIFIED:
- return true;
+ return;
default:
- return false;
+ throw new UnsupportedOperationException("Suplied modification type "+modification.getModificationType()+ "is not supported.");
}
+
}
- private boolean isMergeApplicable(final NodeModification modification, final Optional<StoreMetadataNode> current) {
+ protected void checkMergeApplicable(final InstanceIdentifier path,final NodeModification modification, final Optional<StoreMetadataNode> current) throws DataPreconditionFailedException {
Optional<StoreMetadataNode> original = modification.getOriginal();
if (original.isPresent() && current.isPresent()) {
- return isNotConflicting(original.get(), current.get());
- } else if (current.isPresent()) {
- return true;
+ /*
+ * We need to do conflict detection only and only if the value of leaf changed
+ * before two transactions. If value of leaf is unchanged between two transactions
+ * it should not cause transaction to fail, since result of this merge
+ * leads to same data.
+ */
+ if(!original.get().getData().equals(current.get().getData())) {
+
+ checkNotConflicting(path,original.get(), current.get());
+ }
}
- return true;
}
- protected boolean isWriteApplicable(final NodeModification modification, final Optional<StoreMetadataNode> current) {
+ protected void checkWriteApplicable(final InstanceIdentifier path,final NodeModification modification, final Optional<StoreMetadataNode> current) throws DataPreconditionFailedException {
Optional<StoreMetadataNode> original = modification.getOriginal();
if (original.isPresent() && current.isPresent()) {
- return isNotConflicting(original.get(), current.get());
- } else if (current.isPresent()) {
- return false;
+ checkNotConflicting(path,original.get(), current.get());
+ } else if(original.isPresent()) {
+ throw new DataPreconditionFailedException(path,"Node was deleted by other transaction.");
}
- return true;
-
}
- protected final boolean isNotConflicting(final StoreMetadataNode original, final StoreMetadataNode current) {
- return original.getNodeVersion().equals(current.getNodeVersion())
- && original.getSubtreeVersion().equals(current.getSubtreeVersion());
+ protected static final void checkNotConflicting(final InstanceIdentifier path,final StoreMetadataNode original, final StoreMetadataNode current) throws DataPreconditionFailedException {
+ checkDataPrecondition(path, original.getNodeVersion().equals(current.getNodeVersion()),"Node was replaced by other transaction.");
+ checkDataPrecondition(path,original.getSubtreeVersion().equals(current.getSubtreeVersion()), "Node children was modified by other transaction");
}
- protected abstract boolean isSubtreeModificationApplicable(final NodeModification modification,
- final Optional<StoreMetadataNode> current);
+ protected abstract void checkSubtreeModificationApplicable(InstanceIdentifier path,final NodeModification modification,
+ final Optional<StoreMetadataNode> current) throws DataPreconditionFailedException;
- private boolean isDeleteApplicable(final NodeModification modification, final Optional<StoreMetadataNode> current) {
- // FiXME: Add delete conflict detection.
- return true;
+ private void checkDeleteApplicable(final NodeModification modification, final Optional<StoreMetadataNode> current) {
}
@Override
}
@Override
- protected boolean isSubtreeModificationApplicable(final NodeModification modification,
- final Optional<StoreMetadataNode> current) {
- return false;
+ protected void checkSubtreeModificationApplicable(final InstanceIdentifier path,final NodeModification modification,
+ final Optional<StoreMetadataNode> current) throws DataPreconditionFailedException {
+ throw new DataPreconditionFailedException(path, "Subtree modification is not allowed.");
}
}
}
}
+ @Override
+ protected void checkWriteApplicable(final InstanceIdentifier path, final NodeModification modification,
+ final Optional<StoreMetadataNode> current) throws DataPreconditionFailedException {
+ // FIXME: Implement proper write check for replacement of node container
+ // prerequisite is to have transaction chain available for clients
+ // otherwise this will break chained writes to same node.
+ }
+
@SuppressWarnings("rawtypes")
@Override
protected void verifyWritenStructure(final NormalizedNode<?, ?> writenValue) {
@Override
protected StoreMetadataNode applyWrite(final NodeModification modification,
final Optional<StoreMetadataNode> currentMeta, final UnsignedLong subtreeVersion) {
- //
+
NormalizedNode<?, ?> newValue = modification.getWritenValue();
- UnsignedLong nodeVersion = subtreeVersion;
+ final UnsignedLong nodeVersion;
if (currentMeta.isPresent()) {
nodeVersion = StoreUtils.increase(currentMeta.get().getNodeVersion());
+ } else {
+ nodeVersion = subtreeVersion;
}
- StoreMetadataNode newValueMeta = StoreMetadataNode.createRecursively(newValue, nodeVersion, nodeVersion);
+ final StoreMetadataNode newValueMeta = StoreMetadataNode.createRecursively(newValue, nodeVersion, nodeVersion);
if (!modification.hasAdditionalModifications()) {
return newValueMeta;
}
+
@SuppressWarnings("rawtypes")
- NormalizedNodeContainerBuilder dataBuilder = createBuilder(modification.getIdentifier());
+ NormalizedNodeContainerBuilder dataBuilder = createBuilder(newValue);
StoreNodeCompositeBuilder builder = StoreNodeCompositeBuilder.from(dataBuilder) //
.setNodeVersion(nodeVersion) //
.setSubtreeVersion(subtreeVersion);
- Set<PathArgument> processedPreexisting = applyPreexistingChildren(modification, newValueMeta.getChildren(),
- builder, nodeVersion);
- applyNewChildren(modification, processedPreexisting, builder, nodeVersion);
-
- return builder.build();
-
+ return mutateChildren(modification.getModifications(), newValueMeta, builder, nodeVersion);
}
@Override
@Override
public StoreMetadataNode applySubtreeChange(final NodeModification modification,
final StoreMetadataNode currentMeta, final UnsignedLong subtreeVersion) {
+ // Bump subtree version to its new target
+ final UnsignedLong updatedSubtreeVersion = StoreUtils.increase(currentMeta.getSubtreeVersion());
- UnsignedLong updatedSubtreeVersion = StoreUtils.increase(currentMeta.getSubtreeVersion());
@SuppressWarnings("rawtypes")
- NormalizedNodeContainerBuilder dataBuilder = createBuilder(modification.getIdentifier());
- StoreNodeCompositeBuilder builder = StoreNodeCompositeBuilder.from(dataBuilder)
+ NormalizedNodeContainerBuilder dataBuilder = createBuilder(currentMeta.getData());
+ StoreNodeCompositeBuilder builder = StoreNodeCompositeBuilder.from(dataBuilder, currentMeta)
.setIdentifier(modification.getIdentifier()).setNodeVersion(currentMeta.getNodeVersion())
.setSubtreeVersion(updatedSubtreeVersion);
- // We process preexisting nodes
- Set<PathArgument> processedPreexisting = applyPreexistingChildren(modification, currentMeta.getChildren(),
- builder, updatedSubtreeVersion);
- applyNewChildren(modification, processedPreexisting, builder, updatedSubtreeVersion);
- return builder.build();
+
+ return mutateChildren(modification.getModifications(), currentMeta, builder, updatedSubtreeVersion);
}
- private void applyNewChildren(final NodeModification modification, final Set<PathArgument> ignore,
- final StoreNodeCompositeBuilder builder, final UnsignedLong subtreeVersion) {
- for (NodeModification childModification : modification.getModifications()) {
- PathArgument childIdentifier = childModification.getIdentifier();
- // We skip allready processed modifications
- if (ignore.contains(childIdentifier)) {
- continue;
- }
+ private StoreMetadataNode mutateChildren(final Iterable<NodeModification> modifications, final StoreMetadataNode meta,
+ final StoreNodeCompositeBuilder builder, final UnsignedLong nodeVersion) {
- builder.addIfPresent(resolveChildOperation(childIdentifier) //
- .apply(childModification, Optional.<StoreMetadataNode> absent(), subtreeVersion));
- }
- }
+ for (NodeModification mod : modifications) {
+ final PathArgument id = mod.getIdentifier();
+ final Optional<StoreMetadataNode> cm = meta.getChild(id);
- private Set<PathArgument> applyPreexistingChildren(final NodeModification modification,
- final Iterable<StoreMetadataNode> children, final StoreNodeCompositeBuilder nodeBuilder,
- final UnsignedLong subtreeVersion) {
- Builder<PathArgument> processedModifications = ImmutableSet.<PathArgument> builder();
- for (StoreMetadataNode childMeta : children) {
- PathArgument childIdentifier = childMeta.getIdentifier();
- // We retrieve Child modification metadata
- Optional<NodeModification> childModification = modification.getChild(childIdentifier);
- // Node is modified
- if (childModification.isPresent()) {
- processedModifications.add(childIdentifier);
- Optional<StoreMetadataNode> result = resolveChildOperation(childIdentifier) //
- .apply(childModification.get(), Optional.of(childMeta), subtreeVersion);
- nodeBuilder.addIfPresent(result);
+ Optional<StoreMetadataNode> result = resolveChildOperation(id).apply(mod, cm, nodeVersion);
+ if (result.isPresent()) {
+ builder.add(result.get());
} else {
- // Child is unmodified - reuse existing metadata and data
- // snapshot
- nodeBuilder.add(childMeta);
+ builder.remove(id);
}
}
- return processedModifications.build();
+
+ return builder.build();
}
@Override
- protected boolean isSubtreeModificationApplicable(final NodeModification modification,
- final Optional<StoreMetadataNode> current) {
- if (false == current.isPresent()) {
- return false;
- }
- boolean result = true;
+ protected void checkSubtreeModificationApplicable(final InstanceIdentifier path,final NodeModification modification,
+ final Optional<StoreMetadataNode> current) throws DataPreconditionFailedException {
+ checkDataPrecondition(path, current.isPresent(), "Node was deleted by other transaction.");
+ checkChildPreconditions(path,modification,current);
+
+ }
+
+ private void checkChildPreconditions(final InstanceIdentifier path, final NodeModification modification, final Optional<StoreMetadataNode> current) throws DataPreconditionFailedException {
StoreMetadataNode currentMeta = current.get();
for (NodeModification childMod : modification.getModifications()) {
PathArgument childId = childMod.getIdentifier();
Optional<StoreMetadataNode> childMeta = currentMeta.getChild(childId);
- result &= resolveChildOperation(childId).isApplicable(childMod, childMeta);
+ InstanceIdentifier childPath = StoreUtils.append(path, childId);
+ resolveChildOperation(childId).checkApplicable(childPath,childMod, childMeta);
+ }
+ }
+
+ @Override
+ protected void checkMergeApplicable(final InstanceIdentifier path, final NodeModification modification,
+ final Optional<StoreMetadataNode> current) throws DataPreconditionFailedException {
+ if(current.isPresent()) {
+ checkChildPreconditions(path,modification,current);
}
- return result;
}
@SuppressWarnings("rawtypes")
- protected abstract NormalizedNodeContainerBuilder createBuilder(PathArgument identifier);
+ protected abstract NormalizedNodeContainerBuilder createBuilder(NormalizedNode<?, ?> original);
}
public static abstract class DataNodeContainerModificationStrategy<T extends DataNodeContainer> extends
@Override
@SuppressWarnings("rawtypes")
- protected abstract DataContainerNodeBuilder createBuilder(PathArgument identifier);
+ protected abstract DataContainerNodeBuilder createBuilder(NormalizedNode<?, ?> original);
@Override
public String toString() {
@Override
@SuppressWarnings("rawtypes")
- protected DataContainerNodeBuilder createBuilder(final PathArgument identifier) {
- // TODO Auto-generated method stub
- checkArgument(identifier instanceof NodeIdentifier);
- return ImmutableContainerNodeBuilder.create().withNodeIdentifier((NodeIdentifier) identifier);
+ protected DataContainerNodeBuilder createBuilder(final NormalizedNode<?, ?> original) {
+ checkArgument(original instanceof ContainerNode);
+ return ImmutableContainerNodeBuilder.create((ContainerNode) original);
}
-
}
public static class UnkeyedListItemModificationStrategy extends
@Override
@SuppressWarnings("rawtypes")
- protected DataContainerNodeBuilder createBuilder(final PathArgument identifier) {
- checkArgument(identifier instanceof NodeIdentifier);
- return ImmutableUnkeyedListEntryNodeBuilder.create().withNodeIdentifier((NodeIdentifier) identifier);
+ protected DataContainerNodeBuilder createBuilder(final NormalizedNode<?, ?> original) {
+ checkArgument(original instanceof UnkeyedListEntryNode);
+ return ImmutableUnkeyedListEntryNodeBuilder.create((UnkeyedListEntryNode) original);
}
-
}
public static class AugmentationModificationStrategy extends
DataNodeContainerModificationStrategy<AugmentationSchema> {
protected AugmentationModificationStrategy(final AugmentationSchema schema, final DataNodeContainer resolved) {
- super(schema, AugmentationNode.class);
- // FIXME: Use resolved children instead of unresolved.
-
+ super(createAugmentProxy(schema,resolved), AugmentationNode.class);
}
@Override
- protected DataContainerNodeBuilder createBuilder(final PathArgument identifier) {
- return Builders.augmentationBuilder().withNodeIdentifier((AugmentationIdentifier) identifier);
+ @SuppressWarnings("rawtypes")
+ protected DataContainerNodeBuilder createBuilder(final NormalizedNode<?, ?> original) {
+ checkArgument(original instanceof AugmentationNode);
+ return ImmutableAugmentationNodeBuilder.create((AugmentationNode) original);
}
-
}
public static class ChoiceModificationStrategy extends NormalizedNodeContainerModificationStrategy {
@Override
@SuppressWarnings("rawtypes")
- protected DataContainerNodeBuilder createBuilder(final PathArgument identifier) {
- checkArgument(identifier instanceof NodeIdentifier);
- return ImmutableChoiceNodeBuilder.create().withNodeIdentifier((NodeIdentifier) identifier);
+ protected DataContainerNodeBuilder createBuilder(final NormalizedNode<?, ?> original) {
+ checkArgument(original instanceof org.opendaylight.yangtools.yang.data.api.schema.ChoiceNode);
+ return ImmutableChoiceNodeBuilder.create((org.opendaylight.yangtools.yang.data.api.schema.ChoiceNode) original);
}
-
}
public static class ListEntryModificationStrategy extends DataNodeContainerModificationStrategy<ListSchemaNode> {
@Override
@SuppressWarnings("rawtypes")
- protected final DataContainerNodeBuilder createBuilder(final PathArgument identifier) {
- return ImmutableMapEntryNodeBuilder.create().withNodeIdentifier((NodeIdentifierWithPredicates) identifier);
+ protected final DataContainerNodeBuilder createBuilder(final NormalizedNode<?, ?> original) {
+ checkArgument(original instanceof MapEntryNode);
+ return ImmutableMapEntryNodeBuilder.create((MapEntryNode) original);
}
-
}
- public static class LeafSetModificationStrategy extends NormalizedNodeContainerModificationStrategy {
+ public static class UnorderedLeafSetModificationStrategy extends NormalizedNodeContainerModificationStrategy {
private final Optional<ModificationApplyOperation> entryStrategy;
@SuppressWarnings({ "unchecked", "rawtypes" })
- protected LeafSetModificationStrategy(final LeafListSchemaNode schema) {
+ protected UnorderedLeafSetModificationStrategy(final LeafListSchemaNode schema) {
super((Class) LeafSetNode.class);
entryStrategy = Optional.<ModificationApplyOperation> of(new LeafSetEntryModificationStrategy(schema));
}
@SuppressWarnings("rawtypes")
@Override
- protected NormalizedNodeContainerBuilder createBuilder(final PathArgument identifier) {
- return ImmutableLeafSetNodeBuilder.create().withNodeIdentifier((NodeIdentifier) identifier);
+ protected NormalizedNodeContainerBuilder createBuilder(final NormalizedNode<?, ?> original) {
+ checkArgument(original instanceof LeafSetNode<?>);
+ return ImmutableLeafSetNodeBuilder.create((LeafSetNode<?>) original);
}
@Override
}
return Optional.absent();
}
+ }
+
+ public static class OrderedLeafSetModificationStrategy extends NormalizedNodeContainerModificationStrategy {
+ private final Optional<ModificationApplyOperation> entryStrategy;
+
+ @SuppressWarnings({ "unchecked", "rawtypes" })
+ protected OrderedLeafSetModificationStrategy(final LeafListSchemaNode schema) {
+ super((Class) LeafSetNode.class);
+ entryStrategy = Optional.<ModificationApplyOperation> of(new LeafSetEntryModificationStrategy(schema));
+ }
+
+ @SuppressWarnings("rawtypes")
+ @Override
+ protected NormalizedNodeContainerBuilder createBuilder(final NormalizedNode<?, ?> original) {
+ checkArgument(original instanceof OrderedLeafSetNode<?>);
+ return ImmutableOrderedLeafSetNodeBuilder.create((OrderedLeafSetNode<?>) original);
+ }
+
+ @Override
+ public Optional<ModificationApplyOperation> getChild(final PathArgument identifier) {
+ if (identifier instanceof NodeWithValue) {
+ return entryStrategy;
+ }
+ return Optional.absent();
+ }
}
public static class UnkeyedListModificationStrategy extends SchemaAwareApplyOperation {
}
@Override
- protected boolean isSubtreeModificationApplicable(final NodeModification modification,
- final Optional<StoreMetadataNode> current) {
- return false;
+ protected void checkSubtreeModificationApplicable(final InstanceIdentifier path,final NodeModification modification,
+ final Optional<StoreMetadataNode> current) throws DataPreconditionFailedException {
+ throw new DataPreconditionFailedException(path, "Subtree modification is not allowed.");
}
}
@SuppressWarnings("rawtypes")
@Override
- protected NormalizedNodeContainerBuilder createBuilder(final PathArgument identifier) {
- return ImmutableMapNodeBuilder.create().withNodeIdentifier((NodeIdentifier) identifier);
+ protected NormalizedNodeContainerBuilder createBuilder(final NormalizedNode<?, ?> original) {
+ checkArgument(original instanceof MapNode);
+ return ImmutableMapNodeBuilder.create((MapNode) original);
}
@Override
@SuppressWarnings("rawtypes")
@Override
- protected NormalizedNodeContainerBuilder createBuilder(final PathArgument identifier) {
- return ImmutableOrderedMapNodeBuilder.create().withNodeIdentifier((NodeIdentifier) identifier);
+ protected NormalizedNodeContainerBuilder createBuilder(final NormalizedNode<?, ?> original) {
+ checkArgument(original instanceof OrderedMapNode);
+ return ImmutableOrderedMapNodeBuilder.create((OrderedMapNode) original);
}
@Override
}
+ public static AugmentationSchema createAugmentProxy(final AugmentationSchema schema, final DataNodeContainer resolved) {
+ Set<DataSchemaNode> realChildSchemas = new HashSet<>();
+ for(DataSchemaNode augChild : schema.getChildNodes()) {
+ realChildSchemas.add(resolved.getDataChildByName(augChild.getQName()));
+ }
+ return new AugmentationSchemaProxy(schema, realChildSchemas);
+ }
+
+ public static boolean checkDataPrecondition(final InstanceIdentifier path, final boolean condition, final String message) throws DataPreconditionFailedException {
+ if(!condition) {
+ throw new DataPreconditionFailedException(path, message);
+ }
+ return condition;
+ }
+
}