data/yang-data-impl/src/main/java/org/opendaylight/yangtools/yang/data/impl/schema/ImmutableNormalizedNodeStreamWriter.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.yangtools.yang.data.impl.schema;
   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 java.io.IOException;
  15 import java.util.ArrayDeque;
  16 import java.util.Deque;
  17 import javax.xml.transform.dom.DOMSource;
  18 import org.eclipse.jdt.annotation.NonNull;
  19 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
  20 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
  21 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeWithValue;
  22 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  23 import org.opendaylight.yangtools.yang.data.api.schema.LeafNode;
  24 import org.opendaylight.yangtools.yang.data.api.schema.LeafSetEntryNode;
  25 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  26 import org.opendaylight.yangtools.yang.data.api.schema.builder.DataContainerNodeBuilder;
  27 import org.opendaylight.yangtools.yang.data.api.schema.builder.NormalizedNodeBuilder;
  28 import org.opendaylight.yangtools.yang.data.api.schema.builder.NormalizedNodeContainerBuilder;
  29 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  30 import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableLeafSetNodeBuilder;
  31 import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableMapNodeBuilder;
  32 import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableUnkeyedListNodeBuilder;
  33 import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableUserLeafSetNodeBuilder;
  34 import org.opendaylight.yangtools.yang.data.impl.schema.builder.impl.ImmutableUserMapNodeBuilder;
  35 import org.opendaylight.yangtools.yang.data.util.LeafInterner;
  36 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
  37 import org.opendaylight.yangtools.yang.model.api.LeafSchemaNode;
  38
  39 /**
  40  * Implementation of {@link NormalizedNodeStreamWriter}, which constructs immutable instances of
  41  * {@link NormalizedNode}s.
  42  *
  43  * <p>
  44  * This writer supports two modes of behaviour one is using {@link #from(NormalizedNodeResult)} where resulting
  45  * NormalizedNode will be stored in supplied result object.
  46  *
  47  * <p>
  48  * Other mode of operation is using {@link #from(NormalizedNodeContainerBuilder)}, where all created nodes will be
  49  * written to this builder.
  50  *
  51  * <p>
  52  * This class is not final for purposes of customization, normal users should not need to subclass it.
  53  */
  54 public class ImmutableNormalizedNodeStreamWriter implements NormalizedNodeStreamWriter {
  55     private final Deque<NormalizedNode.Builder> builders = new ArrayDeque<>();
  56
  57     private DataSchemaNode nextSchema;
  58
  59     protected ImmutableNormalizedNodeStreamWriter(final NormalizedNode.Builder topLevelBuilder) {
  60         builders.push(topLevelBuilder);
  61     }
  62
  63     protected ImmutableNormalizedNodeStreamWriter(final NormalizationResultHolder holder) {
  64         this(new NormalizationResultBuilder(holder));
  65     }
  66
  67     /**
  68      * Creates a {@link NormalizedNodeStreamWriter} which creates instances of supplied {@link NormalizedNode}s
  69      * and writes them to supplied builder as child nodes.
  70      *
  71      * <p>
  72      * Type of supplied {@link NormalizedNodeContainerBuilder} affects, which events could be emitted in order
  73      * to ensure proper construction of data.
  74      *
  75      * @param builder Builder to which data will be written.
  76      * @return {@link NormalizedNodeStreamWriter} which writes data
  77      */
  78     public static @NonNull NormalizedNodeStreamWriter from(final NormalizedNodeContainerBuilder<?, ?, ?, ?> builder) {
  79         return new ImmutableNormalizedNodeStreamWriter(builder);
  80     }
  81
  82     /**
  83      * Creates a {@link NormalizedNodeStreamWriter} which creates one instance of top-level {@link NormalizedNode}
  84      * (type of NormalizedNode) is determined by first start event.
  85      *
  86      * <p>
  87      * Result is built when {@link #endNode()} associated with that start event is emitted.
  88      *
  89      * <p>
  90      * Writer properly creates also nested {@link NormalizedNode} instances, if their are supported inside the scope
  91      * of the first event.
  92      *
  93      * <p>
  94      * This method is useful for clients, which knows there will be one top-level node written, but does not know which
  95      * type of {@link NormalizedNode} will be written.
  96      *
  97      * @param holder {@link NormalizationResultHolder} object which will hold result value.
  98      * @return {@link NormalizedNodeStreamWriter} which will write item to supplied result holder.
  99      */
 100     public static @NonNull NormalizedNodeStreamWriter from(final NormalizationResultHolder holder) {
 101         return new ImmutableMetadataNormalizedNodeStreamWriter(holder);
 102     }
 103
 104     @Override
 105     public void startLeafNode(final NodeIdentifier name) {
 106         checkDataNodeContainer();
 107         enter(name, leafNodeBuilder(nextSchema));
 108         nextSchema = null;
 109     }
 110
 111     @Override
 112     public void startLeafSet(final NodeIdentifier name, final int childSizeHint) {
 113         checkDataNodeContainer();
 114         enter(name, UNKNOWN_SIZE == childSizeHint ? InterningLeafSetNodeBuilder.create(nextSchema)
 115                 : InterningLeafSetNodeBuilder.create(nextSchema, childSizeHint));
 116     }
 117
 118     @Override
 119     public void startLeafSetEntryNode(final NodeWithValue<?> name) {
 120         final var current = current();
 121         checkArgument(current instanceof ImmutableLeafSetNodeBuilder
 122             || current instanceof ImmutableUserLeafSetNodeBuilder || current instanceof NormalizationResultBuilder,
 123             "LeafSetEntryNode is not valid for parent %s", current);
 124         enter(name, leafsetEntryNodeBuilder());
 125         nextSchema = null;
 126     }
 127
 128     @Override
 129     public void startOrderedLeafSet(final NodeIdentifier name, final int childSizeHint) {
 130         checkDataNodeContainer();
 131         enter(name, Builders.orderedLeafSetBuilder());
 132     }
 133
 134     @Override
 135     public boolean startAnyxmlNode(final NodeIdentifier name, final Class<?> objectModel) {
 136         checkDataNodeContainer();
 137         if (DOMSource.class.isAssignableFrom(objectModel)) {
 138             enter(name, Builders.anyXmlBuilder());
 139             nextSchema = null;
 140             return true;
 141         }
 142         return false;
 143     }
 144
 145     @Override
 146     public void startContainerNode(final NodeIdentifier name, final int childSizeHint) {
 147         checkDataNodeContainer();
 148         enter(name, UNKNOWN_SIZE == childSizeHint ? Builders.containerBuilder()
 149             : Builders.containerBuilder(childSizeHint));
 150     }
 151
 152     @Override
 153     public void startUnkeyedList(final NodeIdentifier name, final int childSizeHint) {
 154         checkDataNodeContainer();
 155         enter(name, UNKNOWN_SIZE == childSizeHint ? Builders.unkeyedListBuilder()
 156             : Builders.unkeyedListBuilder(childSizeHint));
 157     }
 158
 159     @Override
 160     public void startUnkeyedListItem(final NodeIdentifier name, final int childSizeHint) {
 161         final var current = current();
 162         checkArgument(current instanceof ImmutableUnkeyedListNodeBuilder
 163             || current instanceof NormalizationResultBuilder);
 164         enter(name, UNKNOWN_SIZE == childSizeHint ? Builders.unkeyedListEntryBuilder()
 165             : Builders.unkeyedListEntryBuilder(childSizeHint));
 166     }
 167
 168     @Override
 169     public void startMapNode(final NodeIdentifier name, final int childSizeHint) {
 170         checkDataNodeContainer();
 171         enter(name, UNKNOWN_SIZE == childSizeHint ? Builders.mapBuilder() : Builders.mapBuilder(childSizeHint));
 172     }
 173
 174     @Override
 175     public void startMapEntryNode(final NodeIdentifierWithPredicates identifier, final int childSizeHint) {
 176         final var current = current();
 177         checkArgument(current instanceof ImmutableMapNodeBuilder || current instanceof ImmutableUserMapNodeBuilder
 178             || current instanceof NormalizationResultBuilder);
 179
 180         enter(identifier, UNKNOWN_SIZE == childSizeHint ? Builders.mapEntryBuilder()
 181             : Builders.mapEntryBuilder(childSizeHint));
 182     }
 183
 184     @Override
 185     public void startOrderedMapNode(final NodeIdentifier name, final int childSizeHint) {
 186         checkDataNodeContainer();
 187         enter(name, UNKNOWN_SIZE == childSizeHint ? Builders.orderedMapBuilder()
 188             : Builders.orderedMapBuilder(childSizeHint));
 189     }
 190
 191     @Override
 192     public void startChoiceNode(final NodeIdentifier name, final int childSizeHint) {
 193         checkDataNodeContainer();
 194         enter(name, UNKNOWN_SIZE == childSizeHint ? Builders.choiceBuilder() : Builders.choiceBuilder(childSizeHint));
 195     }
 196
 197     @Override
 198     public void flush() {
 199         // no-op
 200     }
 201
 202     @Override
 203     public void close() {
 204         // no-op
 205     }
 206
 207     @Override
 208     public void nextDataSchemaNode(final DataSchemaNode schema) {
 209         nextSchema = requireNonNull(schema);
 210     }
 211
 212     @Override
 213     public void scalarValue(final Object value) {
 214         // FIXME: tighten to concrete NormalizedNode.Builder interfaces
 215         currentScalar().withValue(value);
 216     }
 217
 218     @Override
 219     public void domSourceValue(final DOMSource value) {
 220         // FIXME: tighten to concrete NormalizedNode.Builder interfaces
 221         currentScalar().withValue(value);
 222     }
 223
 224     @Override
 225     @SuppressWarnings("rawtypes")
 226     public void endNode() {
 227         final var finishedBuilder = builders.poll();
 228         checkState(finishedBuilder != null, "Node which should be closed does not exists.");
 229         final var product = finishedBuilder.build();
 230         nextSchema = null;
 231
 232         writeChild(product);
 233     }
 234
 235     @Override
 236     public boolean startAnydataNode(final NodeIdentifier name, final Class<?> objectModel) throws IOException {
 237         checkDataNodeContainer();
 238         enter(name, Builders.anydataBuilder(objectModel));
 239         // We support all object models
 240         return true;
 241     }
 242
 243     /**
 244      * Add a child not to the currently-open builder.
 245      *
 246      * @param child A new child
 247      * @throws NullPointerException if {@code child} is null
 248      * @throws IllegalStateException if there is no open builder
 249      */
 250     @SuppressWarnings({ "rawtypes", "unchecked" })
 251     protected final void writeChild(final NormalizedNode child) {
 252         final NormalizedNodeContainerBuilder current = currentContainer();
 253         checkState(current != null, "Reached top level node, which could not be closed in this writer.");
 254         current.addChild(requireNonNull(child));
 255     }
 256
 257     // Exposed for ImmutableMetadataNormalizedNodeStreamWriter
 258     @SuppressWarnings("rawtypes")
 259     void enter(final PathArgument identifier, final NormalizedNodeBuilder next) {
 260         builders.push(next.withNodeIdentifier(identifier));
 261         nextSchema = null;
 262     }
 263
 264     // Exposed for ImmutableMetadataNormalizedNodeStreamWriter
 265     protected final NormalizedNode.Builder popBuilder() {
 266         return builders.pop();
 267     }
 268
 269     final void reset(final NormalizationResultBuilder builder) {
 270         nextSchema = null;
 271         builders.clear();
 272         builders.push(builder);
 273     }
 274
 275     private <T> LeafNode.Builder<T> leafNodeBuilder(final DataSchemaNode schema) {
 276         final var builder = this.<T>leafNodeBuilder();
 277         if (schema instanceof LeafSchemaNode leafSchema) {
 278             final var interner = LeafInterner.<LeafNode<T>>forSchema(leafSchema);
 279             if (interner.isPresent()) {
 280                 return new InterningLeafNodeBuilder<>(builder, interner.orElseThrow());
 281             }
 282         }
 283         return builder;
 284     }
 285
 286     <T> LeafNode.@NonNull Builder<T> leafNodeBuilder() {
 287         return Builders.leafBuilder();
 288     }
 289
 290     <T> LeafSetEntryNode.@NonNull Builder<T> leafsetEntryNodeBuilder() {
 291         return Builders.leafSetEntryBuilder();
 292     }
 293
 294     private void checkDataNodeContainer() {
 295         @SuppressWarnings("rawtypes")
 296         final NormalizedNodeContainerBuilder current = currentContainer();
 297         if (!(current instanceof NormalizationResultBuilder)) {
 298             checkArgument(current instanceof DataContainerNodeBuilder<?, ?>, "Invalid nesting of data.");
 299         }
 300     }
 301
 302     private NormalizedNode.Builder current() {
 303         return builders.peek();
 304     }
 305
 306     @SuppressWarnings("rawtypes")
 307     private NormalizedNodeContainerBuilder currentContainer() {
 308         final var current = current();
 309         if (current instanceof NormalizedNodeContainerBuilder builder) {
 310             return builder;
 311         }
 312         if (current != null) {
 313             throw new IllegalStateException(current + " is not a node container");
 314         }
 315         return null;
 316     }
 317
 318     @SuppressWarnings("rawtypes")
 319     private NormalizedNodeBuilder currentScalar() {
 320         final var current = current();
 321         if (current instanceof NormalizedNodeContainerBuilder) {
 322             throw new IllegalStateException("Unexpected node container " + current);
 323         }
 324         if (current instanceof NormalizedNodeBuilder builder) {
 325             return builder;
 326         }
 327         throw new IllegalStateException("Unexpected non-scalar " + current);
 328     }
 329 }