data/yang-data-impl/src/main/java/org/opendaylight/yangtools/yang/data/impl/schema/ImmutableMetadataNormalizedNodeStreamWriter.java

   1 /*
   2  * Copyright (c) 2019 PANTHEON.tech, s.r.o. 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.checkState;
  11 import static java.util.Objects.requireNonNull;
  12
  13 import com.google.common.annotations.Beta;
  14 import com.google.common.collect.ClassToInstanceMap;
  15 import com.google.common.collect.ImmutableClassToInstanceMap;
  16 import com.google.common.collect.ImmutableMap;
  17 import java.io.IOException;
  18 import java.util.ArrayDeque;
  19 import java.util.Deque;
  20 import org.eclipse.jdt.annotation.NonNull;
  21 import org.opendaylight.yangtools.rfc7952.data.api.NormalizedMetadata;
  22 import org.opendaylight.yangtools.rfc7952.data.api.StreamWriterMetadataExtension;
  23 import org.opendaylight.yangtools.rfc7952.data.util.ImmutableNormalizedMetadata;
  24 import org.opendaylight.yangtools.rfc7952.data.util.ImmutableNormalizedMetadata.Builder;
  25 import org.opendaylight.yangtools.yang.common.QName;
  26 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  27 import org.opendaylight.yangtools.yang.data.api.schema.builder.NormalizedNodeBuilder;
  28 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriterExtension;
  29
  30 /**
  31  * A {@link NormalizedMetadata}-aware {@link ImmutableMetadataNormalizedNodeStreamWriter}. It advertizes the
  32  * {@link StreamWriterMetadataExtension} extension.
  33  */
  34 @Beta
  35 public class ImmutableMetadataNormalizedNodeStreamWriter extends ImmutableNormalizedNodeStreamWriter
  36         implements StreamWriterMetadataExtension {
  37     /**
  38      * Snapshot of currently-open data- and metadatastate.
  39      */
  40     public static final class State {
  41         final Builder metaBuilder;
  42         final NormalizedNodeBuilder dataBuilder;
  43
  44         State(final NormalizedNodeBuilder dataBuilder, final Builder metadataBuilder) {
  45             this.dataBuilder = requireNonNull(dataBuilder);
  46             this.metaBuilder = requireNonNull(metadataBuilder);
  47         }
  48
  49         public NormalizedNodeBuilder getDataBuilder() {
  50             return dataBuilder;
  51         }
  52
  53         public Builder getMetaBuilder() {
  54             return metaBuilder;
  55         }
  56     }
  57
  58     private final Deque<Builder> builders = new ArrayDeque<>();
  59     private final NormalizedNodeMetadataResult result;
  60
  61     protected ImmutableMetadataNormalizedNodeStreamWriter(final State state) {
  62         super(state.getDataBuilder());
  63         builders.push(state.getMetaBuilder());
  64         result = null;
  65     }
  66
  67     protected ImmutableMetadataNormalizedNodeStreamWriter(final NormalizedNodeMetadataResult result) {
  68         super(result);
  69         this.result = requireNonNull(result);
  70     }
  71
  72     @Override
  73     public final ClassToInstanceMap<NormalizedNodeStreamWriterExtension> getExtensions() {
  74         return ImmutableClassToInstanceMap.of(StreamWriterMetadataExtension.class, this);
  75     }
  76
  77     @Override
  78     public final void metadata(final ImmutableMap<QName, Object> metadata) throws IOException {
  79         final Builder current = builders.peek();
  80         checkState(current != null, "Attempted to emit metadata when no metadata is open");
  81         current.withAnnotations(metadata);
  82     }
  83
  84     /**
  85      * Remove the currently-open builders for data and metadata from the stack.
  86      *
  87      * @return Builder state.
  88      */
  89     protected final @NonNull State popState() {
  90         return new State(popBuilder(), builders.pop());
  91     }
  92
  93     @Override
  94     @SuppressWarnings("rawtypes")
  95     final void enter(final PathArgument identifier, final NormalizedNodeBuilder next) {
  96         super.enter(identifier, next);
  97         builders.push(ImmutableNormalizedMetadata.builder().withIdentifier(identifier));
  98     }
  99
 100     @Override
 101     public final void endNode() {
 102         super.endNode();
 103         final ImmutableNormalizedMetadata metadata = builders.pop().build();
 104         final Builder current = builders.peek();
 105         if (current != null) {
 106             if (!metadata.getAnnotations().isEmpty() || !metadata.getChildren().isEmpty()) {
 107                 current.withChild(metadata);
 108             }
 109         } else {
 110             // All done
 111             result.setResult(metadata);
 112         }
 113     }
 114 }