yang/yang-data-api/src/main/java/org/opendaylight/yangtools/yang/data/api/schema/tree/DataTreeCandidateNodes.java

   1 /*
   2  * Copyright (c) 2015 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.api.schema.tree;
   9
  10 import com.google.common.annotations.Beta;
  11 import com.google.common.base.Preconditions;
  12 import java.util.Collection;
  13 import java.util.Iterator;
  14 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  15
  16 @Beta
  17 public final class DataTreeCandidateNodes {
  18     private DataTreeCandidateNodes() {
  19         throw new UnsupportedOperationException();
  20     }
  21
  22     public static DataTreeCandidateNode fromNormalizedNode(final NormalizedNode<?, ?> node) {
  23         return new NormalizedNodeDataTreeCandidateNode(node);
  24     }
  25
  26     public static void applyToCursor(final DataTreeModificationCursor cursor, final DataTreeCandidateNode node) {
  27         switch (node.getModificationType()) {
  28         case DELETE:
  29             cursor.delete(node.getIdentifier());
  30             break;
  31         case SUBTREE_MODIFIED:
  32             cursor.enter(node.getIdentifier());
  33             NodeIterator iterator = new NodeIterator(null, node.getChildNodes().iterator());
  34             do {
  35                 iterator = iterator.next(cursor);
  36             } while (iterator != null);
  37             break;
  38         case UNMODIFIED:
  39             // No-op
  40             break;
  41         case WRITE:
  42             cursor.write(node.getIdentifier(), node.getDataAfter().get());
  43             break;
  44         default:
  45             throw new IllegalArgumentException("Unsupported modification " + node.getModificationType());
  46         }
  47     }
  48
  49     private static final class NodeIterator {
  50         private final Iterator<DataTreeCandidateNode> iterator;
  51         private final NodeIterator parent;
  52
  53         NodeIterator(final NodeIterator parent, final Iterator<DataTreeCandidateNode> iterator) {
  54             this.parent = Preconditions.checkNotNull(parent);
  55             this.iterator = Preconditions.checkNotNull(iterator);
  56         }
  57
  58         NodeIterator next(final DataTreeModificationCursor cursor) {
  59             while (iterator.hasNext()) {
  60                 final DataTreeCandidateNode node = iterator.next();
  61                 switch (node.getModificationType()) {
  62                 case DELETE:
  63                     cursor.delete(node.getIdentifier());
  64                     break;
  65                 case SUBTREE_MODIFIED:
  66                     final Collection<DataTreeCandidateNode> children = node.getChildNodes();
  67                     if (!children.isEmpty()) {
  68                         cursor.enter(node.getIdentifier());
  69                         return new NodeIterator(this, children.iterator());
  70                     }
  71                     break;
  72                 case UNMODIFIED:
  73                     // No-op
  74                     break;
  75                 case WRITE:
  76                     cursor.write(node.getIdentifier(), node.getDataAfter().get());
  77                     break;
  78                 default:
  79                     throw new IllegalArgumentException("Unsupported modification " + node.getModificationType());
  80                 }
  81             }
  82
  83             cursor.exit();
  84             return parent;
  85         }
  86     }
  87 }