opendaylight/md-sal/sal-dom-broker/src/main/java/org/opendaylight/controller/md/sal/dom/store/impl/DataChangeEventResolver.java

   1 package org.opendaylight.controller.md.sal.dom.store.impl;
   2
   3 import static org.opendaylight.controller.md.sal.dom.store.impl.DOMImmutableDataChangeEvent.builder;
   4 import static org.opendaylight.controller.md.sal.dom.store.impl.StoreUtils.append;
   5 import static org.opendaylight.controller.md.sal.dom.store.impl.tree.TreeNodeUtils.getChild;
   6
   7 import java.util.Collection;
   8 import java.util.HashSet;
   9 import java.util.Set;
  10
  11 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker.DataChangeScope;
  12 import org.opendaylight.controller.md.sal.dom.store.impl.DOMImmutableDataChangeEvent.Builder;
  13 import org.opendaylight.controller.md.sal.dom.store.impl.tree.ListenerTree;
  14 import org.opendaylight.controller.md.sal.dom.store.impl.tree.ListenerTree.Walker;
  15 import org.opendaylight.controller.md.sal.dom.store.impl.tree.NodeModification;
  16 import org.opendaylight.controller.md.sal.dom.store.impl.tree.StoreMetadataNode;
  17 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
  18 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.PathArgument;
  19 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  20 import org.slf4j.Logger;
  21 import org.slf4j.LoggerFactory;
  22
  23 import com.google.common.base.Optional;
  24 import com.google.common.collect.ImmutableList;
  25 import com.google.common.collect.ImmutableSet;
  26
  27 public class DataChangeEventResolver {
  28     private static final Logger LOG = LoggerFactory.getLogger(DataChangeEventResolver.class);
  29     private static final DOMImmutableDataChangeEvent NO_CHANGE = builder().build();
  30     private final ImmutableList.Builder<ChangeListenerNotifyTask> tasks = ImmutableList.builder();
  31     private InstanceIdentifier rootPath;
  32     private ListenerTree listenerRoot;
  33     private NodeModification modificationRoot;
  34     private Optional<StoreMetadataNode> beforeRoot;
  35     private Optional<StoreMetadataNode> afterRoot;
  36
  37     protected InstanceIdentifier getRootPath() {
  38         return rootPath;
  39     }
  40
  41     protected DataChangeEventResolver setRootPath(final InstanceIdentifier rootPath) {
  42         this.rootPath = rootPath;
  43         return this;
  44     }
  45
  46     protected ListenerTree getListenerRoot() {
  47         return listenerRoot;
  48     }
  49
  50     protected DataChangeEventResolver setListenerRoot(final ListenerTree listenerRoot) {
  51         this.listenerRoot = listenerRoot;
  52         return this;
  53     }
  54
  55     protected NodeModification getModificationRoot() {
  56         return modificationRoot;
  57     }
  58
  59     protected DataChangeEventResolver setModificationRoot(final NodeModification modificationRoot) {
  60         this.modificationRoot = modificationRoot;
  61         return this;
  62     }
  63
  64     protected Optional<StoreMetadataNode> getBeforeRoot() {
  65         return beforeRoot;
  66     }
  67
  68     protected DataChangeEventResolver setBeforeRoot(final Optional<StoreMetadataNode> beforeRoot) {
  69         this.beforeRoot = beforeRoot;
  70         return this;
  71     }
  72
  73     protected Optional<StoreMetadataNode> getAfterRoot() {
  74         return afterRoot;
  75     }
  76
  77     protected DataChangeEventResolver setAfterRoot(final Optional<StoreMetadataNode> afterRoot) {
  78         this.afterRoot = afterRoot;
  79         return this;
  80     }
  81
  82     public Iterable<ChangeListenerNotifyTask> resolve() {
  83         LOG.trace("Resolving events for {}", modificationRoot);
  84
  85         try (final Walker w = listenerRoot.getWalker()) {
  86             resolveAnyChangeEvent(rootPath, Optional.of(w.getRootNode()), modificationRoot, beforeRoot, afterRoot);
  87             return tasks.build();
  88         }
  89     }
  90
  91     private DOMImmutableDataChangeEvent resolveAnyChangeEvent(final InstanceIdentifier path,
  92             final Optional<ListenerTree.Node> listeners, final NodeModification modification,
  93             final Optional<StoreMetadataNode> before, final Optional<StoreMetadataNode> after) {
  94         // No listeners are present in listener registration subtree
  95         // no before and after state is present
  96         if (!before.isPresent() && !after.isPresent()) {
  97             return NO_CHANGE;
  98         }
  99         switch (modification.getModificationType()) {
 100         case SUBTREE_MODIFIED:
 101             return resolveSubtreeChangeEvent(path, listeners, modification, before.get(), after.get());
 102         case WRITE:
 103             if (before.isPresent()) {
 104                 return resolveReplacedEvent(path, listeners, modification, before.get(), after.get());
 105             } else {
 106                 return resolveCreateEvent(path, listeners, after.get());
 107             }
 108         case DELETE:
 109             return resolveDeleteEvent(path, listeners, before.get());
 110         default:
 111             return NO_CHANGE;
 112         }
 113
 114     }
 115
 116     /**
 117      * Resolves create events deep down the interest listener tree.
 118      *
 119      *
 120      * @param path
 121      * @param listeners
 122      * @param afterState
 123      * @return
 124      */
 125     private DOMImmutableDataChangeEvent resolveCreateEvent(final InstanceIdentifier path,
 126             final Optional<ListenerTree.Node> listeners, final StoreMetadataNode afterState) {
 127         final NormalizedNode<?, ?> node = afterState.getData();
 128         Builder builder = builder().setAfter(node).addCreated(path, node);
 129
 130         for (StoreMetadataNode child : afterState.getChildren()) {
 131             PathArgument childId = child.getIdentifier();
 132             Optional<ListenerTree.Node> childListeners = getChild(listeners, childId);
 133
 134             InstanceIdentifier childPath = StoreUtils.append(path, childId);
 135             builder.merge(resolveCreateEvent(childPath, childListeners, child));
 136         }
 137
 138         return addNotifyTask(listeners, builder.build());
 139     }
 140
 141     private DOMImmutableDataChangeEvent resolveDeleteEvent(final InstanceIdentifier path,
 142             final Optional<ListenerTree.Node> listeners, final StoreMetadataNode beforeState) {
 143         final NormalizedNode<?, ?> node = beforeState.getData();
 144         Builder builder = builder().setBefore(node).addRemoved(path, node);
 145
 146         for (StoreMetadataNode child : beforeState.getChildren()) {
 147             PathArgument childId = child.getIdentifier();
 148             Optional<ListenerTree.Node> childListeners = getChild(listeners, childId);
 149             InstanceIdentifier childPath = StoreUtils.append(path, childId);
 150             builder.merge(resolveDeleteEvent(childPath, childListeners, child));
 151         }
 152         return addNotifyTask(listeners, builder.build());
 153     }
 154
 155     private DOMImmutableDataChangeEvent resolveSubtreeChangeEvent(final InstanceIdentifier path,
 156             final Optional<ListenerTree.Node> listeners, final NodeModification modification,
 157             final StoreMetadataNode before, final StoreMetadataNode after) {
 158
 159         Builder one = builder().setBefore(before.getData()).setAfter(after.getData());
 160
 161         Builder subtree = builder();
 162
 163         for (NodeModification childMod : modification.getModifications()) {
 164             PathArgument childId = childMod.getIdentifier();
 165             InstanceIdentifier childPath = append(path, childId);
 166             Optional<ListenerTree.Node> childListen = getChild(listeners, childId);
 167
 168             Optional<StoreMetadataNode> childBefore = before.getChild(childId);
 169             Optional<StoreMetadataNode> childAfter = after.getChild(childId);
 170
 171             switch (childMod.getModificationType()) {
 172             case WRITE:
 173             case DELETE:
 174                 one.merge(resolveAnyChangeEvent(childPath, childListen, childMod, childBefore, childAfter));
 175                 break;
 176             case SUBTREE_MODIFIED:
 177                 subtree.merge(resolveSubtreeChangeEvent(childPath, childListen, childMod, childBefore.get(),
 178                         childAfter.get()));
 179                 break;
 180             case UNMODIFIED:
 181                 // no-op
 182                 break;
 183             }
 184         }
 185         DOMImmutableDataChangeEvent oneChangeEvent = one.build();
 186         subtree.merge(oneChangeEvent);
 187         DOMImmutableDataChangeEvent subtreeEvent = subtree.build();
 188         if (listeners.isPresent()) {
 189             addNotifyTask(listeners.get(), DataChangeScope.ONE, oneChangeEvent);
 190             addNotifyTask(listeners.get(), DataChangeScope.SUBTREE, subtreeEvent);
 191         }
 192         return subtreeEvent;
 193     }
 194
 195     private DOMImmutableDataChangeEvent resolveReplacedEvent(final InstanceIdentifier path,
 196             final Optional<ListenerTree.Node> listeners, final NodeModification modification,
 197             final StoreMetadataNode before, final StoreMetadataNode after) {
 198         // FIXME Add task
 199         return builder().build();
 200     }
 201
 202     private DOMImmutableDataChangeEvent addNotifyTask(final Optional<ListenerTree.Node> listeners, final DOMImmutableDataChangeEvent event) {
 203         if (listeners.isPresent()) {
 204             final Collection<DataChangeListenerRegistration<?>> l = listeners.get().getListeners();
 205             if (!l.isEmpty()) {
 206                 tasks.add(new ChangeListenerNotifyTask(ImmutableSet.copyOf(l), event));
 207             }
 208         }
 209
 210         return event;
 211     }
 212
 213     private void addNotifyTask(final ListenerTree.Node listenerRegistrationNode, final DataChangeScope scope,
 214             final DOMImmutableDataChangeEvent event) {
 215         Collection<DataChangeListenerRegistration<?>> potential = listenerRegistrationNode.getListeners();
 216         if(!potential.isEmpty()) {
 217             final Set<DataChangeListenerRegistration<?>> toNotify = new HashSet<>(potential.size());
 218             for(DataChangeListenerRegistration<?> listener : potential) {
 219                 if(scope.equals(listener.getScope())) {
 220                     toNotify.add(listener);
 221                 }
 222             }
 223
 224             if (!toNotify.isEmpty()) {
 225                 tasks.add(new ChangeListenerNotifyTask(toNotify, event));
 226             }
 227         }
 228     }
 229
 230     public static DataChangeEventResolver create() {
 231         return new DataChangeEventResolver();
 232     }
 233 }