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