Merge changes I057476f2,I5b8602e7
[controller.git] / opendaylight / md-sal / sal-dom-broker / src / main / java / org / opendaylight / controller / md / sal / dom / store / impl / tree / data / InMemoryDataTreeModification.java
index fcb3ae0a10cf9028193dcdb60cea8a3a432664b3..39ff4f0aa03f9b0ad1d3ccdce080b4cf7c7989a2 100644 (file)
@@ -7,13 +7,12 @@
  */
 package org.opendaylight.controller.md.sal.dom.store.impl.tree.data;
 
-import static com.google.common.base.Preconditions.checkState;
-
 import java.util.Map.Entry;
-import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
+
+import javax.annotation.concurrent.GuardedBy;
 
 import org.opendaylight.controller.md.sal.dom.store.impl.tree.DataTreeModification;
-import org.opendaylight.controller.md.sal.dom.store.impl.tree.StoreUtils;
+import org.opendaylight.controller.md.sal.dom.store.impl.tree.ModificationType;
 import org.opendaylight.controller.md.sal.dom.store.impl.tree.TreeNodeUtils;
 import org.opendaylight.controller.md.sal.dom.store.impl.tree.spi.TreeNode;
 import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier;
@@ -29,19 +28,13 @@ import com.google.common.base.Preconditions;
 
 final class InMemoryDataTreeModification implements DataTreeModification {
     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDataTreeModification.class);
-
-    /*
-     * FIXME: the thread safety of concurrent write/delete/read/seal operations
-     *        needs to be evaluated.
-     */
-    private static final AtomicIntegerFieldUpdater<InMemoryDataTreeModification> SEALED_UPDATER =
-            AtomicIntegerFieldUpdater.newUpdater(InMemoryDataTreeModification.class, "sealed");
-    private volatile int sealed = 0;
-
     private final ModificationApplyOperation strategyTree;
     private final InMemoryDataTreeSnapshot snapshot;
     private final ModifiedNode rootNode;
 
+    @GuardedBy("this")
+    private boolean sealed = false;
+
     InMemoryDataTreeModification(final InMemoryDataTreeSnapshot snapshot, final ModificationApplyOperation resolver) {
         this.snapshot = Preconditions.checkNotNull(snapshot);
         this.strategyTree = Preconditions.checkNotNull(resolver);
@@ -57,13 +50,13 @@ final class InMemoryDataTreeModification implements DataTreeModification {
     }
 
     @Override
-    public void write(final InstanceIdentifier path, final NormalizedNode<?, ?> value) {
+    public synchronized void write(final InstanceIdentifier path, final NormalizedNode<?, ?> value) {
         checkSealed();
         resolveModificationFor(path).write(value);
     }
 
     @Override
-    public void merge(final InstanceIdentifier path, final NormalizedNode<?, ?> data) {
+    public synchronized void merge(final InstanceIdentifier path, final NormalizedNode<?, ?> data) {
         checkSealed();
         mergeImpl(resolveModificationFor(path),data);
     }
@@ -82,13 +75,13 @@ final class InMemoryDataTreeModification implements DataTreeModification {
     }
 
     @Override
-    public void delete(final InstanceIdentifier path) {
+    public synchronized void delete(final InstanceIdentifier path) {
         checkSealed();
         resolveModificationFor(path).delete();
     }
 
     @Override
-    public Optional<NormalizedNode<?, ?>> readNode(final InstanceIdentifier path) {
+    public synchronized Optional<NormalizedNode<?, ?>> readNode(final InstanceIdentifier path) {
         /*
          * Walk the tree from the top, looking for the first node between root and
          * the requested path which has been modified. If no such node exists,
@@ -116,7 +109,7 @@ final class InMemoryDataTreeModification implements DataTreeModification {
 
         try {
             return resolveModificationStrategy(path).apply(modification, modification.getOriginal(),
-                    StoreUtils.increase(snapshot.getRootNode().getSubtreeVersion()));
+                    snapshot.getRootNode().getSubtreeVersion().next());
         } catch (Exception e) {
             LOG.error("Could not create snapshot for {}:{}", path,modification,e);
             throw e;
@@ -139,14 +132,15 @@ final class InMemoryDataTreeModification implements DataTreeModification {
     }
 
     @Override
-    public void seal() {
-        final boolean success = SEALED_UPDATER.compareAndSet(this, 0, 1);
-        Preconditions.checkState(success, "Attempted to seal an already-sealed Data Tree.");
+    public synchronized void ready() {
+        Preconditions.checkState(!sealed, "Attempted to seal an already-sealed Data Tree.");
+        sealed = true;
         rootNode.seal();
     }
 
+    @GuardedBy("this")
     private void checkSealed() {
-        checkState(sealed == 0, "Data Tree is sealed. No further modifications allowed.");
+        Preconditions.checkState(!sealed, "Data Tree is sealed. No further modifications allowed.");
     }
 
     @Override
@@ -155,8 +149,30 @@ final class InMemoryDataTreeModification implements DataTreeModification {
     }
 
     @Override
-    public DataTreeModification newModification() {
-        // FIXME: transaction chaining
-        throw new UnsupportedOperationException("Implement this as part of transaction chaining");
+    public synchronized DataTreeModification newModification() {
+        Preconditions.checkState(sealed, "Attempted to chain on an unsealed modification");
+
+        if(rootNode.getType() == ModificationType.UNMODIFIED) {
+            return snapshot.newModification();
+        }
+
+        /*
+         *  FIXME: Add advanced transaction chaining for modification of not rebased
+         *  modification.
+         *
+         *  Current computation of tempRoot may yeld incorrect subtree versions
+         *  if there are multiple concurrent transactions, which may break
+         *  versioning preconditions for modification of previously occured write,
+         *  directly nested under parent node, since node version is derived from
+         *  subtree version.
+         *
+         *  For deeper nodes subtree version is derived from their respective metadata
+         *  nodes, so this incorrect root subtree version is not affecting us.
+         */
+        TreeNode originalSnapshotRoot = snapshot.getRootNode();
+        Optional<TreeNode> tempRoot = strategyTree.apply(rootNode, Optional.of(originalSnapshotRoot), originalSnapshotRoot.getSubtreeVersion().next());
+
+        InMemoryDataTreeSnapshot tempTree = new InMemoryDataTreeSnapshot(snapshot.getSchemaContext(), tempRoot.get(), strategyTree);
+        return tempTree.newModification();
     }
 }