Improve DtaContainerCodecProtype.loadInstance()

[mdsal.git] / binding / mdsal-binding-dom-codec / src / main / java / org / opendaylight / mdsal / binding / dom / codec / impl / DataContainerCodecPrototype.java

diff --git a/binding/mdsal-binding-dom-codec/src/main/java/org/opendaylight/mdsal/binding/dom/codec/impl/DataContainerCodecPrototype.java b/binding/mdsal-binding-dom-codec/src/main/java/org/opendaylight/mdsal/binding/dom/codec/impl/DataContainerCodecPrototype.java
index f2dd80ebbab75bcfedff1e22a45f4456b0a570ee..2a6abd3d7942472a169cdb8dfbac015303d0f5e2 100644 (file)
--- a/binding/mdsal-binding-dom-codec/src/main/java/org/opendaylight/mdsal/binding/dom/codec/impl/DataContainerCodecPrototype.java
+++ b/binding/mdsal-binding-dom-codec/src/main/java/org/opendaylight/mdsal/binding/dom/codec/impl/DataContainerCodecPrototype.java
@@ -8,7 +8,8 @@
 package org.opendaylight.mdsal.binding.dom.codec.impl;
 
 import com.google.common.collect.Iterables;
-import org.checkerframework.checker.lock.qual.Holding;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.VarHandle;
 import org.eclipse.jdt.annotation.NonNull;
 import org.opendaylight.mdsal.binding.dom.codec.api.BindingDataObjectCodecTreeNode.ChildAddressabilitySummary;
 import org.opendaylight.mdsal.binding.dom.codec.impl.NodeCodecContext.CodecContextFactory;
@@ -20,15 +21,17 @@ import org.opendaylight.yangtools.yang.common.QNameModule;
 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.AugmentationIdentifier;
 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
-import org.opendaylight.yangtools.yang.model.api.AnyDataSchemaNode;
-import org.opendaylight.yangtools.yang.model.api.AnyXmlSchemaNode;
+import org.opendaylight.yangtools.yang.model.api.AnydataSchemaNode;
+import org.opendaylight.yangtools.yang.model.api.AnyxmlSchemaNode;
 import org.opendaylight.yangtools.yang.model.api.AugmentationSchemaNode;
 import org.opendaylight.yangtools.yang.model.api.CaseSchemaNode;
 import org.opendaylight.yangtools.yang.model.api.ChoiceSchemaNode;
+import org.opendaylight.yangtools.yang.model.api.ContainerLike;
 import org.opendaylight.yangtools.yang.model.api.ContainerSchemaNode;
 import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
 import org.opendaylight.yangtools.yang.model.api.DocumentedNode.WithStatus;
+import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
 import org.opendaylight.yangtools.yang.model.api.ListSchemaNode;
 import org.opendaylight.yangtools.yang.model.api.NotificationDefinition;
 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
@@ -39,6 +42,17 @@ import org.slf4j.LoggerFactory;
 final class DataContainerCodecPrototype<T extends WithStatus> implements NodeContextSupplier {
     private static final Logger LOG = LoggerFactory.getLogger(DataContainerCodecPrototype.class);
 
+    private static final VarHandle INSTANCE;
+
+    static {
+        try {
+            INSTANCE = MethodHandles.lookup().findVarHandle(DataContainerCodecPrototype.class,
+                "instance", DataContainerCodecContext.class);
+        } catch (NoSuchFieldException | IllegalAccessException e) {
+            throw new ExceptionInInitializerError(e);
+        }
+    }
+
     private final T schema;
     private final QNameModule namespace;
     private final CodecContextFactory factory;
@@ -46,6 +60,8 @@ final class DataContainerCodecPrototype<T extends WithStatus> implements NodeCon
     private final PathArgument yangArg;
     private final ChildAddressabilitySummary childAddressabilitySummary;
 
+    // Accessed via INSTANCE
+    @SuppressWarnings("unused")
     private volatile DataContainerCodecContext<?, T> instance;
 
     @SuppressWarnings("unchecked")
@@ -84,7 +100,7 @@ final class DataContainerCodecPrototype<T extends WithStatus> implements NodeCon
                     } else {
                         haveAddressable = true;
                     }
-                } else if (child instanceof AnyDataSchemaNode || child instanceof AnyXmlSchemaNode
+                } else if (child instanceof AnydataSchemaNode || child instanceof AnyxmlSchemaNode
                         || child instanceof TypedDataSchemaNode) {
                     haveUnaddressable = true;
                 } else if (child instanceof ChoiceSchemaNode) {
@@ -116,7 +132,7 @@ final class DataContainerCodecPrototype<T extends WithStatus> implements NodeCon
         } else if (nodeSchema instanceof ChoiceSchemaNode) {
             boolean haveAddressable = false;
             boolean haveUnaddressable = false;
-            for (CaseSchemaNode child : ((ChoiceSchemaNode) nodeSchema).getCases().values()) {
+            for (CaseSchemaNode child : ((ChoiceSchemaNode) nodeSchema).getCases()) {
                 switch (computeChildAddressabilitySummary(child)) {
                     case ADDRESSABLE:
                         haveAddressable = true;
@@ -144,28 +160,25 @@ final class DataContainerCodecPrototype<T extends WithStatus> implements NodeCon
         return ChildAddressabilitySummary.UNADDRESSABLE;
     }
 
-    static DataContainerCodecPrototype<SchemaContext> rootPrototype(final CodecContextFactory factory) {
-        final SchemaContext schema = factory.getRuntimeContext().getSchemaContext();
-        final NodeIdentifier arg = NodeIdentifier.create(schema.getQName());
+    static DataContainerCodecPrototype<EffectiveModelContext> rootPrototype(final CodecContextFactory factory) {
+        final EffectiveModelContext schema = factory.getRuntimeContext().getEffectiveModelContext();
+        final NodeIdentifier arg = NodeIdentifier.create(SchemaContext.NAME);
         return new DataContainerCodecPrototype<>(DataRoot.class, arg, schema, factory);
     }
 
-    @SuppressWarnings({ "unchecked", "rawtypes" })
     static <T extends DataSchemaNode> DataContainerCodecPrototype<T> from(final Class<?> cls, final T schema,
             final CodecContextFactory factory) {
-        return new DataContainerCodecPrototype(cls, NodeIdentifier.create(schema.getQName()), schema, factory);
+        return new DataContainerCodecPrototype<>(cls, NodeIdentifier.create(schema.getQName()), schema, factory);
     }
 
-    @SuppressWarnings({ "unchecked", "rawtypes" })
     static <T extends DataSchemaNode> DataContainerCodecPrototype<T> from(final Item<?> bindingArg, final T schema,
             final CodecContextFactory factory) {
-        return new DataContainerCodecPrototype(bindingArg, NodeIdentifier.create(schema.getQName()), schema, factory);
+        return new DataContainerCodecPrototype<>(bindingArg, NodeIdentifier.create(schema.getQName()), schema, factory);
     }
 
-    @SuppressWarnings({ "rawtypes", "unchecked" })
-    static DataContainerCodecPrototype<?> from(final Class<?> augClass, final AugmentationIdentifier arg,
-            final AugmentationSchemaNode schema, final CodecContextFactory factory) {
-        return new DataContainerCodecPrototype(augClass, arg, schema, factory);
+    static DataContainerCodecPrototype<AugmentationSchemaNode> from(final Class<?> augClass,
+            final AugmentationIdentifier arg, final AugmentationSchemaNode schema, final CodecContextFactory factory) {
+        return new DataContainerCodecPrototype<>(augClass, arg, schema, factory);
     }
 
     static DataContainerCodecPrototype<NotificationDefinition> from(final Class<?> augClass,
@@ -174,7 +187,7 @@ final class DataContainerCodecPrototype<T extends WithStatus> implements NodeCon
         return new DataContainerCodecPrototype<>(augClass,arg, schema, factory);
     }
 
-    protected T getSchema() {
+    T getSchema() {
         return schema;
     }
 
@@ -182,50 +195,48 @@ final class DataContainerCodecPrototype<T extends WithStatus> implements NodeCon
         return childAddressabilitySummary;
     }
 
-    protected QNameModule getNamespace() {
+    QNameModule getNamespace() {
         return namespace;
     }
 
-    protected CodecContextFactory getFactory() {
+    CodecContextFactory getFactory() {
         return factory;
     }
 
-    protected Class<?> getBindingClass() {
+    Class<?> getBindingClass() {
         return bindingArg.getType();
     }
 
-    protected Item<?> getBindingArg() {
+    Item<?> getBindingArg() {
         return bindingArg;
     }
 
-    protected PathArgument getYangArg() {
+    PathArgument getYangArg() {
         return yangArg;
     }
 
     @Override
     public DataContainerCodecContext<?, T> get() {
-        DataContainerCodecContext<?, T> tmp = instance;
-        if (tmp == null) {
-            synchronized (this) {
-                tmp = instance;
-                if (tmp == null) {
-                    instance = tmp = createInstance();
-                }
-            }
-        }
+        final DataContainerCodecContext<?, T> existing = (DataContainerCodecContext<?, T>) INSTANCE.getAcquire(this);
+        return existing != null ? existing : loadInstance();
+    }
 
-        return tmp;
+    private @NonNull DataContainerCodecContext<?, T> loadInstance() {
+        final var tmp = createInstance();
+        final var witness = (DataContainerCodecContext<?, T>) INSTANCE.compareAndExchangeRelease(this, null, tmp);
+        return witness == null ? tmp : witness;
     }
 
-    @Holding("this")
     @SuppressWarnings({ "rawtypes", "unchecked" })
+    // This method must allow concurrent loading, i.e. nothing in it may have effects outside of the loaded object
     private @NonNull DataContainerCodecContext<?, T> createInstance() {
         // FIXME: make protected abstract
-        if (schema instanceof ContainerSchemaNode) {
+        if (schema instanceof ContainerLike) {
             return new ContainerNodeCodecContext(this);
         } else if (schema instanceof ListSchemaNode) {
-            return Identifiable.class.isAssignableFrom(getBindingClass()) ? new KeyedListNodeCodecContext(this)
-                    : new ListNodeCodecContext(this);
+            return Identifiable.class.isAssignableFrom(getBindingClass())
+                    ? KeyedListNodeCodecContext.create((DataContainerCodecPrototype<ListSchemaNode>) this)
+                            : new ListNodeCodecContext(this);
         } else if (schema instanceof ChoiceSchemaNode) {
             return new ChoiceNodeCodecContext(this);
         } else if (schema instanceof AugmentationSchemaNode) {
@@ -236,6 +247,7 @@ final class DataContainerCodecPrototype<T extends WithStatus> implements NodeCon
         throw new IllegalArgumentException("Unsupported type " + getBindingClass() + " " + schema);
     }
 
+    // FIXME: eliminate with above createInstance() item
     boolean isChoice() {
         return schema instanceof ChoiceSchemaNode;
     }