Add NormalizedNodeContainer.size()

[yangtools.git] / yang / yang-data-api / src / main / java / org / opendaylight / yangtools / yang / data / api / schema / NormalizedNodeContainer.java

diff --git a/yang/yang-data-api/src/main/java/org/opendaylight/yangtools/yang/data/api/schema/NormalizedNodeContainer.java b/yang/yang-data-api/src/main/java/org/opendaylight/yangtools/yang/data/api/schema/NormalizedNodeContainer.java
index 48d0b6eeb62c38a6b9cc4d0299ac959a3837e70a..536b15883060562f80c01e49d367c501cc2f36b8 100644 (file)
--- a/yang/yang-data-api/src/main/java/org/opendaylight/yangtools/yang/data/api/schema/NormalizedNodeContainer.java
+++ b/yang/yang-data-api/src/main/java/org/opendaylight/yangtools/yang/data/api/schema/NormalizedNodeContainer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
+ * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
@@ -7,30 +7,56 @@
  */
 package org.opendaylight.yangtools.yang.data.api.schema;
 
-import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.PathArgument;
-
-import com.google.common.base.Optional;
+import java.util.Collection;
+import java.util.Optional;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
 
 /**
+ * Node which is not leaf, but has child {@link NormalizedNode}s as its value.
+ *
+ * <p>
+ * NormalizedNodeContainer does not have a value, but it has a child nodes. Definition of possible and valid child nodes
+ * is introduced in subclasses of this interface.
+ *
+ * <p>
+ * This interface should not be used directly, but rather use of of derived subclasses such as
+ * {@link DataContainerNode}, {@link MapNode}, {@link LeafSetNode}.
  *
  * @param <I> Node Identifier type
  * @param <K> Child Node Identifier type
  * @param <V> Child Node type
  */
-public interface NormalizedNodeContainer<I extends PathArgument, K extends PathArgument, V extends NormalizedNode<? extends K, ?>>
-        extends NormalizedNode<I, Iterable<V>> {
+public interface NormalizedNodeContainer<I extends PathArgument, K extends PathArgument,
+       V extends NormalizedNode<? extends K, ?>> extends NormalizedNode<I, Collection<V>> {
 
     @Override
     I getIdentifier();
 
+    /**
+     * Returns immutable iteration of child nodes of this node.
+     */
     @Override
-    Iterable<V> getValue();
+    Collection<V> getValue();
 
     /**
+     * Return the logical size of this container, i.e. the number of children in contains.
      *
+     * <p>
+     * Default implementation defers to the collection returned by {@link #getValue()}. Implementations are strongly
+     * encouraged to provide a more efficient implementation of this method.
+     *
+     * @return Number of child nodes in this container.
+     */
+    // FIXME: 6.0.0: consider making this method non-default
+    default int size() {
+        return getValue().size();
+    }
+
+    /**
+     * Returns child node identified by provided key.
      *
-     * @param child
-     * @return
+     * @param child Path argument identifying child node
+     * @return Optional with child node if child exists. {@link Optional#empty()} if child does not exist.
      */
     Optional<V> getChild(K child);
 }