ONOS-5718 Dynamic Config APIs with RPC and Notification support

Change-Id: I670890efee83c86c7a3b242783c0a62879059849
diff --git a/apps/config/src/main/java/org/onosproject/config/model/DefaultDataNode.java b/apps/config/src/main/java/org/onosproject/config/model/DefaultDataNode.java
new file mode 100755
index 0000000..44b8c1e
--- /dev/null
+++ b/apps/config/src/main/java/org/onosproject/config/model/DefaultDataNode.java
@@ -0,0 +1,163 @@
+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.config.model;
+
+import java.util.LinkedHashMap;
+
+/**
+ * Representation of an instance node in the Dynamic config store.
+ */
+public final class DefaultDataNode implements DataNode {
+    DataNode.Type type;
+    NodeKey key;
+    //Object value;
+    String value;
+    LinkedHashMap<NodeKey, DataNode> children;
+
+    /**
+     * Creates a new DefaultDataNode.
+     *
+     * @param key node key
+     * @param type of the node
+     * @param value of leaf node
+     * @param children of the inner node
+     */
+    private DefaultDataNode(NodeKey key, DataNode.Type type,
+                            String value, LinkedHashMap<NodeKey, DataNode> children) {
+        this.type = type;
+        this.key = key;
+        this.value = value;
+        this.children = children;
+    }
+    /**
+     *
+     */
+    /**
+     * Creates a new DefaultDataNode.
+     *
+     * @param node to be cloned
+     * @param value of leaf node
+     */
+    private DefaultDataNode(DataNode node, String value) {
+        this.type = node.type();
+        this.key = node.key();
+        this.value = value;
+        this.children = null;
+    }
+    /**
+     * Creates a new DefaultDataNode.
+     *
+     * @param node to be cloned
+     * @param children to be added
+     */
+    private DefaultDataNode(DataNode node, LinkedHashMap<NodeKey, DataNode> children) {
+        this.type = node.type();
+        this.key = node.key();
+        this.value = null;
+        this.children = children;
+    }
+
+    @Override
+    public LinkedHashMap<NodeKey, DataNode> children() {
+        return this.children;
+    }
+
+    @Override
+    public  String value() {
+        return value;
+        //return value.toString();
+    }
+
+
+    /**
+     * Creates and returns a new builder instance.
+     *
+     * @return new builder
+     */
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    public static final class Builder<V> implements DataNode.Builder {
+
+        private DataNode.Type type;
+        private NodeKey key;
+        //Object value;
+        private String value;
+        private LinkedHashMap<NodeKey, DataNode> children;
+
+        private Builder() {
+            this.type = null;
+            this.key = null;
+            this.value = null;
+            this.children = null;
+        }
+
+        @Override
+        public Builder addBaseObj(DataNode base) {
+            this.key = base.key();
+            this.type = base.type();
+            this.value = base.value();
+            this.children = base.children();
+            return this;
+        }
+
+        @Override
+        public Builder addKey(NodeKey key) {
+            this.key = key;
+            return this;
+        }
+
+        @Override
+        public Builder addType(DataNode.Type type) {
+            this.type = type;
+            return this;
+        }
+
+        @Override
+        public Builder addValue(String value) {
+            this.value = value;
+            return this;
+        }
+
+        //@Override
+        public Builder addChildren(LinkedHashMap<NodeKey, DataNode> children) {
+            this.children = children;
+            return this;
+        }
+
+        @Override
+        public DataNode build() {
+            return new DefaultDataNode(this.key, this.type, this.value, this.children);
+        }
+    }
+
+
+    @Override
+    public SchemaIdentifier identifier() {
+        return this.key.schemaId;
+    }
+
+    @Override
+    public Type type() {
+        return this.type;
+    }
+
+    @Override
+    public NodeKey key() {
+        return this.key;
+    }
+}
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