YANG Grouping Linker Support

Change-Id: I2fec0c0bb4d1584e82ffba3228106897ccad2bf5
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/datamodel/YangEntityToResolveInfo.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/datamodel/YangEntityToResolveInfo.java
new file mode 100644
index 0000000..7e3d819
--- /dev/null
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/datamodel/YangEntityToResolveInfo.java
@@ -0,0 +1,85 @@
+/*
+ * 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.yangutils.datamodel;
+
+import org.onosproject.yangutils.datamodel.exceptions.DataModelException;
+
+/**
+ * Represents information about entity being resolved.
+ */
+public class YangEntityToResolveInfo<T> {
+
+    // Parsable node for which resolution is to be performed.
+    private T entityToResolve;
+
+    // Holder of the YANG construct for which resolution has to be carried out.
+    private YangNode holderOfEntityToResolve;
+
+    /**
+     * Retrieves the entity to be resolved.
+     *
+     * @return entity to be resolved
+     */
+    public T getEntityToResolve() {
+        return entityToResolve;
+    }
+
+    /**
+     * Sets entity to be resolved.
+     *
+     * @param entityToResolve entity to be resolved
+     */
+    public void setEntityToResolve(T entityToResolve) {
+        this.entityToResolve = entityToResolve;
+    }
+
+    /**
+     * Retrieves the parent node which contains the entity to be resolved.
+     *
+     * @return parent node which contains the entity to be resolved
+     */
+    public YangNode getHolderOfEntityToResolve() {
+        return holderOfEntityToResolve;
+    }
+
+    /**
+     * Sets parent node which contains the entity to be resolved.
+     *
+     * @param holderOfEntityToResolve parent node which contains the entity to be resolved
+     */
+    public void setHolderOfEntityToResolve(YangNode holderOfEntityToResolve) {
+        this.holderOfEntityToResolve = holderOfEntityToResolve;
+    }
+
+
+    public String getEntityPrefix()
+            throws DataModelException {
+        if (getEntityToResolve() == null) {
+            return null;
+        }
+
+        String prefix;
+        T entityToResolve = (T) getEntityToResolve();
+        if (entityToResolve instanceof YangType) {
+            prefix = ((YangType<?>) entityToResolve).getPrefix();
+        } else if (entityToResolve instanceof YangUses) {
+            prefix = ((YangUses) entityToResolve).getPrefix();
+        } else {
+            throw new DataModelException("Data Model Exception: Entity to resolved is other than type/uses");
+        }
+        return prefix;
+    }
+}