YANG construct collision detection framework added

Change-Id: I1458f9e3192641f3f90c444798c31a64536ffa5d
diff --git a/src/main/java/org/onosproject/yangutils/parser/impl/listeners/MandatoryListener.java b/src/main/java/org/onosproject/yangutils/parser/impl/listeners/MandatoryListener.java
index 2e118ce..ea33cd7 100644
--- a/src/main/java/org/onosproject/yangutils/parser/impl/listeners/MandatoryListener.java
+++ b/src/main/java/org/onosproject/yangutils/parser/impl/listeners/MandatoryListener.java
@@ -22,7 +22,7 @@
 import org.onosproject.yangutils.parser.exceptions.ParserException;
 import org.onosproject.yangutils.parser.impl.TreeWalkListener;
 
-import static org.onosproject.yangutils.parser.ParsableDataType.MANDATORY_DATA;
+import static org.onosproject.yangutils.utils.YangConstructType.MANDATORY_DATA;
 import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorLocation.ENTRY;
 import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorMessageConstruction.constructListenerErrorMessage;
 import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorType.INVALID_HOLDER;
@@ -62,8 +62,8 @@
      * rule (mandatory), performs validation and updates the data model
      * tree.
      *
-     * @param listener listener's object.
-     * @param ctx context object of the grammar rule.
+     * @param listener listener's object
+     * @param ctx context object of the grammar rule
      */
     public static void processMandatoryEntry(TreeWalkListener listener,
                                           GeneratedYangParser.MandatoryStatementContext ctx) {
@@ -72,7 +72,7 @@
         checkStackIsNotEmpty(listener, MISSING_HOLDER, MANDATORY_DATA, "", ENTRY);
 
         Parsable tmpNode = listener.getParsedDataStack().peek();
-        switch (tmpNode.getParsableDataType()) {
+        switch (tmpNode.getYangConstructType()) {
             case LEAF_DATA:
                 YangLeaf leaf = (YangLeaf) tmpNode;
                 if (ctx.TRUE_KEYWORD() != null) {