Coding gudilines for class and methods javadocs fixed.

Change-Id: I0153e6391c9ec9eacaac65c3989834b6bf5c65bf
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/TreeWalkListener.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/TreeWalkListener.java
index b6ab595..d315d9b 100644
--- a/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/TreeWalkListener.java
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/TreeWalkListener.java
@@ -75,7 +75,7 @@
 import org.onosproject.yangutils.parser.impl.listeners.VersionListener;
 
 /**
- * ANTLR generates a parse-tree listener interface that responds to events
+ * Represents ANTLR generates parse-tree. ANTLR generates a parse-tree listener interface that responds to events
  * triggered by the built-in tree walker. The methods in listener are just
  * callbacks. This class implements listener interface and generates the
  * corresponding data model tree.