Coding gudilines for class and methods javadocs fixed.

Change-Id: I0153e6391c9ec9eacaac65c3989834b6bf5c65bf
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 610cb66..1363091 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
@@ -22,13 +22,13 @@
 import org.onosproject.yangutils.parser.exceptions.ParserException;
 import org.onosproject.yangutils.parser.impl.TreeWalkListener;
 
-import static org.onosproject.yangutils.parser.impl.parserutils.ListenerUtil.getValidBooleanValue;
-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;
 import static org.onosproject.yangutils.parser.impl.parserutils.ListenerErrorType.MISSING_HOLDER;
+import static org.onosproject.yangutils.parser.impl.parserutils.ListenerUtil.getValidBooleanValue;
 import static org.onosproject.yangutils.parser.impl.parserutils.ListenerValidation.checkStackIsNotEmpty;
+import static org.onosproject.yangutils.utils.YangConstructType.MANDATORY_DATA;
 
 /*
  * Reference: RFC6020 and YANG ANTLR Grammar
@@ -48,7 +48,7 @@
  */
 
 /**
- * Implements listener based call back function corresponding to the "mandatory"
+ * Represents listener based call back function corresponding to the "mandatory"
  * rule defined in ANTLR grammar file for corresponding ABNF rule in RFC 6020.
  */
 public final class MandatoryListener {