Whitebox issue fix

Change-Id: I856266e26d2686affb9271c460927ba3e0e07db2
diff --git a/src/main/java/org/onosproject/yangutils/parser/impl/YangUtilsParserManager.java b/src/main/java/org/onosproject/yangutils/parser/impl/YangUtilsParserManager.java
index a1fffb8..6a5b1d2 100644
--- a/src/main/java/org/onosproject/yangutils/parser/impl/YangUtilsParserManager.java
+++ b/src/main/java/org/onosproject/yangutils/parser/impl/YangUtilsParserManager.java
@@ -43,12 +43,11 @@
          * Create a char stream that reads from YANG file. Throws an exception
          * in case input YANG file is either null or non existent.
          */
-        ANTLRInputStream input = null;
+        ANTLRInputStream input;
         try {
             input = new ANTLRFileStream(yangFile);
         } catch (IOException e) {
-            e.printStackTrace();
-            throw e;
+            throw new ParserException("YANG file error : YANG file does not exist.");
         }
 
         // Create a lexer that feeds off of input char stream.