[ONOS-4527,ONOS-4524,ONOS-4536,ONOS-4541,ONOS-4549,ONOS-4550,ONOS-4557
,ONOS-4558,ONOS-4545,ONOS-4543,ONOS-4546]
 Checkstyle error in generated code handled and defect fixed.

Change-Id: Ifef5a22f91d4ee21767f1e2c6d0dd5b5b0b8cfcc
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/tojava/javamodel/YangJavaSubModule.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/tojava/javamodel/YangJavaSubModule.java
index 59d4912..8696495 100644
--- a/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/tojava/javamodel/YangJavaSubModule.java
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/translator/tojava/javamodel/YangJavaSubModule.java
@@ -16,8 +16,13 @@
 package org.onosproject.yangutils.translator.tojava.javamodel;
 
 import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
 import org.onosproject.yangutils.datamodel.YangBelongsTo;
 import org.onosproject.yangutils.datamodel.YangModule;
+import org.onosproject.yangutils.datamodel.YangNode;
+import org.onosproject.yangutils.datamodel.YangNotification;
 import org.onosproject.yangutils.datamodel.YangSubModule;
 import org.onosproject.yangutils.translator.exception.TranslatorException;
 import org.onosproject.yangutils.translator.tojava.JavaCodeGenerator;
@@ -25,6 +30,9 @@
 import org.onosproject.yangutils.translator.tojava.TempJavaCodeFragmentFiles;
 import org.onosproject.yangutils.translator.tojava.utils.YangPluginConfig;
 
+import static org.onosproject.yangutils.translator.tojava.GeneratedJavaFileType.GENERATE_EVENT_CLASS;
+import static org.onosproject.yangutils.translator.tojava.GeneratedJavaFileType.GENERATE_EVENT_LISTENER_INTERFACE;
+import static org.onosproject.yangutils.translator.tojava.GeneratedJavaFileType.GENERATE_EVENT_SUBJECT_CLASS;
 import static org.onosproject.yangutils.translator.tojava.GeneratedJavaFileType.GENERATE_SERVICE_AND_MANAGER;
 import static org.onosproject.yangutils.translator.tojava.utils.JavaIdentifierSyntax.getRootPackage;
 import static org.onosproject.yangutils.translator.tojava.utils.YangJavaModelUtils.generateCodeOfRootNode;
@@ -49,12 +57,22 @@
     private TempJavaCodeFragmentFiles tempFileHandle;
 
     /**
+     * List of notifications nodes.
+     */
+    private List<YangNode> notificationNodes = new ArrayList<>();
+
+    /**
      * Creates YANG java sub module object.
      */
     public YangJavaSubModule() {
         super();
         setJavaFileInfo(new JavaFileInfo());
-        getJavaFileInfo().setGeneratedFileTypes(GENERATE_SERVICE_AND_MANAGER);
+        int gentype = GENERATE_SERVICE_AND_MANAGER;
+        if (isNotificationChildNodePresent(this)) {
+            gentype = GENERATE_SERVICE_AND_MANAGER | GENERATE_EVENT_SUBJECT_CLASS | GENERATE_EVENT_CLASS
+                    | GENERATE_EVENT_LISTENER_INTERFACE;
+        }
+        getJavaFileInfo().setGeneratedFileTypes(gentype);
     }
 
     /**
@@ -136,6 +154,15 @@
      */
     @Override
     public void generateCodeExit() throws TranslatorException {
+        /**
+         * As part of the notification support the following files needs to be generated.
+         * 1) Subject of the notification(event), this is simple interface with builder class.
+         * 2) Event class extending "AbstractEvent" and defining event type enum.
+         * 3) Event listener interface extending "EventListener".
+         * 4) Event subject class.
+         *
+         * The manager class needs to extend the "ListenerRegistry".
+         */
         try {
             getTempJavaCodeFragmentFiles().generateJavaFile(GENERATE_SERVICE_AND_MANAGER, this);
             searchAndDeleteTempDir(getJavaFileInfo().getBaseCodeGenPath() +
@@ -144,4 +171,44 @@
             throw new TranslatorException("Failed to generate code for submodule node " + this.getName());
         }
     }
+
+    /**
+     * Returns notifications node list.
+     *
+     * @return notification nodes
+     */
+    public List<YangNode> getNotificationNodes() {
+        return notificationNodes;
+    }
+
+    /**
+     * Adds to notification node list.
+     *
+     * @param curNode notification node
+     */
+    private void addToNotificaitonList(YangNode curNode) {
+        getNotificationNodes().add(curNode);
+    }
+
+    /**
+     * Checks if there is any rpc defined in the module or sub-module.
+     *
+     * @param rootNode root node of the data model
+     * @return status of rpc's existence
+     */
+    public boolean isNotificationChildNodePresent(YangNode rootNode) {
+        YangNode childNode = rootNode.getChild();
+
+        while (childNode != null) {
+            if (childNode instanceof YangNotification) {
+                addToNotificaitonList(childNode);
+            }
+            childNode = childNode.getNextSibling();
+        }
+
+        if (!getNotificationNodes().isEmpty()) {
+            return true;
+        }
+        return false;
+    }
 }