ONOS-4512 fix bug to get and delete

Change-Id: I952085be7548830b660e133cf1c59fcdf98e8f69
diff --git a/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/FlowClassifierWebResource.java b/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/FlowClassifierWebResource.java
index 10cb399..b3b2bcb 100644
--- a/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/FlowClassifierWebResource.java
+++ b/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/FlowClassifierWebResource.java
@@ -59,6 +59,7 @@
      * @return 200 OK
      */
     @GET
+    @Consumes(MediaType.APPLICATION_JSON)
     @Produces(MediaType.APPLICATION_JSON)
     public Response getFlowClassifiers() {
         Iterable<FlowClassifier> flowClassifiers = get(FlowClassifierService.class).getFlowClassifiers();
@@ -81,6 +82,7 @@
      */
     @GET
     @Path("{flow_id}")
+    @Consumes(MediaType.APPLICATION_JSON)
     @Produces(MediaType.APPLICATION_JSON)
     public Response getFlowClassifier(@PathParam("flow_id") String id) {
         FlowClassifier flowClassifier = nullIsNotFound(get(FlowClassifierService.class)
@@ -154,6 +156,8 @@
      */
     @Path("{flow_id}")
     @DELETE
+    @Produces(MediaType.APPLICATION_JSON)
+    @Consumes(MediaType.APPLICATION_JSON)
     public Response deleteFlowClassifier(@PathParam("flow_id") String id) {
         log.debug("Deletes flow classifier by identifier {}.", id);
         FlowClassifierId flowClassifierId = FlowClassifierId.of(id);