diff --git a/adapter/adapter.go b/adapter/adapter.go
index 3ef5a4f..ae785c0 100644
--- a/adapter/adapter.go
+++ b/adapter/adapter.go
@@ -49,8 +49,8 @@ type Adapter struct {
 	mx                sync.Mutex
 }
 
-func (a *Adapter) SetChannel(hchan *chan interface{}) {
-	a.mx.Lock()
-	defer a.mx.Unlock()
-	a.Channel = hchan
+func (h *Adapter) SetChannel(hchan *chan interface{}) {
+	h.mx.Lock()
+	defer h.mx.Unlock()
+	h.Channel = hchan
 }
diff --git a/adapter/oam.go b/adapter/oam.go
index 434d1c1..14f1d8e 100644
--- a/adapter/oam.go
+++ b/adapter/oam.go
@@ -104,14 +104,13 @@ func (or *OAMRegistrant) Register() error {
 		if err != nil {
 			return ErrOpenOAMDefintionFile(err)
 		}
-		defer func() {
-			_ = definition.Close()
-		}()
 
 		definitionMap := map[string]interface{}{}
 		if err := json.NewDecoder(definition).Decode(&definitionMap); err != nil {
+			_ = definition.Close()
 			return ErrJSONMarshal(err)
 		}
+		_ = definition.Close()
 		ord.OAMDefinition = definitionMap
 
 		schema, err := ioutil.ReadFile(dpath.OAMRefSchemaPath)