diff --git a/protocol/invocation/rpcinvocation.go b/protocol/invocation/rpcinvocation.go
index 503ff0323644537e14a9e71c288b5a51f0bf7557..a9b8695da92d973f2b59f61dbc95173cfcc17027 100644
--- a/protocol/invocation/rpcinvocation.go
+++ b/protocol/invocation/rpcinvocation.go
@@ -31,15 +31,15 @@ import (
 /////////////////////////////
 // todo: is it necessary to separate fields of consumer(provider) from RPCInvocation
 type RPCInvocation struct {
-	methodName     string
-	parameterTypes []reflect.Type
+	methodName      string
+	parameterTypes  []reflect.Type
 	parameterValues []reflect.Value
-	arguments      []interface{}
-	reply          interface{}
-	callBack       interface{}
-	attachments    map[string]string
-	invoker        protocol.Invoker
-	lock           sync.RWMutex
+	arguments       []interface{}
+	reply           interface{}
+	callBack        interface{}
+	attachments     map[string]string
+	invoker         protocol.Invoker
+	lock            sync.RWMutex
 }
 
 func NewRPCInvocation(methodName string, arguments []interface{}, attachments map[string]string) *RPCInvocation {