diff --git a/framework/src/android/net/QosSession.java b/framework/src/android/net/QosSession.java
index 25f3965..d1edae9 100644
--- a/framework/src/android/net/QosSession.java
+++ b/framework/src/android/net/QosSession.java
@@ -22,6 +22,9 @@
 import android.os.Parcel;
 import android.os.Parcelable;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
 /**
  * Provides identifying information of a QoS session.  Sent to an application through
  * {@link QosCallback}.
@@ -107,6 +110,7 @@
             TYPE_EPS_BEARER,
             TYPE_NR_BEARER,
     })
+    @Retention(RetentionPolicy.SOURCE)
     @interface QosSessionType {}
 
     private QosSession(final Parcel in) {