diff --git a/java_gen/templates/custom/interface/OFPortDesc.java b/java_gen/templates/custom/interface/OFPortDesc.java
index ecf39f3..247464d 100644
--- a/java_gen/templates/custom/interface/OFPortDesc.java
+++ b/java_gen/templates/custom/interface/OFPortDesc.java
@@ -1,2 +1,23 @@
-    // Additional method
-    boolean isEnabled();
\ No newline at end of file
+    // Additional methods
+
+    /**
+     * Returns true if the port is up, i.e., it's neither administratively
+     * down nor link down. It currently does NOT take STP state into
+     * consideration
+     * @return whether the port is up
+     */
+    boolean isEnabled();
+
+    /**
+     * Returns the current generation ID of this port.
+     *
+     * The generationId is reported by the switch as a @{link OFPortDescProp} in
+     * @link{OFPortDescStatsReply} and @link{OFPortStatus} messages. If the
+     * current OFPortDesc does not contain a generation Id, returns U64.ZERO;
+     *
+     * For OpenFlow versions earlier than 1.4, always returns U64.ZERO;
+     *
+     * @return the generation ID or U64.ZERO if not reported
+     * @since 1.4
+     */
+     public U64 getBsnGenerationId();