check for invalid masks in getSubnetBroadcastAddress in IPAWithMask
diff --git a/java_gen/pre-written/src/test/java/org/projectfloodlight/openflow/types/IPv4AddressTest.java b/java_gen/pre-written/src/test/java/org/projectfloodlight/openflow/types/IPv4AddressTest.java
index bd2c945..a57b42a 100644
--- a/java_gen/pre-written/src/test/java/org/projectfloodlight/openflow/types/IPv4AddressTest.java
+++ b/java_gen/pre-written/src/test/java/org/projectfloodlight/openflow/types/IPv4AddressTest.java
@@ -359,5 +359,13 @@
         } catch (NullPointerException e) {
             assertNotNull(e.getMessage());
         }
+        try {
+            IPv4AddressWithMask.of(IPv4Address.of("10.10.10.0"),
+                                   IPv4Address.of("255.0.255.0"))
+                                   .getSubnetBroadcastAddress();
+            fail("Should have thrown IllegalArgumentException");
+        } catch (IllegalArgumentException e) {
+            assertNotNull(e.getMessage());
+        }
     }
 }