added VLANID construct

Change-Id: Ia58abb268d52639215f289052bbf8802992f98a6
diff --git a/core/trivial/src/main/java/org/onlab/onos/net/trivial/host/impl/SimpleHostManager.java b/core/trivial/src/main/java/org/onlab/onos/net/trivial/host/impl/SimpleHostManager.java
index 0bb291f1..3032ac9 100644
--- a/core/trivial/src/main/java/org/onlab/onos/net/trivial/host/impl/SimpleHostManager.java
+++ b/core/trivial/src/main/java/org/onlab/onos/net/trivial/host/impl/SimpleHostManager.java
@@ -23,6 +23,7 @@
 import org.onlab.onos.net.provider.AbstractProviderService;
 import org.onlab.packet.IPAddress;
 import org.onlab.packet.MACAddress;
+import org.onlab.packet.VLANID;
 import org.slf4j.Logger;
 
 import java.util.Set;
@@ -85,7 +86,7 @@
     }
 
     @Override
-    public Set<Host> getHostsByVlan(long vlanId) {
+    public Set<Host> getHostsByVlan(VLANID vlanId) {
         return store.getHosts(vlanId);
     }