add methods to directly set MacAddress

Change-Id: Idab9dce493927d8943789177830df630f3b1326a
diff --git a/core/net/src/main/java/org/onlab/onos/net/host/impl/HostMonitor.java b/core/net/src/main/java/org/onlab/onos/net/host/impl/HostMonitor.java
index f28dcdb..a6af018 100644
--- a/core/net/src/main/java/org/onlab/onos/net/host/impl/HostMonitor.java
+++ b/core/net/src/main/java/org/onlab/onos/net/host/impl/HostMonitor.java
@@ -67,6 +67,7 @@
     private final ConcurrentMap<ProviderId, HostProvider> hostProviders;
 
     private static final long DEFAULT_PROBE_RATE = 30000; // milliseconds
+    private static final byte[] ZERO_MAC_ADDRESS = MacAddress.ZERO.toBytes();
     private long probeRate = DEFAULT_PROBE_RATE;
 
     private Timeout timeout;
@@ -215,15 +216,15 @@
            .setProtocolAddressLength((byte) IpAddress.INET_BYTE_LENGTH)
            .setOpCode(ARP.OP_REQUEST);
 
-        arp.setSenderHardwareAddress(sourceMac.getAddress())
+        arp.setSenderHardwareAddress(sourceMac.toBytes())
            .setSenderProtocolAddress(sourceIp.toOctets())
-           .setTargetHardwareAddress(MacAddress.ZERO_MAC_ADDRESS)
+           .setTargetHardwareAddress(ZERO_MAC_ADDRESS)
            .setTargetProtocolAddress(targetIp.toOctets());
 
         Ethernet ethernet = new Ethernet();
         ethernet.setEtherType(Ethernet.TYPE_ARP)
-                .setDestinationMACAddress(MacAddress.BROADCAST_MAC)
-                .setSourceMACAddress(sourceMac.getAddress())
+                .setDestinationMACAddress(MacAddress.BROADCAST)
+                .setSourceMACAddress(sourceMac)
                 .setPayload(arp);
 
         return ethernet;
diff --git a/core/net/src/main/java/org/onlab/onos/net/proxyarp/impl/ProxyArpManager.java b/core/net/src/main/java/org/onlab/onos/net/proxyarp/impl/ProxyArpManager.java
index 16e3798..0aae62d 100644
--- a/core/net/src/main/java/org/onlab/onos/net/proxyarp/impl/ProxyArpManager.java
+++ b/core/net/src/main/java/org/onlab/onos/net/proxyarp/impl/ProxyArpManager.java
@@ -360,8 +360,8 @@
             Ethernet request) {
 
         Ethernet eth = new Ethernet();
-        eth.setDestinationMACAddress(request.getSourceMACAddress());
-        eth.setSourceMACAddress(srcMac.getAddress());
+        eth.setDestinationMACAddress(request.getSourceMAC());
+        eth.setSourceMACAddress(srcMac);
         eth.setEtherType(Ethernet.TYPE_ARP);
         eth.setVlanID(request.getVlanID());
 
@@ -372,7 +372,7 @@
 
         arp.setProtocolAddressLength((byte) IpAddress.INET_BYTE_LENGTH);
         arp.setHardwareAddressLength((byte) Ethernet.DATALAYER_ADDRESS_LENGTH);
-        arp.setSenderHardwareAddress(srcMac.getAddress());
+        arp.setSenderHardwareAddress(srcMac.toBytes());
         arp.setTargetHardwareAddress(request.getSourceMACAddress());
 
         arp.setTargetProtocolAddress(((ARP) request.getPayload())