Renamed networkgraph package to topology.
Moved NetworkGraphPublisher into new topology package.
net.onrc.onos.ofcontroller.networkgraph.* => net.onrc.onos.core.topology.*
net.onrc.onos.ofcontroller.floodlightlistener.NetworkGraphPublisher => net.onrc.onos.core.topology.NetworkGraphPublisher
Change-Id: I8b156d0fcbba520fee61e92ab659bb02cfa704ac
diff --git a/src/main/java/net/onrc/onos/core/topology/Device.java b/src/main/java/net/onrc/onos/core/topology/Device.java
new file mode 100644
index 0000000..25a27be
--- /dev/null
+++ b/src/main/java/net/onrc/onos/core/topology/Device.java
@@ -0,0 +1,49 @@
+package net.onrc.onos.core.topology;
+
+import java.net.InetAddress;
+import java.util.Collection;
+
+import net.floodlightcontroller.util.MACAddress;
+
+/**
+ * Interface of Device Object exposed to the "NB" read-only Topology.
+ *
+ * TODO What a Device Object represent is unclear at the moment.
+ *
+ * Everything returned by these interfaces must be either Unmodifiable view,
+ * immutable object, or a copy of the original "SB" In-memory Topology.
+ *
+ */
+public interface Device {
+ /**
+ * Get the device MAC address.
+ *
+ * @return the device MAC address.
+ */
+ public MACAddress getMacAddress();
+
+ /**
+ * Get the device IP addresses.
+ *
+ * @return the device IP addresses.
+ */
+ public Collection<InetAddress> getIpAddress();
+
+ /**
+ * Get the device attachment points.
+ *
+ * Add requirement for Iteration order? Latest observed port first.
+ *
+ * @return the device attachment points.
+ */
+ public Iterable<Port> getAttachmentPoints();
+
+ /**
+ * Get the device last seen time.
+ *
+ * TODO: what is the time definition?
+ *
+ * @return the device last seen time.
+ */
+ public long getLastSeenTime();
+}