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/Link.java b/src/main/java/net/onrc/onos/core/topology/Link.java
new file mode 100644
index 0000000..f73bccf
--- /dev/null
+++ b/src/main/java/net/onrc/onos/core/topology/Link.java
@@ -0,0 +1,66 @@
+package net.onrc.onos.core.topology;
+
+/**
+ * Interface of Link Object exposed to the "NB" read-only Topology.
+ *
+ * Everything returned by these interfaces must be either Unmodifiable view,
+ * immutable object, or a copy of the original "SB" In-memory Topology.
+ *
+ */
+public interface Link {
+ /**
+ * Get the source switch for the link.
+ *
+ * @return the source switch for the link.
+ */
+ public Switch getSrcSwitch();
+
+ /**
+ * Get the source port for the link.
+ *
+ * @return the source port for the link.
+ */
+ public Port getSrcPort();
+
+ /**
+ * Get the destination switch for the link.
+ *
+ * @return the destination switch for the link.
+ */
+ public Switch getDstSwitch();
+
+ /**
+ * Get the destination port for the link.
+ *
+ * @return the destination port for the link.
+ */
+ public Port getDstPort();
+
+ /**
+ * Get the last seen time for the link.
+ *
+ * TODO: Not implemented yet.
+ * TODO: what is the time definition?
+ *
+ * @return the last seen time for the link.
+ */
+ public long getLastSeenTime();
+
+ /**
+ * Get the link cost.
+ *
+ * TODO: What is the unit?
+ *
+ * @param return the link cost.
+ */
+ public int getCost();
+
+ /**
+ * Get the link capacity.
+ *
+ * TODO: What is the unit?
+ *
+ * @return the link capacity.
+ */
+ public Double getCapacity();
+}