Additions to southbound API interfaces

added API interfaces for topology

added rough API interfaces for flow

Change-Id: I84ee2b70dd33dcbca98c1863e7f1766cc02642c5

+package net.onrc.onos.api.flow;
+
+package net.onrc.onos.api.Description;
+
+/**
+ * Information about a flow rule.
+ */
+public interface FlowDescription extends Description {
+
+    // Match and action, possibly reason for flow rule, unless reason is too OF-specific.
+
+}

+package net.onrc.onos.api.flow;
+
+import net.onrc.onos.api.Provider;
+
+/**
+ * Abstraction of a flow rule provider.
+ */
+public interface FlowRuleProvider extends Provider {
+}
\ No newline at end of file

+package net.onrc.onos.api.flow;
+
+import net.onrc.onos.api.ProviderBroker;
+
+/**
+ * Abstraction for a flow rule provider brokerage.
+ */
+public interface FlowRuleProviderBroker
+        extends ProviderBroker<FlowRuleProvider, FlowRuleProviderService> {
+}

+package net.onrc.onos.api.flow;
+
+import net.onrc.onos.api.ProviderService;
+
+/**
+ * Service through which flowrule providers can inject flowrule information into
+ * the core.
+ */
+public interface FlowRuleProviderService extends ProviderService {
+
+    /**
+     * Signals that a flow that was previously installed has been removed.
+     *
+     * @param flowDescription information about the removed flow
+     */
+    void flowRemoved(FlowDescription flowDescription);
+
+    /**
+     * Signals that a flowrule is missing for some network traffic.
+     *
+     * @param flowDescription information about traffic in need of flow rule(s)
+     */
+    void flowMissing(FlowDescription flowDescription);
+
+    /**
+     * Signals that a flowrule has been added.
+     *
+     * TODO  think about if this really makes sense, e.g. if stats collection or
+     * something can leverage it.
+     *
+     * @param flowDescription the rule that was added
+     */
+    void flowAdded(FlowDescription flowDescription);
+
+}
\ No newline at end of file

+package net.onrc.onos.api.topology;
+
+import net.onrc.onos.api.Description;
+
+import java.util.Collection;
+
+/**
+ * Describes attribute(s) of a network topology.
+ */
+public interface TopologyDescription extends Description {
+
+    /**
+     * A collection of Device, Link, and Host descriptors that describe
+     * the changes tha have occurred in the network topology.
+     *
+     * @return network element descriptions describing topology change
+     */
+    Collection<Description> details();
+
+}
\ No newline at end of file

+package net.onrc.onos.api.topology;
+
+import net.onrc.onos.api.Provider;
+
+/**
+ * Means for injecting topology information into the core.
+ */
+public interface TopologyProvider extends Provider {
+
+}

+package net.onrc.onos.api.topology;
+
+import net.onrc.onos.api.ProviderBroker;
+
+/**
+ * Abstraction of a network topology provider brokerage.
+ */
+public interface TopologyProviderBroker extends
+        ProviderBroker<TopologyProvider, TopologyProviderService> {
+}

+package net.onrc.onos.api.topology;
+
+import net.onrc.onos.api.ProviderService;
+
+/**
+ * Means for injecting topology information into the core.
+ */
+public interface TopologyProviderService extends ProviderService {
+
+    // What can be conveyed in a topology that isn't by individual
+    // providers?
+
+    /**
+     * Signals the core that some aspect of the topology has changed.
+     *
+     * @param topoDescription information about topology
+     */
+    void topologyChanged(TopologyDescription topoDescription);
+
+}