Added notion of a general Store abstraction and wired it up in ClusterStore.
diff --git a/core/api/src/main/java/org/onlab/onos/cluster/ClusterStore.java b/core/api/src/main/java/org/onlab/onos/cluster/ClusterStore.java
index 4579190..ea5bbd3 100644
--- a/core/api/src/main/java/org/onlab/onos/cluster/ClusterStore.java
+++ b/core/api/src/main/java/org/onlab/onos/cluster/ClusterStore.java
@@ -1,11 +1,13 @@
package org.onlab.onos.cluster;
+import org.onlab.onos.store.Store;
+
import java.util.Set;
/**
* Manages inventory of controller cluster nodes; not intended for direct use.
*/
-public interface ClusterStore {
+public interface ClusterStore extends Store<ClusterEvent, ClusterStoreDelegate> {
/**
* Returns the local controller node.
diff --git a/core/api/src/main/java/org/onlab/onos/cluster/ClusterStoreDelegate.java b/core/api/src/main/java/org/onlab/onos/cluster/ClusterStoreDelegate.java
new file mode 100644
index 0000000..b247c27
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/cluster/ClusterStoreDelegate.java
@@ -0,0 +1,9 @@
+package org.onlab.onos.cluster;
+
+import org.onlab.onos.store.StoreDelegate;
+
+/**
+ * Cluster store delegate abstraction.
+ */
+public interface ClusterStoreDelegate extends StoreDelegate<ClusterEvent> {
+}
diff --git a/core/api/src/main/java/org/onlab/onos/cluster/MastershipStoreDelegate.java b/core/api/src/main/java/org/onlab/onos/cluster/MastershipStoreDelegate.java
new file mode 100644
index 0000000..b4d923c
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/cluster/MastershipStoreDelegate.java
@@ -0,0 +1,9 @@
+package org.onlab.onos.cluster;
+
+import org.onlab.onos.store.StoreDelegate;
+
+/**
+ * Mastership store delegate abstraction.
+ */
+public interface MastershipStoreDelegate extends StoreDelegate<MastershipEvent> {
+}
diff --git a/core/api/src/main/java/org/onlab/onos/net/device/DeviceStoreDelegate.java b/core/api/src/main/java/org/onlab/onos/net/device/DeviceStoreDelegate.java
new file mode 100644
index 0000000..4ab8486
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/net/device/DeviceStoreDelegate.java
@@ -0,0 +1,9 @@
+package org.onlab.onos.net.device;
+
+import org.onlab.onos.store.StoreDelegate;
+
+/**
+ * Infrastructure device store delegate abstraction.
+ */
+public interface DeviceStoreDelegate extends StoreDelegate<DeviceEvent> {
+}
diff --git a/core/api/src/main/java/org/onlab/onos/store/AbstractStore.java b/core/api/src/main/java/org/onlab/onos/store/AbstractStore.java
new file mode 100644
index 0000000..efd0d03
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/store/AbstractStore.java
@@ -0,0 +1,33 @@
+package org.onlab.onos.store;
+
+import org.onlab.onos.event.Event;
+
+/**
+ * Base implementation of a store.
+ */
+public class AbstractStore<E extends Event, D extends StoreDelegate<E>>
+ implements Store<E, D> {
+
+ protected D delegate;
+
+ @Override
+ public void setDelegate(D delegate) {
+ this.delegate = delegate;
+ }
+
+ @Override
+ public D getDelegate() {
+ return delegate;
+ }
+
+ /**
+ * Notifies the delegate with the specified event.
+ *
+ * @param event event to delegate
+ */
+ protected void notifyDelegate(E event) {
+ if (delegate != null) {
+ delegate.notify(event);
+ }
+ }
+}
diff --git a/core/api/src/main/java/org/onlab/onos/store/Store.java b/core/api/src/main/java/org/onlab/onos/store/Store.java
new file mode 100644
index 0000000..9eaef66
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/store/Store.java
@@ -0,0 +1,25 @@
+package org.onlab.onos.store;
+
+import org.onlab.onos.event.Event;
+
+/**
+ * Abstraction of a entity capable of storing and/or distributing information
+ * across a cluster.
+ */
+public interface Store<E extends Event, D extends StoreDelegate<E>> {
+
+ /**
+ * Sets the delegate on the store.
+ *
+ * @param delegate new store delegate
+ */
+ void setDelegate(D delegate);
+
+ /**
+ * Get the current store delegate.
+ *
+ * @return store delegate
+ */
+ D getDelegate();
+
+}
diff --git a/core/api/src/main/java/org/onlab/onos/store/StoreDelegate.java b/core/api/src/main/java/org/onlab/onos/store/StoreDelegate.java
new file mode 100644
index 0000000..e2c5cd3
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/store/StoreDelegate.java
@@ -0,0 +1,13 @@
+package org.onlab.onos.store;
+
+import org.onlab.onos.event.Event;
+
+/**
+ * Entity associated with a store and capable of receiving notifications of
+ * events within the store.
+ */
+public interface StoreDelegate<E extends Event> {
+
+ void notify(E event);
+
+}
diff --git a/core/api/src/main/java/org/onlab/onos/store/package-info.java b/core/api/src/main/java/org/onlab/onos/store/package-info.java
new file mode 100644
index 0000000..7e767f0
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/store/package-info.java
@@ -0,0 +1,4 @@
+/**
+ * Abstractions for creating and interacting with distributed stores.
+ */
+package org.onlab.onos.store;
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