BUG-6650: ep-sgt/ip, propose initial sxp-ep-provider

[groupbasedpolicy.git] / sxp-integration / sxp-ep-provider / src / main / java / org / opendaylight / groupbasedpolicy / sxp / ep / provider / impl / SimpleCachedDao.java

diff --git a/sxp-integration/sxp-ep-provider/src/main/java/org/opendaylight/groupbasedpolicy/sxp/ep/provider/impl/SimpleCachedDao.java b/sxp-integration/sxp-ep-provider/src/main/java/org/opendaylight/groupbasedpolicy/sxp/ep/provider/impl/SimpleCachedDao.java
new file mode 100644 (file)
index 0000000..913274b
--- /dev/null
+++ b/sxp-integration/sxp-ep-provider/src/main/java/org/opendaylight/groupbasedpolicy/sxp/ep/provider/impl/SimpleCachedDao.java
@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2016 Cisco Systems, Inc. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+
+package org.opendaylight.groupbasedpolicy.sxp.ep.provider.impl;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+/**
+ * Purpose: encapsulate access to DS by exposing
+ * <dl>
+ * <dt>find</dt>
+ * <dd>search through cached values</dd>
+ * <dt>update</dt>
+ * <dd>stores given pair (key, value) to local cache</dd>
+ * </dl>
+ *
+ * @param <K> data key type
+ * @param <V> data type
+ */
+public interface SimpleCachedDao<K, V> extends SimpleDao<K, V> {
+
+    /**
+     * store given pair to local cache
+     *
+     * @param key   associated to value
+     * @param value associated to key
+     */
+    V update(@Nonnull K key, @Nullable V value);
+
+    /**
+     * invalidate all cache entries
+     */
+    void invalidateCache();
+
+    /**
+     * @return true if there is nothing cached
+     */
+    boolean isEmpty();
+
+    /**
+     * @return unmodifiable iterator through all cached values
+     */
+    Iterable<V> values();
+}