Remove opendaylight directory

[netconf.git] / restconf / sal-rest-connector / src / main / java / org / opendaylight / netconf / sal / streams / listeners / Notificator.java

diff --git a/restconf/sal-rest-connector/src/main/java/org/opendaylight/netconf/sal/streams/listeners/Notificator.java b/restconf/sal-rest-connector/src/main/java/org/opendaylight/netconf/sal/streams/listeners/Notificator.java
new file mode 100644 (file)
index 0000000..9537732
--- /dev/null
+++ b/restconf/sal-rest-connector/src/main/java/org/opendaylight/netconf/sal/streams/listeners/Notificator.java
@@ -0,0 +1,150 @@
+/*
+ * Copyright (c) 2014 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.netconf.sal.streams.listeners;
+
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
+
+/**
+ * {@link Notificator} is responsible to create, remove and find
+ * {@link ListenerAdapter} listener.
+ */
+public class Notificator {
+
+    private static Map<String, ListenerAdapter> listenersByStreamName = new ConcurrentHashMap<>();
+    private static final Lock lock = new ReentrantLock();
+
+    private Notificator() {
+    }
+
+    /**
+     * Returns list of all stream names
+     */
+    public static Set<String> getStreamNames() {
+        return listenersByStreamName.keySet();
+    }
+
+    /**
+     * Gets {@link ListenerAdapter} specified by stream name.
+     *
+     * @param streamName
+     *            The name of the stream.
+     * @return {@link ListenerAdapter} specified by stream name.
+     */
+    public static ListenerAdapter getListenerFor(String streamName) {
+        return listenersByStreamName.get(streamName);
+    }
+
+    /**
+     * Checks if the listener specified by {@link YangInstanceIdentifier} path exist.
+     *
+     * @param streamName
+     * @return True if the listener exist, false otherwise.
+     */
+    public static boolean existListenerFor(String streamName) {
+        return listenersByStreamName.containsKey(streamName);
+    }
+
+    /**
+     * Creates new {@link ListenerAdapter} listener from {@link YangInstanceIdentifier} path and stream name.
+     *
+     * @param path
+     *            Path to data in data repository.
+     * @param streamName
+     *            The name of the stream.
+     * @return New {@link ListenerAdapter} listener from {@link YangInstanceIdentifier} path and stream name.
+     */
+    public static ListenerAdapter createListener(YangInstanceIdentifier path, String streamName) {
+        ListenerAdapter listener = new ListenerAdapter(path, streamName);
+        try {
+            lock.lock();
+            listenersByStreamName.put(streamName, listener);
+        } finally {
+            lock.unlock();
+        }
+        return listener;
+    }
+
+    /**
+     * Looks for listener determined by {@link YangInstanceIdentifier} path and removes it.
+     * Creates String representation of stream name from URI. Removes slash from URI in start and end position.
+     *
+     * @param uri
+     *            URI for creation stream name.
+     * @return String representation of stream name.
+     */
+    public static String createStreamNameFromUri(String uri) {
+        if (uri == null) {
+            return null;
+        }
+        String result = uri;
+        if (result.startsWith("/")) {
+            result = result.substring(1);
+        }
+        if (result.endsWith("/")) {
+            result = result.substring(0, result.length()-1);
+        }
+        return result;
+    }
+
+    /**
+     * Removes all listeners.
+     */
+    public static void removeAllListeners() {
+        for (ListenerAdapter listener : listenersByStreamName.values()) {
+            try {
+                listener.close();
+            } catch (Exception e) {
+            }
+        }
+        try {
+            lock.lock();
+            listenersByStreamName = new ConcurrentHashMap<>();
+        } finally {
+            lock.unlock();
+        }
+    }
+
+    /**
+     * Checks if listener has at least one subscriber. In case it doesn't have any, delete listener.
+     *
+     * @param listener
+     *            ListenerAdapter
+     */
+    public static void removeListenerIfNoSubscriberExists(ListenerAdapter listener) {
+        if (!listener.hasSubscribers()) {
+            deleteListener(listener);
+        }
+    }
+
+    /**
+     * Delete {@link ListenerAdapter} listener specified in parameter.
+     *
+     * @param listener
+     *            ListenerAdapter
+     */
+    private static void deleteListener(ListenerAdapter listener) {
+        if (listener != null) {
+            try {
+                listener.close();
+            } catch (Exception e) {
+            }
+            try {
+                lock.lock();
+                listenersByStreamName.remove(listener.getStreamName());
+            } finally {
+                lock.unlock();
+            }
+        }
+    }
+
+}