+/*
+ * Copyright (c) 2013 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.controller.netconf.client;
+
+import io.netty.util.concurrent.Future;
+import io.netty.util.concurrent.GlobalEventExecutor;
+import io.netty.util.concurrent.Promise;
+
+import java.util.ArrayDeque;
+import java.util.Queue;
+
+import javax.annotation.concurrent.GuardedBy;
+
+import org.opendaylight.controller.netconf.api.NetconfMessage;
+import org.opendaylight.controller.netconf.api.NetconfTerminationReason;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.common.base.Preconditions;
+
+public class SimpleNetconfClientSessionListener implements NetconfClientSessionListener {
+ private static final class RequestEntry {
+ final Promise<NetconfMessage> promise;
+ final NetconfMessage request;
+
+ public RequestEntry(Promise<NetconfMessage> future, NetconfMessage request) {
+ this.promise = Preconditions.checkNotNull(future);
+ this.request = Preconditions.checkNotNull(request);
+ }
+ }
+
+ private static final Logger logger = LoggerFactory.getLogger(SimpleNetconfClientSessionListener.class);
+
+ @GuardedBy("this")
+ private final Queue<RequestEntry> requests = new ArrayDeque<>();
+
+ @GuardedBy("this")
+ private NetconfClientSession clientSession;
+
+ @GuardedBy("this")
+ private void dispatchRequest() {
+ while (!requests.isEmpty()) {
+ final RequestEntry e = requests.peek();
+ if (e.promise.setUncancellable()) {
+ logger.debug("Sending message {}", e.request);
+ clientSession.sendMessage(e.request);
+ break;
+ }
+
+ logger.debug("Message {} has been cancelled, skipping it", e.request);
+ requests.poll();
+ }
+ }
+
+ @Override
+ public final synchronized void onSessionUp(NetconfClientSession clientSession) {
+ this.clientSession = Preconditions.checkNotNull(clientSession);
+ logger.debug("Client session {} went up", clientSession);
+ dispatchRequest();
+ }
+
+ private synchronized void tearDown(final Exception cause) {
+ final RequestEntry e = requests.poll();
+ if (e != null) {
+ e.promise.setFailure(cause);
+ }
+
+ this.clientSession = null;
+ }
+
+ @Override
+ public final void onSessionDown(NetconfClientSession clientSession, Exception e) {
+ logger.debug("Client Session {} went down unexpectedly", clientSession, e);
+ tearDown(e);
+ }
+
+ @Override
+ public final void onSessionTerminated(NetconfClientSession clientSession,
+ NetconfTerminationReason netconfTerminationReason) {
+ logger.debug("Client Session {} terminated, reason: {}", clientSession,
+ netconfTerminationReason.getErrorMessage());
+ tearDown(new RuntimeException(netconfTerminationReason.getErrorMessage()));
+ }
+
+ @Override
+ public synchronized void onMessage(NetconfClientSession session, NetconfMessage message) {
+ logger.debug("New message arrived: {}", message);
+
+ final RequestEntry e = requests.poll();
+ if (e != null) {
+ e.promise.setSuccess(message);
+ dispatchRequest();
+ } else {
+ logger.info("Ignoring unsolicited message {}", message);
+ }
+ }
+
+ final synchronized Future<NetconfMessage> sendRequest(NetconfMessage message) {
+ final RequestEntry req = new RequestEntry(GlobalEventExecutor.INSTANCE.<NetconfMessage>newPromise(), message);
+
+ requests.add(req);
+ if (clientSession != null) {
+ dispatchRequest();
+ }
+
+ return req.promise;
+ }
+}