/**
* Copyright 2012-2013 Florian Schmaus
*
* All rights reserved. Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jivesoftware.smackx.ping;
import java.util.Collections;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.concurrent.ScheduledExecutorService;
import org.jivesoftware.smack.Connection;
import org.jivesoftware.smack.ConnectionCreationListener;
import org.jivesoftware.smack.PacketListener;
import org.jivesoftware.smack.SmackConfiguration;
import org.jivesoftware.smack.SmackError;
import org.jivesoftware.smack.XMPPException;
import org.jivesoftware.smack.filter.AndFilter;
import org.jivesoftware.smack.filter.IQTypeFilter;
import org.jivesoftware.smack.filter.PacketFilter;
import org.jivesoftware.smack.filter.PacketTypeFilter;
import org.jivesoftware.smack.keepalive.KeepAliveManager;
import org.jivesoftware.smack.packet.IQ;
import org.jivesoftware.smack.packet.Packet;
import org.jivesoftware.smack.packet.IQ.Type;
import org.jivesoftware.smack.ping.packet.Ping;
import org.jivesoftware.smack.util.SyncPacketSend;
import org.jivesoftware.smackx.ServiceDiscoveryManager;
import org.jivesoftware.smackx.packet.DiscoverInfo;
/**
* Implements the XMPP Ping as defined by XEP-0199. The XMPP Ping protocol
* allows one entity to 'ping' any other entity by simply sending a ping to
* the appropriate JID.
* <p>
* NOTE: The {@link KeepAliveManager} already provides a keepalive functionality
* for regularly pinging the server to keep the underlying transport connection
* alive. This class is specifically intended to do manual pings of other
* entities.
*
* @author Florian Schmaus
* @see <a href="http://www.xmpp.org/extensions/xep-0199.html">XEP-0199:XMPP
* Ping</a>
*/
public class PingManager {
private static Map<Connection, PingManager> instances = Collections
.synchronizedMap(new WeakHashMap<Connection, PingManager>());
static {
Connection.addConnectionCreationListener(new ConnectionCreationListener() {
public void connectionCreated(Connection connection) {
new PingManager(connection);
}
});
}
private Connection connection;
/**
* Retrieves a {@link PingManager} for the specified {@link Connection}, creating one if it doesn't already
* exist.
*
* @param connection
* The connection the manager is attached to.
* @return The new or existing manager.
*/
public synchronized static PingManager getInstanceFor(Connection connection) {
PingManager pingManager = instances.get(connection);
if (pingManager == null) {
pingManager = new PingManager(connection);
}
return pingManager;
}
private PingManager(Connection con) {
this.connection = con;
ServiceDiscoveryManager sdm = ServiceDiscoveryManager.getInstanceFor(connection);
// The ServiceDiscoveryManager was not pre-initialized
if (sdm == null)
sdm = new ServiceDiscoveryManager(connection);
sdm.addFeature(Ping.NAMESPACE);
PacketFilter pingPacketFilter = new AndFilter(new PacketTypeFilter(Ping.class), new IQTypeFilter(Type.GET));
connection.addPacketListener(new PacketListener() {
/**
* Sends a Pong for every Ping
*/
public void processPacket(Packet packet) {
IQ pong = IQ.createResultIQ((Ping) packet);
connection.sendPacket(pong);
}
}, pingPacketFilter);
}
/**
* Pings the given jid. This method will return false if an error occurs. The exception
* to this, is a server ping, which will always return true if the server is reachable,
* event if there is an error on the ping itself (i.e. ping not supported).
* <p>
* Use {@link #isPingSupported(String)} to determine if XMPP Ping is supported
* by the entity.
*
* @param jid The id of the entity the ping is being sent to
* @param pingTimeout The time to wait for a reply
* @return true if a reply was received from the entity, false otherwise.
*/
public boolean ping(String jid, long pingTimeout) {
Ping ping = new Ping(jid);
try {
SyncPacketSend.getReply(connection, ping);
}
catch (XMPPException exc) {
return (jid.equals(connection.getServiceName()) && (exc.getSmackError() != SmackError.NO_RESPONSE_FROM_SERVER));
}
return true;
}
/**
* Same as calling {@link #ping(String, long)} with the defaultpacket reply
* timeout.
*
* @param jid The id of the entity the ping is being sent to
* @return true if a reply was received from the entity, false otherwise.
*/
public boolean ping(String jid) {
return ping(jid, SmackConfiguration.getPacketReplyTimeout());
}
/**
* Query the specified entity to see if it supports the Ping protocol (XEP-0199)
*
* @param jid The id of the entity the query is being sent to
* @return true if it supports ping, false otherwise.
* @throws XMPPException An XMPP related error occurred during the request
*/
public boolean isPingSupported(String jid) throws XMPPException {
DiscoverInfo result = ServiceDiscoveryManager.getInstanceFor(connection).discoverInfo(jid);
return result.containsFeature(Ping.NAMESPACE);
}
/**
* Pings the server. This method will return true if the server is reachable. It
* is the equivalent of calling <code>ping</code> with the XMPP domain.
* <p>
* Unlike the {@link #ping(String)} case, this method will return true even if
* {@link #isPingSupported(String)} is false.
*
* @return true if a reply was received from the server, false otherwise.
*/
public boolean pingMyServer() {
return ping(connection.getServiceName());
}
}