/*
* Copyright (c) 2009, 2012 IBM Corp.
*
* 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
*
* Contributors:
* Dave Locke - initial API and implementation and/or initial documentation
*/
package org.eclipse.paho.client.mqttv3;
import java.util.Properties;
import javax.net.SocketFactory;
import org.eclipse.paho.client.mqttv3.logging.Logger;
import org.eclipse.paho.client.mqttv3.logging.LoggerFactory;
import org.eclipse.paho.client.mqttv3.persist.MqttDefaultFilePersistence;
import org.eclipse.paho.client.mqttv3.util.Debug;
/**
* Lightweight client for talking to an MQTT server using methods that block
* until an operation completes.
*
* <p>This class implements the blocking {@link IMqttClient} client interface where all
* actions block until they have completed (or timed out).
* This implementation is compatible with all Java SE runtimes from 1.4.2 and up.
* </p>
* <p>An application can connect to an MQTT server using:
* <ul>
* <li>A plain TCP socket
* <li>An secure SSL/TLS socket
* </ul>
* </p>
* <p>To enable messages to be delivered even across network and client restarts
* messages need to be safely stored until the message has been delivered at the requested
* quality of service. A pluggable persistence mechanism is provided to store the messages.
* </p>
* <p>By default {@link MqttDefaultFilePersistence} is used to store messages to a file.
* If persistence is set to null then messages are stored in memory and hence can be lost
* if the client, Java runtime or device shuts down.
* </p>
* <p>If connecting with {@link MqttConnectOptions#setCleanSession(boolean)} set to true it
* is safe to use memory persistence as all state it cleared when a client disconnects. If
* connecting with cleanSession set to false, to provide reliable message delivery
* then a persistent message store should be used such as the default one. </p>
* <p>The message store interface is pluggable. Different stores can be used by implementing
* the {@link MqttClientPersistence} interface and passing it to the clients constructor.
* </p>
*
* @see IMqttClient
*/
public class MqttClient implements IMqttClient { //), DestinationProvider {
protected MqttAsyncClient aClient = null; // Delegate implementation to MqttAsyncClient
protected long timeToWait = -1; // How long each method should wait for action to complete
final static String className = MqttClient.class.getName();
public Logger log = LoggerFactory.getLogger(LoggerFactory.MQTT_CLIENT_MSG_CAT,className);
/**
* Create an MqttClient that can be used to communicate with an MQTT server.
* <p>
* The address of a server can be specified on the constructor. Alternatively
* a list containing one or more servers can be specified using the
* {@link MqttConnectOptions#setServerURIs(String[]) setServerURIs} method
* on MqttConnectOptions.
*
* <p>The <code>serverURI</code> parameter is typically used with the
* the <code>clientId</code> parameter to form a key. The key
* is used to store and reference messages while they are being delivered.
* Hence the serverURI specified on the constructor must still be specified even if a list
* of servers is specified on an MqttConnectOptions object.
* The serverURI on the constructor must remain the same across
* restarts of the client for delivery of messages to be maintained from a given
* client to a given server or set of servers.
*
* <p>The address of the server to connect to is specified as a URI. Two types of
* connection are supported <code>tcp://</code> for a TCP connection and
* <code>ssl://</code> for a TCP connection secured by SSL/TLS.
* For example:
* <ul>
* <li><code>tcp://localhost:1883</code></li>
* <li><code>ssl://localhost:8883</code></li>
* </ul>
* If the port is not specified, it will
* default to 1883 for <code>tcp://</code>" URIs, and 8883 for <code>ssl://</code> URIs.
* </p>
*
* <p>
* A client identifier <code>clientId</code> must be specified and be less that 23 characters.
* It must be unique across all clients connecting to the same
* server. The clientId is used by the server to store data related to the client,
* hence it is important that the clientId remain the same when connecting to a server
* if durable subscriptions or reliable messaging are required.
* <p>A convenience method is provided to generate a random client id that
* should satisfy this criteria - {@link #generateClientId()}. As the client identifier
* is used by the server to identify a client when it reconnects, the client must use the
* same identifier between connections if durable subscriptions or reliable
* delivery of messages is required.
* </p>
* <p>
* In Java SE, SSL can be configured in one of several ways, which the
* client will use in the following order:
* </p>
* <ul>
* <li><strong>Supplying an <code>SSLSocketFactory</code></strong> - applications can
* use {@link MqttConnectOptions#setSocketFactory(SocketFactory)} to supply
* a factory with the appropriate SSL settings.</li>
* <li><strong>SSL Properties</strong> - applications can supply SSL settings as a
* simple Java Properties using {@link MqttConnectOptions#setSSLProperties(Properties)}.</li>
* <li><strong>Use JVM settings</strong> - There are a number of standard
* Java system properties that can be used to configure key and trust stores.</li>
* </ul>
*
* <p>In Java ME, the platform settings are used for SSL connections.</p>
*
* <p>An instance of the default persistence mechanism {@link MqttDefaultFilePersistence}
* is used by the client. To specify a different persistence mechanism or to turn
* off persistence, use the {@link #MqttClient(String, String, MqttClientPersistence)}
* constructor.
*
* @param serverURI the address of the server to connect to, specified as a URI. Can be overridden using
* {@link MqttConnectOptions#setServerURIs(String[])}
* @param clientId a client identifier that is unique on the server being connected to
* @throws IllegalArgumentException if the URI does not start with
* "tcp://", "ssl://" or "local://".
* @throws IllegalArgumentException if the clientId is null or is greater than 23 characters in length
* @throws MqttException if any other problem was encountered
*/
public MqttClient(String serverURI, String clientId) throws MqttException {
this(serverURI,clientId, new MqttDefaultFilePersistence());
}
/**
* Create an MqttClient that can be used to communicate with an MQTT server.
* <p>
* The address of a server can be specified on the constructor. Alternatively
* a list containing one or more servers can be specified using the
* {@link MqttConnectOptions#setServerURIs(String[]) setServerURIs} method
* on MqttConnectOptions.
*
* <p>The <code>serverURI</code> parameter is typically used with the
* the <code>clientId</code> parameter to form a key. The key
* is used to store and reference messages while they are being delivered.
* Hence the serverURI specified on the constructor must still be specified even if a list
* of servers is specified on an MqttConnectOptions object.
* The serverURI on the constructor must remain the same across
* restarts of the client for delivery of messages to be maintained from a given
* client to a given server or set of servers.
*
* <p>The address of the server to connect to is specified as a URI. Two types of
* connection are supported <code>tcp://</code> for a TCP connection and
* <code>ssl://</code> for a TCP connection secured by SSL/TLS.
* For example:
* <ul>
* <li><code>tcp://localhost:1883</code></li>
* <li><code>ssl://localhost:8883</code></li>
* </ul>
* If the port is not specified, it will
* default to 1883 for <code>tcp://</code>" URIs, and 8883 for <code>ssl://</code> URIs.
* </p>
*
* <p>
* A client identifier <code>clientId</code> must be specified and be less that 23 characters.
* It must be unique across all clients connecting to the same
* server. The clientId is used by the server to store data related to the client,
* hence it is important that the clientId remain the same when connecting to a server
* if durable subscriptions or reliable messaging are required.
* <p>A convenience method is provided to generate a random client id that
* should satisfy this criteria - {@link #generateClientId()}. As the client identifier
* is used by the server to identify a client when it reconnects, the client must use the
* same identifier between connections if durable subscriptions or reliable
* delivery of messages is required.
* </p>
* <p>
* In Java SE, SSL can be configured in one of several ways, which the
* client will use in the following order:
* </p>
* <ul>
* <li><strong>Supplying an <code>SSLSocketFactory</code></strong> - applications can
* use {@link MqttConnectOptions#setSocketFactory(SocketFactory)} to supply
* a factory with the appropriate SSL settings.</li>
* <li><strong>SSL Properties</strong> - applications can supply SSL settings as a
* simple Java Properties using {@link MqttConnectOptions#setSSLProperties(Properties)}.</li>
* <li><strong>Use JVM settings</strong> - There are a number of standard
* Java system properties that can be used to configure key and trust stores.</li>
* </ul>
*
* <p>In Java ME, the platform settings are used for SSL connections.</p>
* <p>
* A persistence mechanism is used to enable reliable messaging.
* For messages sent at qualities of service (QoS) 1 or 2 to be reliably delivered,
* messages must be stored (on both the client and server) until the delivery of the message
* is complete. If messages are not safely stored when being delivered then
* a failure in the client or server can result in lost messages. A pluggable
* persistence mechanism is supported via the {@link MqttClientPersistence}
* interface. An implementer of this interface that safely stores messages
* must be specified in order for delivery of messages to be reliable. In
* addition {@link MqttConnectOptions#setCleanSession(boolean)} must be set
* to false. In the event that only QoS 0 messages are sent or received or
* cleanSession is set to true then a safe store is not needed.
* </p>
* <p>An implementation of file-based persistence is provided in
* class {@link MqttDefaultFilePersistence} which will work in all Java SE based
* systems. If no persistence is needed, the persistence parameter
* can be explicitly set to <code>null</code>.</p>
*
* @param serverURI the address of the server to connect to, specified as a URI. Can be overridden using
* {@link MqttConnectOptions#setServerURIs(String[])}
* @param clientId a client identifier that is unique on the server being connected to
* @param persistence the persistence class to use to store in-flight message. If null then the
* default persistence mechanism is used
* @throws IllegalArgumentException if the URI does not start with
* "tcp://", "ssl://" or "local://"
* @throws IllegalArgumentException if the clientId is null or is greater than 23 characters in length
* @throws MqttException if any other problem was encountered
*/
public MqttClient(String serverURI, String clientId, MqttClientPersistence persistence) throws MqttException {
aClient = new MqttAsyncClient(serverURI, clientId, persistence);
}
/*
* @see IMqttClient#connect()
*/
public void connect() throws MqttSecurityException, MqttException {
this.connect(new MqttConnectOptions());
}
/*
* @see IMqttClient#connect(MqttConnectOptions)
*/
public void connect(MqttConnectOptions options) throws MqttSecurityException, MqttException {
aClient.connect(options, null, null).waitForCompletion(getTimeToWait());
}
/*
* @see IMqttClient#disconnect()
*/
public void disconnect() throws MqttException {
this.disconnect(30000);
}
/*
* @see IMqttClient#disconnect(long)
*/
public void disconnect(long quiesceTimeout) throws MqttException {
aClient.disconnect(quiesceTimeout, null, null).waitForCompletion();
}
/*
* @see IMqttClient#subscribe(String)
*/
public void subscribe(String topicFilter) throws MqttException {
this.subscribe(new String[] {topicFilter}, new int[] {1});
}
/*
* @see IMqttClient#subscribe(String[])
*/
public void subscribe(String[] topicFilters) throws MqttException {
int[] qos = new int[topicFilters.length];
for (int i=0; i<qos.length; i++) {
qos[i] = 1;
}
this.subscribe(topicFilters, qos);
}
/*
* @see IMqttClient#subscribe(String, int)
*/
public void subscribe(String topicFilter, int qos) throws MqttException {
this.subscribe(new String[] {topicFilter}, new int[] {qos});
}
/*
* @see IMqttClient#subscribe(String[], int[])
*/
public void subscribe(String[] topicFilters, int[] qos) throws MqttException {
aClient.subscribe(topicFilters, qos, null,null).waitForCompletion(getTimeToWait());
}
/*
* @see IMqttClient#unsubscribe(String)
*/
public void unsubscribe(String topicFilter) throws MqttException {
unsubscribe(new String[] {topicFilter});
}
/*
* @see IMqttClient#unsubscribe(String[])
*/
public void unsubscribe(String[] topicFilters) throws MqttException {
aClient.unsubscribe(topicFilters, null,null).waitForCompletion(getTimeToWait());
}
/*
* @see IMqttClient#publishBlock(String, byte[], int, boolean)
*/
public void publish(String topic, byte[] payload,int qos, boolean retained) throws MqttException,
MqttPersistenceException {
MqttMessage message = new MqttMessage(payload);
message.setQos(qos);
message.setRetained(retained);
this.publish(topic, message);
}
/*
* @see IMqttClient#publishBlock(String, MqttMessage)
*/
public void publish(String topic, MqttMessage message) throws MqttException,
MqttPersistenceException {
aClient.publish(topic, message, null, null).waitForCompletion(getTimeToWait());
}
/**
* Set the maximum time to wait for an action to complete.
* <p>Set the maximum time to wait for an action to complete before
* returning control to the invoking application. Control is returned
* when:
* <ul>
* <li>the action completes
* <li>or when the timeout if exceeded
* <li>or when the client is disconnect/shutdown
* <ul>
* The default value is -1 which means the action will not timeout.
* In the event of a timeout the action carries on running in the
* background until it completes. The timeout is used on methods that
* block while the action is in progress.
* </p>
* @param timeToWaitInMillis before the action times out. A value or 0 or -1 will wait until
* the action finishes and not timeout.
*/
public void setTimeToWait(long timeToWaitInMillis) throws IllegalArgumentException{
if (timeToWaitInMillis < -1) {
throw new IllegalArgumentException();
}
this.timeToWait = timeToWaitInMillis;
}
/**
* Return the maximum time to wait for an action to complete.
* @see MqttClient#setTimeToWait(long)
*/
public long getTimeToWait() {
return this.timeToWait;
}
/* (non-Javadoc)
* @see org.eclipse.paho.client.mqttv3.IMqttClient#close()
*/
public void close() throws MqttException {
aClient.close();
}
/* (non-Javadoc)
* @see org.eclipse.paho.client.mqttv3.IMqttClient#getClientId()
*/
public String getClientId() {
return aClient.getClientId();
}
/* (non-Javadoc)
* @see org.eclipse.paho.client.mqttv3.IMqttClient#getPendingDeliveryTokens()
*/
public IMqttDeliveryToken[] getPendingDeliveryTokens() {
return aClient.getPendingDeliveryTokens();
}
/* (non-Javadoc)
* @see org.eclipse.paho.client.mqttv3.IMqttClient#getServerURI()
*/
public String getServerURI() {
return aClient.getServerURI();
}
/* (non-Javadoc)
* @see org.eclipse.paho.client.mqttv3.IMqttClient#getTopic(java.lang.String)
*/
public MqttTopic getTopic(String topic) {
return aClient.getTopic(topic);
}
/* (non-Javadoc)
* @see org.eclipse.paho.client.mqttv3.IMqttClient#isConnected()
*/
public boolean isConnected() {
return aClient.isConnected();
}
/* (non-Javadoc)
* @see org.eclipse.paho.client.mqttv3.IMqttClient#setCallback(org.eclipse.paho.client.mqttv3.MqttCallback)
*/
public void setCallback(MqttCallback callback) {
aClient.setCallback(callback);
}
/**
* Returns a randomly generated client identifier based on the current user's login
* name and the system time.
* <p>When cleanSession is set to false, an application must ensure it uses the
* same client identifier when it reconnects to the server to resume state and maintain
* assured message delivery.</p>
* @return a generated client identifier
* @see MqttConnectOptions#setCleanSession(boolean)
*/
public static String generateClientId() {
return MqttAsyncClient.generateClientId();
}
/**
* Return a debug object that can be used to help solve problems.
*/
public Debug getDebug() {
return (aClient.getDebug());
}
}