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/*******************************************************************************
 * Copyright (c) 2009, 2015 IBM Corp.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * and Eclipse Distribution License v1.0 which accompany this distribution. 
 *
 * The Eclipse Public License is available at 
 *    http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at 
 *   http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *    Dave Locke - initial API and implementation and/or initial documentation
 *    Ian Craggs - MQTT 3.1.1 support
 *    Ian Craggs - per subscription message handlers (bug 466579)
 *    Ian Craggs - ack control (bug 472172)
 */
package org.eclipse.paho.client.mqttv3;

import java.util.Properties;
import java.util.concurrent.ScheduledExecutorService;

import javax.net.SocketFactory;

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.
 *
 * 

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. *

*

An application can connect to an MQTT server using: *

    *
  • A plain TCP socket *
  • An secure SSL/TLS socket *
*

*

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. *

*

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. *

*

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.

*

The message store interface is pluggable. Different stores can be used by implementing * the {@link MqttClientPersistence} interface and passing it to the clients constructor. *

* * @see IMqttClient */ public class MqttClient implements IMqttClient { //), DestinationProvider { //private static final String CLASS_NAME = MqttClient.class.getName(); //private static final Logger log = LoggerFactory.getLogger(LoggerFactory.MQTT_CLIENT_MSG_CAT,CLASS_NAME); protected MqttAsyncClient aClient = null; // Delegate implementation to MqttAsyncClient protected long timeToWait = -1; // How long each method should wait for action to complete /** * Create an MqttClient that can be used to communicate with an MQTT server. *

* 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. * *

The serverURI parameter is typically used with the * the clientId 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. * *

The address of the server to connect to is specified as a URI. Two types of * connection are supported tcp:// for a TCP connection and * ssl:// for a TCP connection secured by SSL/TLS. * For example: *

    *
  • tcp://localhost:1883
  • *
  • ssl://localhost:8883
  • *
* If the port is not specified, it will * default to 1883 for tcp://" URIs, and 8883 for ssl:// URIs. *

* *

* A client identifier clientId must be specified and be less that 65535 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. *

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. *

*

* In Java SE, SSL can be configured in one of several ways, which the * client will use in the following order: *

*
    *
  • Supplying an SSLSocketFactory - applications can * use {@link MqttConnectOptions#setSocketFactory(SocketFactory)} to supply * a factory with the appropriate SSL settings.
  • *
  • SSL Properties - applications can supply SSL settings as a * simple Java Properties using {@link MqttConnectOptions#setSSLProperties(Properties)}.
  • *
  • Use JVM settings - There are a number of standard * Java system properties that can be used to configure key and trust stores.
  • *
* *

In Java ME, the platform settings are used for SSL connections.

* *

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 65535 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. *

* 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. * *

The serverURI parameter is typically used with the * the clientId 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. * *

The address of the server to connect to is specified as a URI. Two types of * connection are supported tcp:// for a TCP connection and * ssl:// for a TCP connection secured by SSL/TLS. * For example: *

    *
  • tcp://localhost:1883
  • *
  • ssl://localhost:8883
  • *
* If the port is not specified, it will * default to 1883 for tcp://" URIs, and 8883 for ssl:// URIs. *

* *

* A client identifier clientId must be specified and be less that 65535 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. *

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. *

*

* In Java SE, SSL can be configured in one of several ways, which the * client will use in the following order: *

*
    *
  • Supplying an SSLSocketFactory - applications can * use {@link MqttConnectOptions#setSocketFactory(SocketFactory)} to supply * a factory with the appropriate SSL settings.
  • *
  • SSL Properties - applications can supply SSL settings as a * simple Java Properties using {@link MqttConnectOptions#setSSLProperties(Properties)}.
  • *
  • Use JVM settings - There are a number of standard * Java system properties that can be used to configure key and trust stores.
  • *
* *

In Java ME, the platform settings are used for SSL connections.

*

* 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. *

*

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 null.

* * @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 65535 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); } /** * Create an MqttClient that can be used to communicate with an MQTT server. *

* 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. * *

The serverURI parameter is typically used with the * the clientId 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. * *

The address of the server to connect to is specified as a URI. Two types of * connection are supported tcp:// for a TCP connection and * ssl:// for a TCP connection secured by SSL/TLS. * For example: *

    *
  • tcp://localhost:1883
  • *
  • ssl://localhost:8883
  • *
* If the port is not specified, it will * default to 1883 for tcp://" URIs, and 8883 for ssl:// URIs. *

* *

* A client identifier clientId must be specified and be less that 65535 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. *

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. *

*

* In Java SE, SSL can be configured in one of several ways, which the * client will use in the following order: *

*
    *
  • Supplying an SSLSocketFactory - applications can * use {@link MqttConnectOptions#setSocketFactory(SocketFactory)} to supply * a factory with the appropriate SSL settings.
  • *
  • SSL Properties - applications can supply SSL settings as a * simple Java Properties using {@link MqttConnectOptions#setSSLProperties(Properties)}.
  • *
  • Use JVM settings - There are a number of standard * Java system properties that can be used to configure key and trust stores.
  • *
* *

In Java ME, the platform settings are used for SSL connections.

*

* 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. *

*

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 null.

* * @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 * @param executorService used for managing threads. If null then a newFixedThreadPool 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 65535 characters in length * @throws MqttException if any other problem was encountered */ public MqttClient(String serverURI, String clientId, MqttClientPersistence persistence, ScheduledExecutorService executorService) throws MqttException { aClient = new MqttAsyncClient(serverURI, clientId, persistence, new ScheduledExecutorPingSender(executorService), executorService); } /* * @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#connect(MqttConnectOptions) */ public IMqttToken connectWithResult(MqttConnectOptions options) throws MqttSecurityException, MqttException { IMqttToken tok = aClient.connect(options, null, null); tok.waitForCompletion(getTimeToWait()); return tok; } /* * @see IMqttClient#disconnect() */ public void disconnect() throws MqttException { aClient.disconnect().waitForCompletion(); } /* * @see IMqttClient#disconnect(long) */ public void disconnect(long quiesceTimeout) throws MqttException { aClient.disconnect(quiesceTimeout, null, null).waitForCompletion(); } /* * (non-Javadoc) * * @see org.eclipse.paho.client.mqttv3.IMqttAsyncClient#disconnectForcibly() */ public void disconnectForcibly() throws MqttException { aClient.disconnectForcibly(); } /* * (non-Javadoc) * * @see org.eclipse.paho.client.mqttv3.IMqttAsyncClient#disconnectForcibly(long) */ public void disconnectForcibly(long disconnectTimeout) throws MqttException { aClient.disconnectForcibly(disconnectTimeout); } /* * (non-Javadoc) * * @see org.eclipse.paho.client.mqttv3.IMqttAsyncClient#disconnectForcibly(long, long) */ public void disconnectForcibly(long quiesceTimeout, long disconnectTimeout) throws MqttException { aClient.disconnectForcibly(quiesceTimeout, disconnectTimeout); } /* * @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; iSet the maximum time to wait for an action to complete before * returning control to the invoking application. Control is returned * when: *
    *
  • the action completes *
  • or when the timeout if exceeded *
  • or when the client is disconnect/shutdown *
      * 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. *

      * @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(); } /** * Returns the currently connected Server URI * Implemented due to: https://bugs.eclipse.org/bugs/show_bug.cgi?id=481097 * * Where getServerURI only returns the URI that was provided in * MqttAsyncClient's constructor, getCurrentServerURI returns the URI of the * Server that the client is currently connected to. This would be different in scenarios * where multiple server URIs have been provided to the MqttConnectOptions. * * @return the currently connected server URI */ public String getCurrentServerURI(){ return aClient.getCurrentServerURI(); } /* (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); } /* (non-Javadoc) * @see org.eclipse.paho.client.mqttv3.IMqttClient#setCallback(org.eclipse.paho.client.mqttv3.MqttCallback) */ public void setManualAcks(boolean manualAcks) { aClient.setManualAcks(manualAcks); } public void messageArrivedComplete(int messageId, int qos) throws MqttException { aClient.messageArrivedComplete(messageId, qos); } /** * Returns a randomly generated client identifier based on the current user's login * name and the system time. *

      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.

      * @return a generated client identifier * @see MqttConnectOptions#setCleanSession(boolean) */ public static String generateClientId() { return MqttAsyncClient.generateClientId(); } public void reconnect() throws MqttException { aClient.reconnect(); } /** * Return a debug object that can be used to help solve problems. */ public Debug getDebug() { return (aClient.getDebug()); } }




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