1 /*

     2  * Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies). 

     3  * All rights reserved.

     4  * This component and the accompanying materials are made available

     5  * under the terms of "Eclipse Public License v1.0"

     6  * which accompanies this distribution, and is available

     7  * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8  *

     9  * Initial Contributors:

    10  * Nokia Corporation - initial contribution.

    11  *

    12  * Contributors:

    13  *

    14  * Description:

    15  *

    16  */

    17 

    18 package com.nokia.traceviewer.internal.api;

    19 

    20 import java.util.Collections;

    21 import java.util.HashSet;

    22 import java.util.Iterator;

    23 import java.util.Set;

    24 

    25 import com.nokia.carbide.remoteconnections.interfaces.IConnection;

    26 import com.nokia.traceviewer.api.ITraceConnClient;

    27 import com.nokia.traceviewer.api.ITraceConnInfo;

    28 import com.nokia.traceviewer.api.TraceConnectivityException;

    29 import com.nokia.traceviewer.api.TraceViewerAPI;

    30 import com.nokia.traceviewer.api.TraceViewerAPI2;

    31 import com.nokia.traceviewer.api.TraceViewerAPI.TVAPIError;

    32 import com.nokia.traceviewer.engine.ConnectionHelper;

    33 

    34 /**

    35  * Implementation if TraceViewer API functions that offers - notification

    36  * services for client on connection status changes. - keeps count of active

    37  * clients, and disconnects data source only when there is no more active

    38  * clients.

    39  */

    40 public class TraceViewerAPI2Impl {

    41 

    42 	/**

    43 	 * Storage for currently registered clients.

    44 	 */

    45 	public static Set<ITraceConnClient> clients = Collections

    46 			.synchronizedSet(new HashSet<ITraceConnClient>());

    47 

    48 	/**

    49 	 * Connect using current settings defined in TraceViewer's preferences.

    50 	 * Client is registered successfully in case no exceptions are thrown.

    51 	 * 

    52 	 * @param client

    53 	 *            client requesting the connection.

    54 	 * @return connection info about the connected service.

    55 	 * @throws TraceConnectivityException

    56 	 */

    57 	public static ITraceConnInfo connect(ITraceConnClient client)

    58 			throws TraceConnectivityException {

    59 		TVAPIError error = TraceViewerAPI.connect();

    60 		if (error == TVAPIError.NONE || error == TVAPIError.ALREADY_CONNECTED) {

    61 			// Register must have after connect attempt because it triggers

    62 			// notifications to already registered clients

    63 			registerClient(client);

    64 		} else {

    65 			throw new TraceConnectivityException(error);

    66 		}

    67 		IConnection connectionWithCurrentID = ConnectionHelper

    68 				.getConnectionWithCurrentID();

    69 		return new TraceConnInfo(connectionWithCurrentID);

    70 	}

    71 

    72 	/**

    73 	 * Connects using current settings defined in TraceViewer's preferences

    74 	 * Client is disconnected and unregistered successfully for notifications in

    75 	 * case no exceptions are thrown.

    76 	 * 

    77 	 * @param client

    78 	 *            client requesting the connection.

    79 	 * @throws TraceConnectivityException

    80 	 */

    81 	public static void disconnect(ITraceConnClient client)

    82 			throws TraceConnectivityException {

    83 		// Client is unregistered in any case and must be done before

    84 		// disconnect() is called

    85 		// because ínside disconnect() there is callback back to

    86 		// hasRegisteredClients() method.

    87 		boolean clientWasRegistered = unregisterClient(client);

    88 		// Real disconnect only, if there are no more other clients using the

    89 		// connection

    90 		if (!hasRegisteredClients()) {

    91 			TVAPIError error = TraceViewerAPI.disconnect();

    92 			if (error != TVAPIError.NONE) {

    93 				throw new TraceConnectivityException(error);

    94 			}

    95 		}

    96 		// clientWasRegistered is true if the client was registered before

    97 		// unregister attempt

    98 		if (!clientWasRegistered) {

    99 			// Reporting also possible failures that are possible errors in

   100 			// client code

   101 			throw new RuntimeException(

   102 					TraceViewerAPI2.class.getSimpleName()

   103 							+ ": " //$NON-NLS-1$ 

   104 							+ Messages.TraceViewerAPI2Impl_UnregisterNotRegisteredClient_ErrMsg

   105 							+ ": " + client); //$NON-NLS-1$ 

   106 		}

   107 	}

   108 

   109 	/**

   110 	 * Checks if there are any registered clients left.

   111 	 * 

   112 	 * @return <code>true</code> if there are registered clients, otherwise

   113 	 *         <code>false</code>.

   114 	 */

   115 	public static boolean hasRegisteredClients() {

   116 		synchronized (clients) {

   117 			return !clients.isEmpty();

   118 		}

   119 	}

   120 

   121 	/**

   122 	 * Registers client.

   123 	 * 

   124 	 * @param client

   125 	 *            client to register

   126 	 */

   127 	private static void registerClient(ITraceConnClient client) {

   128 		synchronized (clients) {

   129 			clients.add(client);

   130 		}

   131 	}

   132 

   133 	/**

   134 	 * Unregisters client.

   135 	 * 

   136 	 * @param client

   137 	 *            client to unregister

   138 	 * @return true if the previously registered client was unregistered

   139 	 *         successfully

   140 	 */

   141 	private static boolean unregisterClient(ITraceConnClient client) {

   142 		synchronized (clients) {

   143 			// remove returns true if the set contained the specified element.

   144 			return clients.remove(client);

   145 		}

   146 	}

   147 

   148 	/**

   149 	 * Notifies all client about disconnect event

   150 	 * 

   151 	 * @param currentConnection

   152 	 *            currently selected connection

   153 	 */

   154 	public static void notifyConnection(IConnection currentConnection) {

   155 		synchronized (clients) {

   156 			for (Iterator<ITraceConnClient> iterator = clients.iterator(); iterator

   157 					.hasNext();) {

   158 				ITraceConnClient client = iterator.next();

   159 				client.notifyConnection(new TraceConnInfo(currentConnection));

   160 			}

   161 		}

   162 	}

   163 

   164 	/**

   165 	 * Notifies all client about disconnect event

   166 	 */

   167 	public static void notifyDisconnection() {

   168 		synchronized (clients) {

   169 			for (Iterator<ITraceConnClient> iterator = clients.iterator(); iterator

   170 					.hasNext();) {

   171 				ITraceConnClient client = iterator.next();

   172 				client.notifyDisconnection();

   173 			}

   174 		}

   175 	}

   176 

   177 	/**

   178 	 * Notifies listeners that connection preferences has been changed.

   179 	 * 

   180 	 * @param connectionInfo

   181 	 *            Connection info about the new connection preferences.

   182 	 */

   183 	public static void notifyConnPrefsChanged(IConnection connectionInfo) {

   184 		synchronized (clients) {

   185 			for (Iterator<ITraceConnClient> iterator = clients.iterator(); iterator

   186 					.hasNext();) {

   187 				ITraceConnClient client = iterator.next();

   188 				client

   189 						.notifyConnPrefsChanged(new TraceConnInfo(

   190 								connectionInfo));

   191 			}

   192 		}

   193 	}

   194 

   195 	/**

   196 	 * Gets count of currently registered clients. This method is meant only for

   197 	 * unit testing purposes.

   198 	 * 

   199 	 * @return count of currently registered clients

   200 	 */

   201 	public static int getRegisteredClientsCount() {

   202 		synchronized (clients) {

   203 			return clients.size();

   204 		}

   205 	}

   206 

   207 }