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Classic word count topology in Storm using 2 RabbitMQ queues

I have to write a simple "Word Count" Topology in Java and Storm. In particular, i have an external data source generating CSV (comma separated) string like
Daniel, 0.5654, 144543, user, 899898, Comment,,,
These strings are inserted into a RabbitMQ queue called "input". This datasource works well, and i can see the strings in the queue.
Now, i modified the classic topology adding the RabbitMQSpout. The goal is to do a word count for the first field of every CSV line, and publish results into a new queue called "output". The problem is that i cannot see any tuple inside the new queue, but the topology was submitted and RUNNING.
So, summing up:
external data source puts items into the input queue
RabbitMQSpout takes items from input queue and insert them into topology
classic word-count topology isperformed
last bolt puts results into output queue
Problem:
i can see items inside input queue, but nothing into output, even if i used same method to send item into the queue in the external data source (and it works) and in RabbitMQExporter (does not work...)
Some code below
RabbitMQSpout
public class RabbitMQSpout extends BaseRichSpout {
public static final String DATA = "data";
private SpoutOutputCollector _collector;
private RabbitMQManager rabbitMQManager;
#Override
public void open(Map map, TopologyContext topologyContext, SpoutOutputCollector spoutOutputCollector) {
_collector = _collector;
rabbitMQManager = new RabbitMQManager("localhost", "rabbitmq", "rabbitmq", "test");
}
#Override
public void nextTuple() {
Utils.sleep(1000);
String data = rabbitMQManager.receive("input");
if (data != null) {
_collector.emit(new Values(data));
}
}
#Override
public void declareOutputFields(OutputFieldsDeclarer outputFieldsDeclarer) {
outputFieldsDeclarer.declare(new Fields(DATA));
}
}
SplitBolt
public class SplitBolt extends BaseRichBolt {
private OutputCollector _collector;
public SplitSentenceBolt() { }
#Override
public void prepare(Map stormConf, TopologyContext context, OutputCollector collector) {
this._collector = collector;
this.SPACE = Pattern.compile(",");
}
#Override
public void execute(Tuple input) {
String sentence = input.getStringByField(RabbitMQSpout.DATA);
String[] words = sentence.split(",");
if (words.length > 0)
_collector.emit(new Values(words[0]));
}
#Override
public void declareOutputFields(OutputFieldsDeclarer declarer) {
declarer.declare(new Fields("word"));
}
#Override
public Map<String, Object> getComponentConfiguration() {
return null;
}
}
WordCountBolt
public class WordCountBolt extends BaseBasicBolt {
Map<String, Integer> counts = new HashMap<String, Integer>();
#Override
public void execute(Tuple tuple, BasicOutputCollector collector) {
String word = tuple.getString(0);
Integer count = counts.get(word);
if (count == null)
count = 0;
count++;
counts.put(word, count);
System.out.println(count);
collector.emit(new Values(word, count));
}
#Override
public void declareOutputFields(OutputFieldsDeclarer declarer) {
declarer.declare(new Fields("word", "count"));
}
}
RabbitMQExporterBolt
public RabbitMQExporterBolt(String rabbitMqHost, String rabbitMqUsername, String rabbitMqPassword,
String defaultQueue) {
super();
this.rabbitMqHost = rabbitMqHost;
this.rabbitMqUsername = rabbitMqUsername;
this.rabbitMqPassword = rabbitMqPassword;
this.defaultQueue = defaultQueue;
}
#Override
public void prepare(#SuppressWarnings("rawtypes") Map map, TopologyContext topologyContext, OutputCollector outputCollector) {
this.collector=outputCollector;
this.rabbitmq = new RabbitMQManager(rabbitMqHost, rabbitMqUsername, rabbitMqPassword, defaultQueue);
}
#Override
public void execute(Tuple tuple) {
String word = tuple.getString(0);
Integer count = tuple.getInteger(1);
String output = word + " " + count;
rabbitmq.send(output);
}
#Override
public void declareOutputFields(OutputFieldsDeclarer outputFieldsDeclarer) {
outputFieldsDeclarer.declare(new Fields("word"));
}
}
Topology
public class WordCountTopology {
private static final String RABBITMQ_HOST = "rabbitmq";
private static final String RABBITMQ_USER = "rabbitmq";
private static final String RABBITMQ_PASS = "rabbitmq";
private static final String RABBITMQ_QUEUE = "output";
public static void main(String[] args) throws Exception {
TopologyBuilder builder = new TopologyBuilder();
builder.setSpout("spout", new RabbitMQSpout(), 1);
builder.setBolt("split", new SplitSentenceBolt(), 1)
.shuffleGrouping("spout");
builder.setBolt("count", new WordCountBolt(), 1)
.fieldsGrouping("split", new Fields("word"));
Config conf = new Config();
conf.setDebug(true);
if (args != null && args.length > 0) {
builder.setBolt("exporter",
new RabbitMQExporterBolt(
RABBITMQ_HOST, RABBITMQ_USER,
RABBITMQ_PASS, RABBITMQ_QUEUE ),
1)
.shuffleGrouping("count");
conf.setNumWorkers(3);
StormSubmitter.submitTopologyWithProgressBar(args[0], conf, builder.createTopology());
} else {
conf.setMaxTaskParallelism(3);
LocalCluster cluster = new LocalCluster();
cluster.submitTopology("word-count", conf, builder.createTopology());
Thread.sleep(10000);
cluster.shutdown();
}
}
}
RabbitMQManager
public class RabbitMQManager {
private String host;
private String username;
private String password;
private ConnectionFactory factory;
private Connection connection;
private String defaultQueue;
public RabbitMQManager(String host, String username, String password, String queue) {
super();
this.host = host;
this.username = username;
this.password = password;
this.factory = null;
this.connection = null;
this.defaultQueue = queue;
this.initialize();
this.initializeQueue(defaultQueue);
}
private void initializeQueue(String queue){
ConnectionFactory factory = new ConnectionFactory();
factory.setHost(host);
factory.setUsername(username);
factory.setPassword(password);
Connection connection;
try {
connection = factory.newConnection();
Channel channel = connection.createChannel();
boolean durable = false;
boolean exclusive = false;
boolean autoDelete = false;
channel.queueDeclare(queue, durable, exclusive, autoDelete, null);
channel.close();
connection.close();
} catch (IOException | TimeoutException e) {
e.printStackTrace();
}
}
private void initialize(){
factory = new ConnectionFactory();
factory.setHost(host);
factory.setUsername(username);
factory.setPassword(password);
try {
connection = factory.newConnection();
} catch (IOException | TimeoutException e) {
e.printStackTrace();
}
}
public void terminate(){
if (connection != null && connection.isOpen()){
try {
connection.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
private boolean reopenConnectionIfNeeded(){
try {
if (connection == null){
connection = factory.newConnection();
return true;
}
if (!connection.isOpen()){
connection = factory.newConnection();
}
} catch (IOException | TimeoutException e) {
e.printStackTrace();
return false;
}
return true;
}
public boolean send(String message){
return this.send(defaultQueue, message);
}
public boolean send(String queue, String message){
try {
reopenConnectionIfNeeded();
Channel channel = connection.createChannel();
channel.basicPublish("", queue, null, message.getBytes());
channel.close();
return true;
} catch (IOException | TimeoutException e) {
e.printStackTrace();
}
return false;
}
public String receive(String queue) {
try {
reopenConnectionIfNeeded();
Channel channel = connection.createChannel();
Consumer consumer = new DefaultConsumer(channel);
return channel.basicConsume(queue, true, consumer);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
}

Publisher MQTT client stops to work in Subscriber's Callback. (PAHO JAVA)

I'm trying to implement a fake broker (actually it is an mqtt publisher client in an mqtt subscriber's callback). There are 3 separated publisher clients which are publishing random numbers between 0 and 1. This fake broker just summarizes this random numbers, and publishes away to an other topic. (Maybe not in the right way, but for now it is ok) This solution is working but after a few incoming messages this broker stops to work. I Tried to debug it, but I found only ClassNotFound Exceptions... Here is my FakeBroker and it's Callback implementation.
public class FakeBroker implements Runnable{
public static final String BROKER_URL = "";
public static final String TOPIC_FAKE_A = "";
public static final String TOPIC_FAKE_B = "";
public static final String TOPIC_FAKE_C = "";
public static final String USER_NAME = "";
public static final char[] USER_PSW = "".toCharArray();
private MqttClient client;
private MqttConnectOptions options;
private SubscriberCallback callback;
public FakeBroker() {
options = new MqttConnectOptions();
options.setUserName(USER_NAME);
options.setPassword(USER_PSW);
options.setCleanSession(false);
callback = new SubscriberCallback();
try {
client = new MqttClient(BROKER_URL, MqttClient.generateClientId()+"-sub");
client.setCallback(callback);
} catch (MqttException e) {
e.printStackTrace();
System.exit(1);
}
}
public void start() {
try {
client.connect(options);
System.out.println("Fake Broker are connected to the cloud.");
client.subscribe(TOPIC_FAKE_A);
client.subscribe(TOPIC_FAKE_B);
client.subscribe(TOPIC_FAKE_C);
} catch (MqttException e) {
e.printStackTrace();
}
}
#Override
public void run() {
start();
}
}
And here is it's Callback
public class SubscriberCallback implements MqttCallback {
public static final String BROKER_URL = "";
public static final String TOPIC_FAKE_BROKER = "";
public static final String USER_NAME = "";
public static final char[] USER_PSW = "".toCharArray();
private MqttClient client;
private MqttConnectOptions options;
private int counter = 1;
private int result = 0;
public SubscriberCallback() {
try {
client = new MqttClient(BROKER_URL, "4-pub");
options = new MqttConnectOptions();
options.setPassword(USER_PSW);
options.setUserName(USER_NAME);
} catch (MqttException e) {
e.printStackTrace();
}
}
#Override
public void connectionLost(Throwable throwable) {
}
#Override
public void messageArrived(String topic, MqttMessage mqttMessage) throws Exception {
System.out.println("Message Arrived. Topic " + topic + " message: " +mqttMessage + " ---- Message Counter: " + counter);
int number = Integer.parseInt(mqttMessage.toString());
result += number;
if (counter%3 == 0) {
publishAway(new MqttMessage(Integer.toString(result).getBytes()));
result = 0;
}
incrementCounter();
}
private void publishAway(MqttMessage mqttMessage) throws MqttException {
client.connect(options);
final MqttTopic topicFakeBroker = client.getTopic(TOPIC_FAKE_BROKER);
topicFakeBroker.publish(mqttMessage);
client.disconnect();
System.out.println("Fake broker got the message " + mqttMessage + " and published away to" + topicFakeBroker.getName());
}
#Override
public void deliveryComplete(IMqttDeliveryToken iMqttDeliveryToken) {
}
private void incrementCounter() {
counter++;
}
}
Of course I use valid BROKER_URL and TOPICS but these informations are confidential. Thanks for Your answers! :)

java cometD + selenium. Client communication not stable

My scheme: ajax long polling to Tomcat. Tomcat executes selenium "operations".
Im trying to execute selenium scenario from tomcat.
Its working ok but i need to get logs back to js client.
Javascript client partially receives messages from server when selenium working.
Inside some selenium operations im using Thread.sleep(). Maybe mistakes because of this ?
Please tell me why messages partially received (i think) by client
Here is ServerInfoLogger. BaseLogger outputs messages to console and file
public class ServerInfoLogger extends BaseLogger {
public ServerSession clientServerSession;
protected void logToClient(String message) {
super.log(message);
sendMessage(message);
}
// Server.serverSession and Server.clientServerSession not null but messages partially not received by client
private void sendMessage(String message) {
// send message to client
if (Server.serverSession!=null && Server.clientServerSession!=null) {
Server.clientServerSession.deliver(Server.serverSession, "/message", message);
} else {
System.err.println("Server error. Server.serverSession=" + Server.serverSession + " clientServerSession=" + clientServerSession);
}
}
}
Here is selenium scenario
public class Task extends ServerInfoLogger {
public static boolean datesAvailable = false;
private TaskParser parser = new TaskParser();
protected ArrayList<Step> steps = new ArrayList<>();
private WebDriver webDriver;
protected int currentStepIndex = 0;
protected Step currentStep;
private WebDriverFactory webDriverFactory = new WebDriverFactory();
private int currentTryout = 1;
private int maxTryouts = 40;
public Task(ServerSession clientServerSession, String taskData) {
this.clientServerSession = clientServerSession;
logToClient("new task"); // client always receives this message
steps = parser.parse(taskData);
logToClient("steps parsed. total: "+steps.size()); // client always receives this message
start();
}
protected void start() {
createWebDriver();
startStep();
}
protected void startStep() {
currentStep = steps.get(currentStepIndex);
currentStep.setWebDriver(webDriver);
currentStep.clientServerSession = clientServerSession;
boolean stepComplete = false;
try {
stepComplete = currentStep.start();
} catch (StepException e) {
logToClient(e.getMessage()+" step id: "+e.getStepId());
e.printStackTrace();
}
log("step complete = "+stepComplete);
if (stepComplete) {
onStepComplete();
} else {
onStepError();
}
}
private void onStepError() {
currentTryout++;
if (currentTryout > maxTryouts) {
destroyWebDriver();
logToClient("Max tryouts reached"); // client never receives this message
} else {
logToClient("Step not complete. Restarting task. currentTryout=" + currentTryout); // client partially receives this message
restart();
}
}
private void onStepComplete() {
currentStepIndex++;
if (currentStepIndex < steps.size()) {
startStep();
} else {
destroyWebDriver();
taskComplete();
}
}
private void destroyWebDriver() {
webDriver.quit();
webDriver = null;
}
private void taskComplete() {
logToClient("Task complete !!!"); // client **never** receives this message
TaskEvent taskEvent = new TaskEvent(TaskEvent.TASK_COMPLETE);
EventDispatcher.getInstance().dispatchEvent(taskEvent);
}
public void restart() {
logToClient("Task restart");
try {
setTimeout(Application.baseOperationWaitSecondsUntil);
new SwitchToDefaultContentOperation().execute();
} catch(OperationException exception) {
logToClient("Cannot get default content"); // client partially receives this message
}
currentStepIndex = 0;
startStep();
}
private void setTimeout(int seconds) {
webDriver.manage().timeouts().implicitlyWait(seconds, TimeUnit.SECONDS);
}
private void createWebDriver() {
webDriver = webDriverFactory.getDriver(BrowserType.CHROME).getDriver();
}
public int getCurrentStepIndex() {
return currentStepIndex;
}
}
Here is creation of logger
private void createLogger() {
Date currentDate = new Date();
String logFilePostfix = currentDate.getMonth()+"_"+currentDate.getDate()+"-"+currentDate.getHours()+"_"+currentDate.getMinutes()+"_"+currentDate.getSeconds();
logger = Logger.getLogger(appName);
logger.setUseParentHandlers(false);
FileHandler fh;
SimplestFormatter formatter = new SimplestFormatter();
try {
fh = new FileHandler("C:\\consultant\\logs\\log_"+logFilePostfix+".txt");
logger.addHandler(fh);
fh.setFormatter(formatter);
} catch (SecurityException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
Selenium operation with Thread.sleep()
public class SwitchToMainFrameOperation extends BaseOperation {
private WebElement mainIframe;
private WebDriverWait wait;
#Override
public boolean execute() throws OperationException {
switchToRoot();
sleepThread();
log("switchToMainIFrame by xPath "+Page.getMainIframeXPath()); // log to console and file
wait = new WebDriverWait(webDriver, Application.baseOperationWaitSecondsUntil);
try {
mainIframe = wait.until(ExpectedConditions.presenceOfElementLocated(By.xpath(Page.getMainIframeXPath())));
webDriver.switchTo().frame(mainIframe);
log("main frame switch OK"); // log to console and file
} catch(StaleElementReferenceException exception) {
log("main frame switch error. StaleElementReferenceException - trying again"); // log to console and file
wait = null;
sleepThread();
execute();
}
return true;
}
private void switchToRoot() {
log("switch to root");
webDriver.switchTo().defaultContent();
}
private void sleepThread() {
try {
Thread.sleep(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}

How to call the websocket server to sends the message to the client in spring

My project uses spring framework
WebSocketConfig.java
#Configuration
#EnableWebMvc
#EnableWebSocket
public class WebSocketConfig extends WebMvcConfigurerAdapter implements WebSocketConfigurer {
#Override
public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
registry.addHandler(systemWebSocketHandler(),"/webSocketServer").addInterceptors(new WebSocketHandshakeInterceptor());
registry.addHandler(systemWebSocketHandler(), "/sockjs/webSocketServer").addInterceptors(new WebSocketHandshakeInterceptor())
.withSockJS();
}
#Bean
public WebSocketHandler systemWebSocketHandler(){
return new SystemWebSocketHandler();
}
}
SystemWebSocketHandler.java
public class SystemWebSocketHandler implements WebSocketHandler {
private static final Logger logger;
private static final ArrayList<WebSocketSession> users;
static {
users = new ArrayList<>();
logger = LoggerFactory.getLogger(SystemWebSocketHandler.class);
}
#Autowired
private WebSocketService webSocketService;
#Override
public void afterConnectionEstablished(WebSocketSession session) throws Exception {
logger.debug("connect to the websocket success......");
users.add(session);
String userName = (String) session.getAttributes().get(Constants.WEBSOCKET_USERNAME);
//查询未读消息
int count = webSocketService.getUnReadNews((String)session.getAttributes().get(Constants.WEBSOCKET_USERNAME));
session.sendMessage(new TextMessage(count+""));
}
#Override
public void handleMessage(WebSocketSession session, WebSocketMessage<?> message) throws Exception {
}
#Override
public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception {
logger.debug("websocket connection closed......");
users.remove(session);
}
#Override
public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception {
logger.debug("websocket connection closed......");
users.remove(session);
}
#Override
public boolean supportsPartialMessages() {
return false;
}
/**
* 给所有在线用户发送消息
*
* #param message
*/
public void sendMessageToUsers(TextMessage message) {
for (WebSocketSession user : users) {
try {
if (user.isOpen()) {
user.sendMessage(message);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* 给某个用户发送消息
*
* #param userName
* #param message
*/
public void sendMessageToUser(String userName, TextMessage message) {
for (WebSocketSession user : users) {
if (user.getAttributes().get(Constants.WEBSOCKET_USERNAME).equals(userName)) {
try {
if (user.isOpen()) {
user.sendMessage(message);
}
} catch (IOException e) {
e.printStackTrace();
}
break;
}
}
}
}
my jsp client
if ('WebSocket' in window) {
websocket = new WebSocket("ws://localhost:8080/Origami/webSocketServer");
} else if ('MozWebSocket' in window) {
websocket = new MozWebSocket("ws://localhost:8080/Origami/webSocketServer");
} else {
websocket = new SockJS("http://localhost:8080/Origami/sockjs/webSocketServer");
}
this is my websocket code and it works well
now I want to send messages to the client in a controller ,this is my controller
#Controller
public class AdminController {
static Logger logger = LoggerFactory.getLogger(AdminController.class);
#Autowired(required = false)
private AdminService adminService;
#Autowired(required = false)
private SystemWebSocketHandler systemWebSocketHandler;
#RequestMapping("/auditing")
#ResponseBody
public String auditing(HttpServletRequest request){
String result = "fail";
int id = Integer.parseInt(request.getParameter("id"));
String reason = request.getParameter("reason");
String title = request.getParameter("title");
String username = request.getParameter("username");
News news = new News();
DateTime dateTime = DateTime.now();
news.setNewsTime(dateTime.toDate());
news.setState(0);
news.setUsername(username);
if(reason.equals("")){
result = adminService.auditingById(id,"Y");
news.setNewsContent(String.format(Constants.AUDIT_MESSAGE, username, title, reason));
adminService.addNewsWithUnAudit(news);
}else{
news.setNewsContent(String.format(Constants.UN_AUDIT_MESSAGE,username,title,reason));
result = adminService.addNewsWithUnAudit(news);
result = adminService.auditingById(id, "D");
}
//SystemServerEndPoint serverEndPoint = new SystemServerEndPoint();
int unReadNewsCount = adminService.getUnReadNews(username);
systemWebSocketHandler.sendMessageToUser(username, new TextMessage(unReadNewsCount + ""));
return result;
}
}
I want to call
systemWebSocketHandler.sendMessageToUser(username, new TextMessage(unReadNewsCount + ""));
to send message to the client but systemWebSocketHandler is null
How to inject the systemWebSocketHandler to the controller
or some other ideas to complete the required? Such as the server connect to the websocketserver when it need to send message to the client and closed when it finished
My English is poor, but I'm trying to learn

I have resolved the problem
#Controller
public class AdminController {
#Bean
public SystemWebSocketHandler systemWebSocketHandler() {
return new SystemWebSocketHandler();
}

Detecting user inactivity in a desktop application

I have an application in Eclipse RCP where I want to fire a function called 'LogOutUser()' if the user leaves his/ her application idle for, say, five minutes.
How do I go about doing this?

I don't know if the RCP framework supports this internally. However, I wrote my own "helper" class, which is a singleton client session manager. Eclipse won't know natively how you connect to your datasource. In my case I am connecting using EJB3 calls and listening to JMS queues and topics.
My class was written to detect when the datasource or "server" went down. It would also reconnect when the server came up. The server inactivity is detected by listening to heartbeat DTO's sent by the server. This feedback is useful to present to the user. I have adapted this class to cater for user interface inactivity.
The class is quite simple. It is a singleton, so it can be called simply at any point in your client-side RCP application. The heartbeat uses an observer and so you will have to add a HeartBeatEventListener to hook into this functionality. You can adapt the class to do the same for the user interface inactivity. However, I have just provided an updateUserInterfaceActivity() method which you must call when there is user activity. Perhaps this can be hooked into a global mouse and a global keyboard event handler.
I have also added a TrayItem to update the user...
Here is the class:
package com.kingsleywebb.clientsessionmanagement;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.MenuItem;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.ToolTip;
import org.eclipse.swt.widgets.TrayItem;
import com.kingsleywebb.clientsessionmanagement.entity.HeartbeatDTO;
public class ClientSessionManagement implements HeartbeatEventListener {
private static final Image IMG_CONNECTED = null; // Set this to a "connected image"
private static final Image IMG_DISCONNECTED = null; // Set this to a "disconnected image"
private static final long CONNECTION_INACTIVITY_TIME_MS = 30000L; // 30 seconds
private static final long USER_INTERFACE_INACTIVITY_TIME_MS = 300000L; // 5 minutes
private static final Log LOG = LogFactory.getLog(ClientSessionManagement.class);
private static ClientSessionManagement theInstance = null;
private static long connectionTimestamp = 0;
private static long userInterfaceActivityTimestamp = 0;
private synchronized static void createInstance() {
if (theInstance == null) {
theInstance = new ClientSessionManagement();
}
}
public static ClientSessionManagement getInstance() {
if (theInstance == null) {
createInstance();
}
return theInstance;
}
private ClientSessionManagement() {
this.connectionListenerList = new ArrayList<ConnectionListener>();
updateConnectionTimestamp();
Cron cron = new Cron();
Thread cronThread = new Thread(cron);
cronThread.start();
}
private boolean connected = true;
private ToolTip toolTipConnected;
private ToolTip toolTipDisconnected;
private TrayItem trayItem = null;
private String appName = null;
private String version = null;
private String whiteLabel = null;
private String userName = null;
private String deskName = null;
private String serverName = null;
private String userMnemonic = null;
private MenuItem miShowPopups;
private MenuItem miSoundBeep;
private List<ConnectionListener> connectionListenerList;
private void updateConnectionTimestamp() {
ClientSessionManagement.connectionTimestamp = System.currentTimeMillis();
}
private synchronized long getLastHeartbeatInMsAgo() {
return System.currentTimeMillis() - ClientSessionManagement.connectionTimestamp;
}
public synchronized void updateHeartbeat() {
updateConnectionTimestamp();
}
public synchronized void checkHeartbeatInterval() {
if (getLastHeartbeatInMsAgo() < CONNECTION_INACTIVITY_TIME_MS) {
showConnected();
}
else {
showDisconnected();
}
}
private void updateUserInterfaceActivityTimestamp() {
ClientSessionManagement.userInterfaceActivityTimestamp = System.currentTimeMillis();
}
private synchronized long getLastUserInterfaceActivityInMsAgo() {
return System.currentTimeMillis() - ClientSessionManagement.userInterfaceActivityTimestamp;
}
public synchronized void updateUserInterfaceActivity() {
updateUserInterfaceActivityTimestamp();
}
public synchronized void checkUserInterfaceActivityInterval() {
if (getLastUserInterfaceActivityInMsAgo() > USER_INTERFACE_INACTIVITY_TIME_MS) {
logoutUser();
}
}
private void logoutUser() {
// Implement logout functionality here
}
private void showConnected() {
if (!connected) {
connected = true;
Display.getDefault().asyncExec(new Runnable() {
public void run() {
// Update icon
if (trayItem != null) {
trayItem.setImage(ClientSessionManagement.IMG_CONNECTED);
trayItem.getToolTip().setVisible(false);
trayItem.setToolTip(toolTipConnected);
trayItem.getToolTip().setVisible(true);
}
// Update hover tooltip
updateHoverTooltip();
}
});
notifyConnectionListeners();
}
}
private void showDisconnected() {
if (connected) {
connected = false;
Display.getDefault().asyncExec(new Runnable() {
public void run() {
// Update icon
if (trayItem != null) {
trayItem.setImage(ClientSessionManagement.IMG_DISCONNECTED);
trayItem.getToolTip().setVisible(false);
trayItem.setToolTip(toolTipDisconnected);
trayItem.getToolTip().setVisible(true);
}
// Update hover tooltip
updateHoverTooltip();
}
});
notifyConnectionListeners();
}
}
private void updateHoverTooltip() {
if (trayItem != null) {
// Application info
String applicationInfo = null;
if (appName != null && version != null && whiteLabel != null) {
// appName* | version | whitelabel
applicationInfo = " Application: " + " " + appName + " " + version + " [" + whiteLabel + "]\r\n";
}
// User info
String userInfo = null;
if (userName != null && deskName != null && serverName != null) {
userInfo = " User: " + " " + userName + " (" + deskName + ") on " + serverName + "\r\n";
}
// Connection info
String connectionInfo = connected ? " Server Connected" : " SERVER DISCONNECTED!!!";
String status = connectionInfo + "\r\n\r\n" + (applicationInfo != null ? applicationInfo : "") +
(userInfo != null ? userInfo : "");
trayItem.setToolTipText(status);
LOG.info(status);
}
}
public void setTrayItem(Shell shell, TrayItem trayItem) {
this.trayItem = trayItem;
/*
* Property files to persist these settings - removed for simplicity
*
* final WorkstationProperties p = WorkstationProperties.getInstance();
* boolean showNotificationPopups = !"No".equalsIgnoreCase(p.getProperty("notifications.showNotificationPopups"));
* boolean soundNotificationBeep = !"No".equalsIgnoreCase(p.getProperty("notifications.soundNotificationBeep"));
*/
boolean showNotificationPopups = true;
boolean soundNotificationBeep = true;
final Menu menu = new Menu (shell, SWT.POP_UP);
miShowPopups = new MenuItem (menu, SWT.CHECK);
miShowPopups.setSelection(showNotificationPopups);
miShowPopups.setText("Show Notification Popups");
miShowPopups.addListener (SWT.Selection, new Listener () {
public void handleEvent (Event event) {
LOG.info("notifications.showNotificationPopups = " + miShowPopups.getSelection());
// Property files to persist these settings - removed for simplicity
//p.setProperty("notifications.showNotificationPopups", miShowPopups.getSelection() ? "Yes" : "No");
}
});
miSoundBeep = new MenuItem (menu, SWT.CHECK);
miSoundBeep.setSelection(soundNotificationBeep);
miSoundBeep.setText("Play Notification Beep");
miSoundBeep.addListener (SWT.Selection, new Listener () {
public void handleEvent (Event event) {
LOG.info("notifications.soundNotificationBeep = " + miSoundBeep.getSelection());
// Property files to persist these settings - removed for simplicity
//p.setProperty("notifications.soundNotificationBeep", miSoundBeep.getSelection() ? "Yes" : "No");
}
});
this.trayItem.addListener (SWT.MenuDetect, new Listener () {
public void handleEvent (Event event) {
menu.setVisible (true);
}
});
toolTipConnected = new ToolTip(shell, SWT.BALLOON);
toolTipConnected.setText((appName != null ? appName : "<Application Name>") + " Status");
toolTipConnected.setMessage("Connected to server.");
toolTipConnected.setLocation(600, 600);
toolTipConnected.setVisible(false);
toolTipDisconnected = new ToolTip(shell, SWT.ICON_WARNING);
toolTipDisconnected.setText((appName != null ? appName : "<Application Name>") + " Status");
toolTipDisconnected.setMessage("DISCONNECTED from server.");
toolTipDisconnected.setLocation(500, 500);
toolTipDisconnected.setVisible(false);
this.trayItem.setToolTip(toolTipConnected);
}
public boolean isShowPopups() {
return miShowPopups.getSelection();
}
public boolean isSoundBeep() {
return miSoundBeep.getSelection();
}
public void setAppName(String appName) {
this.appName = appName;
}
public void setVersion(String version) {
this.version = version;
}
public void setWhiteLabel(String whiteLabel) {
this.whiteLabel = whiteLabel;
}
public void setUserName(String userName) {
this.userName = userName;
}
public void setDeskName(String deskName) {
this.deskName = deskName;
}
public void setServerName(String serverName) {
this.serverName = serverName;
updateHoverTooltip();
}
public String getUserMnemonic() {
return userMnemonic;
}
public void setUserMnemonic(String userMnemonic) {
this.userMnemonic = userMnemonic;
}
public void heartbeatArrived(HeartbeatDTO heartbeatDTO) {
updateHeartbeat();
}
public boolean isConnected() {
return connected;
}
public boolean addConnectionListener(ConnectionListener connectionListener) {
return connectionListenerList.add(connectionListener);
}
public boolean removeConnectionListener(ConnectionListener connectionListener) {
return connectionListenerList.remove(connectionListener);
}
public void notifyConnectionListeners() {
for (Iterator<ConnectionListener> i = connectionListenerList.iterator(); i.hasNext();) {
ConnectionListener connectionListener = i.next();
if (connected) {
connectionListener.connected();
}
else {
connectionListener.disconnected();
}
}
}
/**
*
* #author Kingsley Webb
*
* Check heartbeat interval periodically display warning to user accordingly.
*/
class Cron implements Runnable {
public void run() {
// Wait 15s extra before 1st check
try {
Thread.sleep(15000);
} catch (InterruptedException e) {
LOG.error(e);
}
while (true) {
// Check every 5s - increase for better performance, but you get the idea...
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
LOG.error(e);
}
checkHeartbeatInterval();
checkUserInterfaceActivityInterval();
}
}
}
}
Some other supporting classes:
package com.kingsleywebb.clientsessionmanagement;
public interface ConnectionListener {
public void connected();
public void disconnected();
}
package com.kingsleywebb.clientsessionmanagement;
import com.kingsleywebb.clientsessionmanagement.entity.HeartbeatDTO;
public interface HeartbeatEventListener {
public void heartbeatArrived(HeartbeatDTO heartbeatDTO);
}

If you take a look in the bundle org.eclipse.ui.ide.application there is a class org.eclipse.ui.internal.ide.application.IDEIdleHelper which tries to perform gc after a interval of user inactivity. Probably you can reuse the logic that detects the inactivity

I usually use a Display.addFilter(eventType, listener) for the event types that should keep the session alive combined with a Display.timerExec(milliseconds, runnable) that is run periodically and tests for the last interesting event.
I use milliseconds = 5000 so the period is 5 min up to 5 min 5 sec before the user is logged out (or whatever...). Also I listener for the SWT event types (in 3.7) KeyDown, KeyUp, MouseDown, MouseUp, MouseVerticalWheel, MouseHorizontalWheel MouseDoubleClick, Touch, Gesture, Activate, Iconify, Deiconify, Move, and Resize.