Split Client#onlineInit method up into performHandshake and initReceiver

src/main/java/envoy/client/net/Client.java

@@ -42,6 +42,7 @@ public class Client implements Closeable {
 	// Asynchronously initialized during handshake
 	private volatile User		sender;
 	private volatile Contacts	contacts;
+	private volatile boolean	rejected;
 
 	// Configuration and logging
 	private static final Config	config	= Config.getInstance();
@@ -54,16 +55,19 @@ public class Client implements Closeable {
 	 * an exception is thrown.
 	 *
 	 * @param credentials          the login credentials of the user
-	 * @param localDb              the local database used to persist the current
-	 *                             {@link IdGenerator}
 	 * @param receivedMessageCache a message cache containing all unread messages
 	 *                             from the server that can be relayed after
 	 *                             initialization
-	 * @throws Exception if the online mode could not be entered or the request
-	 *                   failed for some other reason
-	 * @since Envoy v0.2-alpha
+	 * @throws TimeLimitExceededException if the server could not be reached
+	 * @throws IOException                if the login credentials could not be
+	 *                                    written
+	 * @throws InterruptedException       if the current thread is interrupted while
+	 *                                    waiting for the handshake response
 	 */
-	public void onlineInit(LoginCredentials credentials, LocalDb localDb, Cache<Message> receivedMessageCache) throws Exception {
+	public void performHandshake(LoginCredentials credentials, Cache<Message> receivedMessageCache)
+			throws TimeLimitExceededException, IOException, InterruptedException {
+		if (online) throw new IllegalStateException("Handshake has already been performed successfully");
+
 		// Establish TCP connection
 		logger.info(String.format("Attempting connection to server %s:%d...", config.getServer(), config.getPort()));
 		socket = new Socket(config.getServer(), config.getPort());
@@ -76,7 +80,9 @@ public class Client implements Closeable {
 		receiver.registerProcessor(User.class, sender -> { logger.info("Acquired user object " + sender); this.sender = sender; });
 		receiver.registerProcessor(Contacts.class, contacts -> { logger.info("Acquired contacts object " + contacts); this.contacts = contacts; });
 		receiver.registerProcessor(Message.class, receivedMessageCache);
-		receiver.registerProcessor(HandshakeRejectionEvent.class, EventBus.getInstance()::dispatch);
+		receiver.registerProcessor(HandshakeRejectionEvent.class, evt -> { rejected = true; EventBus.getInstance().dispatch(evt); });
+
+		rejected = false;
 
 		// Start receiver
 		new Thread(receiver).start();
@@ -88,6 +94,15 @@ public class Client implements Closeable {
 		// Wait for a maximum of five seconds to acquire the sender object
 		long start = System.currentTimeMillis();
 		while (sender == null || contacts == null) {
+
+			// Quit immediately after handshake rejection
+			// This method can then be called again
+			if (rejected) {
+				socket.close();
+				receiver.removeAllProcessors();
+				return;
+			}
+
 			if (System.currentTimeMillis() - start > 5000) throw new TimeLimitExceededException("Did not log in after 5 seconds");
 			Thread.sleep(500);
 		}
@@ -97,8 +112,23 @@ public class Client implements Closeable {
 
 		// Remove user creation processor
 		receiver.removeAllProcessors();
+	}
 
-		// Register processors for message and status handling
+	/**
+	 * Initializes the {@link Receiver} used to process data sent from the server to
+	 * this client.
+	 *
+	 * @param localDb              the local database used to persist the current
+	 *                             {@link IdGenerator}
+	 * @param receivedMessageCache a message cache containing all unread messages
+	 *                             from the server that can be relayed after
+	 *                             initialization
+	 * @throws IOException if no {@link IdGenerator} is present and none could be
+	 *                     requested from the server
+	 * @since Envoy v0.2-alpha
+	 */
+	public void initReceiver(LocalDb localDb, Cache<Message> receivedMessageCache) throws IOException {
+		checkOnline();
 
 		// Process incoming messages
 		final ReceivedMessageProcessor receivedMessageProcessor = new ReceivedMessageProcessor();

src/main/java/envoy/client/ui/Startup.java

@@ -62,7 +62,7 @@ public class Startup {
 			if (args.length > 0) config.load(args);
 
 			// Check if all mandatory configuration values have been initialized
-			if (!config.isInitialized()) throw new EnvoyException("Server or port are not defined");
+			if (!config.isInitialized()) throw new EnvoyException("Configuration is not fully initialized");
 		} catch (Exception e) {
 			JOptionPane
 				.showMessageDialog(null, "Error loading configuration values:\n" + e.toString(), "Configuration error", JOptionPane.ERROR_MESSAGE);
@@ -109,7 +109,8 @@ public class Startup {
 		try {
 			// Try entering online mode first
 			localDb.loadIdGenerator();
-			client.onlineInit(credentials, localDb, cache);
+			client.performHandshake(credentials, cache);
+			client.initReceiver(localDb, cache);
 		} catch (Exception e1) {
 			logger.warning("Could not connect to server. Trying offline mode...");
 			e1.printStackTrace();