Add help texts and update README

README.md

@@ -0,0 +1,8 @@
+# GSoC 2017 - Jingle File Transfer Demo App
+File synchronisation via XMPP.
+
+xmpp_sync has two modes: Master and Slave mode. A client started in master mode will send files 
+out, while clients in slave mode will receive files.
+
+In order to use the program, you need at least two XMPP accounts (which might be on different 
+servers). I recommend using a server, which supports Socks5 proxies.

src/main/java/de/vanitasvitae/sync_client/Client.java

@@ -11,12 +11,10 @@ import java.security.NoSuchAlgorithmException;
 import java.security.NoSuchProviderException;
 import java.util.HashSet;
 import java.util.Set;
-
 import javax.crypto.BadPaddingException;
 import javax.crypto.IllegalBlockSizeException;
 import javax.crypto.NoSuchPaddingException;
 
-import org.jivesoftware.smack.SmackConfiguration;
 import org.jivesoftware.smack.SmackException;
 import org.jivesoftware.smack.XMPPConnection;
 import org.jivesoftware.smack.XMPPException;

src/main/java/de/vanitasvitae/sync_client/Main.java

@@ -46,11 +46,13 @@ public class Main {
         Option debug = Option.builder("d").longOpt("debug").desc("Start in debug mode").build();
         Option directory = Option.builder("D").longOpt("directory").hasArg().required().desc("Directory to sync").build();
         Option master = Option.builder("m").longOpt("master").desc("Start in master mode").build();
+        Option help = Option.builder("h").longOpt("help").desc("Display this help text").build();
         options.addOption(username);
         options.addOption(password);
         options.addOption(debug);
         options.addOption(directory);
         options.addOption(master);
+        options.addOption(help);
         return options;
     }
 
@@ -82,6 +84,11 @@ public class Main {
             return;
         }
 
+        if (cmd.hasOption('h')) {
+            formatter.printHelp("client", options, true);
+            return;
+        }
+
         String username = cmd.getOptionValue('u');
         String password = cmd.getOptionValue('p');
         String dir = cmd.getOptionValue('D');
@@ -212,6 +219,15 @@ public class Main {
                     }
                     break;
 
+                case "/help":
+                    System.out.println("Available commands: \n" +
+                            "/add <user@server.tld>: Add user to roster, or display current roster.\n" +
+                            "/sync <user@server.tld>: Add a users device to synced devices or display currently synced devices.\n" +
+                            "/trust user@sever.tld: Trust a users OMEMO identities.\n" +
+                            "/help: Show this help text.\n" +
+                            "/quit: Quit the application.");
+                    break;
+
                 case "/quit":
                     ((AbstractXMPPConnection) client.connection).disconnect(new Presence(Presence.Type.unavailable, "Shutdown", 100, Presence.Mode.away));
                     break outerloop;