public boolean protocolConnect()

in geronimo-mail_2.1_impl/geronimo-mail_2.1_provider/src/main/java/org/apache/geronimo/mail/store/imap/connection/IMAPConnection.java [108:188]
49 lines of code
13 McCabe index (conditional complexity)

    public boolean protocolConnect(String host, int port, String authid, String realm, String username, String password) throws MessagingException {
        this.serverHost = host;
        this.serverPort = port;
        this.realm = realm;
        this.authid = authid;
        this.username = username;
        this.password = password;

        boolean preAuthorized = false;

        try {
            // create socket and connect to server.
            getConnection();

            // we need to ask the server what its capabilities are.  This can be done
            // before we login.
            getCapability();
            // do a preauthoriziation check.
            if (extractResponse("PREAUTH") != null) {
                preAuthorized = true;
            }

            // make sure we process these now
            processPendingResponses();
            
            boolean requireTLS = props.getBooleanProperty(MAIL_STARTTLS_REQUIRED, false);
            boolean enableTLS = props.getBooleanProperty(MAIL_STARTTLS_ENABLE, false);
            boolean serverSupportsTLS = hasCapability(CAPABILITY_STARTTLS);

            // if we're not already using an SSL connection, and we have permission to issue STARTTLS or its even required
            // try to setup a SSL connection
            if (!sslConnection && (enableTLS || requireTLS)) {
                
                //if the server does not support TLS check if its required.
                //If true then throw an error, if not establish a non SSL connection
                if(requireTLS && !serverSupportsTLS) {
                    throw new MessagingException("Server doesn't support required transport level security");
                } else if (serverSupportsTLS){
                    // tell the server of our intention to start a TLS session
                    sendSimpleCommand("STARTTLS");
    
                    // The connection is then handled by the superclass level.
                    getConnectedTLSSocket();
    
                    // create the special reader for pulling the responses.
                    reader = new IMAPResponseStream(inputStream);
    
                    // the IMAP spec states that the capability response is independent of login state or
                    // user, but I'm not sure I believe that to be the case.  It doesn't hurt to refresh
                    // the information again after establishing a secure connection.
                    getCapability();
                    // and we need to repeat this check.
                    if (extractResponse("PREAUTH") != null) {
                        preAuthorized = true;
                    }
                } else {
                    if (debug) {
                        debugOut("STARTTLS is enabled but not required and server does not support it. So we establish a connection without transport level security");
                    }
                }
                
            }

            // damn, no login required.
            if (preAuthorized) {
                return true;
            }

            // go login with the server
            return login();
        } catch (IOException e) {
            if (debug) {
                debugOut("I/O exception establishing connection", e);
            }
            throw new MessagingException("Connection error", e);
        }
        finally {
            // make sure the queue is cleared
            processPendingResponses();
        }
    }