    001: /**
    002:    Connects a phone to the mail system. The purpose of this
    003:    class is to keep track of the state of a connection, since
    004:    the phone itself is just a source of individual key presses.
    005: */
    006: public class Connection
    007: {
    008:    /**
    009:       Construct a Connection object.
    010:       @param s a MailSystem object
    011:       @param p a Telephone object
    012:    */
    013:    public Connection(MailSystem s, Telephone p)
    014:    {
    015:       system = s;
    016:       phone = p;
    017:       resetConnection();
    018:    }
    019:
    020:    /**
    021:       Respond to the user's pressing a key on the phone touchpad
    022:       @param key the phone key pressed by the user
    023:    */
    024:    public void dial(String key)
    025:    {
    026:       if (state == CONNECTED)
    027:          connect(key);
    028:       else if (state == RECORDING)
    029:          login(key);
    030:       else if (state == CHANGE_PASSCODE)
    031:          changePasscode(key);
    032:       else if (state == CHANGE_GREETING)
    033:          changeGreeting(key);
    034:       else if (state == MAILBOX_MENU)
    035:          mailboxMenu(key);
    036:       else if (state == MESSAGE_MENU)
    037:          messageMenu(key);
    038:    }
    039:
    040:    /**
    041:       Record voice.
    042:       @param voice voice spoken by the user
    043:    */
    044:    public void record(String voice)
    045:    {
    046:       if (state == RECORDING || state == CHANGE_GREETING)
    047:          currentRecording += voice;
    048:    }
    049:
    050:    /**
    051:       The user hangs up the phone.
    052:    */
    053:    public void hangup()
    054:    {
    055:       if (state == RECORDING)
    056:          currentMailbox.addMessage(new Message(currentRecording));
    057:       resetConnection();
    058:    }
    059:
    060:    /**
    061:       Reset the connection to the initial state and prompt
    062:       for mailbox number
    063:    */
    064:    private void resetConnection()
    065:    {
    066:       currentRecording = "";
    067:       accumulatedKeys = "";
    068:       state = CONNECTED;
    069:       phone.speak(INITIAL_PROMPT);
    070:    }
    071:
    072:    /**
    073:       Try to connect the user with the specified mailbox.
    074:       @param key the phone key pressed by the user
    075:    */
    076:    private void connect(String key)
    077:    {
    078:       if (key.equals("#"))
    079:       {
    080:          currentMailbox = system.findMailbox(accumulatedKeys);
    081:          if (currentMailbox != null)
    082:          {
    083:             state = RECORDING;
    084:             phone.speak(currentMailbox.getGreeting());
    085:          }
    086:          else
    087:             phone.speak("Incorrect mailbox number. Try again!");
    088:          accumulatedKeys = "";
    089:       }
    090:       else
    091:          accumulatedKeys += key;
    092:    }
    093:
    094:    /**
    095:       Try to log in the user.
    096:       @param key the phone key pressed by the user
    097:    */
    098:    private void login(String key)
    099:    {
    100:       if (key.equals("#"))
    101:       {
    102:          if (currentMailbox.checkPasscode(accumulatedKeys))
    103:          {
    104:             state = MAILBOX_MENU;
    105:             phone.speak(MAILBOX_MENU_TEXT);
    106:          }
    107:          else
    108:             phone.speak("Incorrect passcode. Try again!");
    109:          accumulatedKeys = "";
    110:       }
    111:       else
    112:          accumulatedKeys += key;
    113:    }
    114:
    115:    /**
    116:       Change passcode.
    117:       @param key the phone key pressed by the user
    118:    */
    119:    private void changePasscode(String key)
    120:    {
    121:       if (key.equals("#"))
    122:       {
    123:          currentMailbox.setPasscode(accumulatedKeys);
    124:          state = MAILBOX_MENU;
    125:          phone.speak(MAILBOX_MENU_TEXT);
    126:          accumulatedKeys = "";
    127:       }
    128:       else
    129:          accumulatedKeys += key;
    130:    }
    131:
    132:    /**
    133:       Change greeting.
    134:       @param key the phone key pressed by the user
    135:    */
    136:    private void changeGreeting(String key)
    137:    {
    138:       if (key.equals("#"))
    139:       {
    140:          currentMailbox.setGreeting(currentRecording);
    141:          currentRecording = "";
    142:          state = MAILBOX_MENU;
    143:          phone.speak(MAILBOX_MENU_TEXT);
    144:       }
    145:    }
    146:
    147:    /**
    148:       Respond to the user's selection from mailbox menu.
    149:       @param key the phone key pressed by the user
    150:    */
    151:    private void mailboxMenu(String key)
    152:    {
    153:       if (key.equals("1"))
    154:       {
    155:          state = MESSAGE_MENU;
    156:          phone.speak(MESSAGE_MENU_TEXT);
    157:       }
    158:       else if (key.equals("2"))
    159:       {
    160:          state = CHANGE_PASSCODE;
    161:          phone.speak("Enter new passcode followed by the # key");
    162:       }
    163:       else if (key.equals("3"))
    164:       {
    165:          state = CHANGE_GREETING;
    166:          phone.speak("Record your greeting, then press the # key");
    167:       }
    168:    }
    169:
    170:    /**
    171:       Respond to the user's selection from message menu.
    172:       @param key the phone key pressed by the user
    173:    */
    174:    private void messageMenu(String key)
    175:    {
    176:       if (key.equals("1"))
    177:       {
    178:          String output = "";
    179:          Message m = currentMailbox.getCurrentMessage();
    180:          if (m == null) output += "No messages." + "\n";
    181:          else output += m.getText() + "\n";
    182:          output += MESSAGE_MENU_TEXT;
    183:          phone.speak(output);
    184:       }
    185:       else if (key.equals("2"))
    186:       {
    187:          currentMailbox.saveCurrentMessage();
    188:          phone.speak(MESSAGE_MENU_TEXT);
    189:       }
    190:       else if (key.equals("3"))
    191:       {
    192:          currentMailbox.removeCurrentMessage();
    193:          phone.speak(MESSAGE_MENU_TEXT);
    194:       }
    195:       else if (key.equals("4"))
    196:       {
    197:          state = MAILBOX_MENU;
    198:          phone.speak(MAILBOX_MENU_TEXT);
    199:       }
    200:    }
    201:
    202:    private MailSystem system;
    203:    private Mailbox currentMailbox;
    204:    private String currentRecording;
    205:    private String accumulatedKeys;
    206:    private Telephone phone;
    207:    private int state;
    208:
    209:    private static final int DISCONNECTED = 0;
    210:    private static final int CONNECTED = 1;
    211:    private static final int RECORDING = 2;
    212:    private static final int MAILBOX_MENU = 3;
    213:    private static final int MESSAGE_MENU = 4;
    214:    private static final int CHANGE_PASSCODE = 5;
    215:    private static final int CHANGE_GREETING = 6;
    216:
    217:    private static final String INITIAL_PROMPT =
    218:       "Enter mailbox number followed by #";
    219:    private static final String MAILBOX_MENU_TEXT =
    220:       "Enter 1 to listen to your messages\n"
    221:       + "Enter 2 to change your passcode\n"
    222:       + "Enter 3 to change your greeting";
    223:    private static final String MESSAGE_MENU_TEXT =
    224:       "Enter 1 to listen to the current message\n"
    225:       + "Enter 2 to save the current message\n"
    226:       + "Enter 3 to delete the current message\n"
    227:       + "Enter 4 to return to the main menu";
    228: }
    229:
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    239: