Class CommandProcessor

java.lang.Object

CommandProcessor

public class CommandProcessor
extends java.lang.Object

The most important class. This processes all the commands issued by the users

Constructor Summary

Constructors

Constructor and Description
CommandProcessor()

Method Summary

Modifier and Type	Method and Description
static void	addFriend(java.lang.String nickname) Adds a new friend.
static void	addFriendToBcast(java.lang.String friendNickname, java.lang.String bcastNickname) adds a friend to a broadcast list.
static void	doLogin() A method to do login.
static void	doLogout() A method to logout the user.
static void	processCommand(java.lang.String command) Processes commands issued by the logged in user.
static void	readMessage(java.lang.String nickname, boolean enforceUnread) Displays messages from the message list of the user logged in.
static void	removeBroadcastcast(java.lang.String nickname) A method to remove a broadcast list.
static void	removeFriend(java.lang.String nickname) removes an existing friend.
static void	removeFriendFromBcast(java.lang.String friendNickname, java.lang.String bcastNickname) removes a friend from a broadcast list.
static void	search(java.lang.String word, boolean searchByFirstName) Method to do a user search.
static void	sendMessage(java.lang.String nickname, java.lang.String message) A method to send a message.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CommandProcessor

public CommandProcessor()

Method Detail

doLogin

public static void doLogin()
                    throws WhatsAppException

A method to do login. Should show LOGIN_PROMPT for the nickname, PASSWORD_PROMPT for the password. Says SUCCESSFULLY_LOGGED_IN is successfully logs in someone. Must set the logged in user in the Config instance here

Throws:

WhatsAppException - if the credentials supplied by the user are invalid, throw this exception with INVALID_CREDENTIALS as the message

doLogout

public static void doLogout()

A method to logout the user. Should print SUCCESSFULLY_LOGGED_OUT when done.

sendMessage

public static void sendMessage(java.lang.String nickname,
                               java.lang.String message)
                        throws WhatsAppRuntimeException,
                               WhatsAppException

A method to send a message. Handles both one to one and broadcasts MESSAGE_SENT_SUCCESSFULLY if sent successfully.

Parameters:

nickname - - can be a friend or broadcast list nickname

message - - message to send

Throws:

WhatsAppRuntimeException - simply pass this untouched from the constructor of the Message class

WhatsAppException - throw this with one of CANT_SEND_YOURSELF, NICKNAME_DOES_NOT_EXIST messages

readMessage

public static void readMessage(java.lang.String nickname,
                               boolean enforceUnread)

Displays messages from the message list of the user logged in. Prints the messages in the format specified by MESSAGE_FORMAT. Says NO_MESSAGES if no messages can be displayed at the present time

Parameters:

nickname - - send a null in this if you want to display messages related to everyone. This can be a broadcast nickname also.

enforceUnread - - send true if you want to display only unread messages.

search

public static void search(java.lang.String word,
                          boolean searchByFirstName)

Method to do a user search. Does a case insensitive "contains" search on either first name or last name. Displays user information as specified by the USER_DISPLAY_FOR_SEARCH format. Says NO_RESULTS_FOUND is nothing found.

Parameters:

word - - word to search for

searchByFirstName - - true if searching for first name. false for last name

addFriend

public static void addFriend(java.lang.String nickname)
                      throws WhatsAppException

Adds a new friend. Says SUCCESSFULLY_ADDED if added. Hint: use the addFriend method of the User class.

Parameters:

nickname - - nickname of the user to add as a friend

Throws:

WhatsAppException - simply pass the exception thrown from the addFriend method of the User class

removeFriend

public static void removeFriend(java.lang.String nickname)
                         throws WhatsAppException

removes an existing friend. Says NOT_A_FRIEND if not a friend to start with, SUCCESSFULLY_REMOVED if removed. Additionally removes the friend from any broadcast list she is a part of

Parameters:

nickname - nickname of the user to remove from the friend list

Throws:

WhatsAppException - simply pass the exception from the removeFriend method of the User class

addFriendToBcast

public static void addFriendToBcast(java.lang.String friendNickname,
                                    java.lang.String bcastNickname)
                             throws WhatsAppException

adds a friend to a broadcast list. Says SUCCESSFULLY_ADDED if added

Parameters:

friendNickname - the nickname of the friend to add to the list

bcastNickname - the nickname of the list to add the friend to

Throws:

WhatsAppException - throws a new instance of this exception with one of NOT_A_FRIEND (if friendNickname is not a friend), BCAST_LIST_DOES_NOT_EXIST (if the broadcast list does not exist), ALREADY_PRESENT (if the friend is already a member of the list), CANT_ADD_YOURSELF_TO_BCAST (if attempting to add the user to one of his own lists

removeFriendFromBcast

public static void removeFriendFromBcast(java.lang.String friendNickname,
                                         java.lang.String bcastNickname)
                                  throws WhatsAppException

removes a friend from a broadcast list. Says SUCCESSFULLY_REMOVED if removed

Parameters:

friendNickname - the friend nickname to remove from the list

bcastNickname - the nickname of the list from which to remove the friend

Throws:

WhatsAppException - throw a new instance of this with one of these messages: NOT_A_FRIEND (if friendNickname is not a friend), BCAST_LIST_DOES_NOT_EXIST (if the broadcast list does not exist), NOT_PART_OF_BCAST_LIST (if the friend is not a part of the list)

removeBroadcastcast

public static void removeBroadcastcast(java.lang.String nickname)
                                throws WhatsAppException

A method to remove a broadcast list. Says BCAST_LIST_DOES_NOT_EXIST if there is no such list to begin with and SUCCESSFULLY_REMOVED if removed. Hint: use the removeBroadcastList method of the User class

Parameters:

nickname - the nickname of the broadcast list which is to be removed from the currently logged in user

Throws:

WhatsAppException - Simply pass the exception returned from the removeBroadcastList method of the User class

processCommand

public static void processCommand(java.lang.String command)

Processes commands issued by the logged in user. Says INVALID_COMMAND for anything not conforming to the syntax. This basically uses the rest of the methods in this class. These methods throw either or both an instance of WhatsAppException/WhatsAppRuntimeException. You ought to catch such exceptions here and print the messages in them. Note that this method does not throw any exceptions. Handle all exceptions by catch them here!

Parameters:

command - the command string issued by the user