Config

java.lang.Object
- Config

```
public class Config
extends java.lang.Object
```
A class implementing the singleton pattern (only one instance of this class can every exist) You cannot instantiate this class from outside by using the new operator. The only way to get the only instance is to use Config.getInstance() This class stores session wide information like the list of all users, the currently logged in user and the console I/O objects. This class contains ALL the strings that you may print ever in this project. This is done in an effort to avoid typos that you can make and to ease testing effort. Some of these strings have %s embedded in them. You must use the String.format method to substitute appropriate strings in these parent strings. For being exactly sure of the locations where these constants ought to be used, thoroughly read ALL the javadocs DO NOT CHANGE THIS CLASS IN ANY WAY

Field Summary

Fields
Modifier and Type	Field and Description
`static java.lang.String`	`ALREADY_A_FRIEND` This is shown if the nickname is already a friend
`static java.lang.String`	`ALREADY_PRESENT` This is shown if the supplied nickname is already present in the broadcast list
`static java.lang.String`	`BCAST_LIST_DOES_NOT_EXIST` This is shown if the broadcast list on which some operation is to be performed does not exist
`static java.lang.String`	`CANT_ADD_YOURSELF_TO_BCAST` This is shown if trying to add the user to one of his own broadcast lists
`static java.lang.String`	`CANT_BE_EMPTY_OR_NULL` Encapsulate this string inside most instances of WhatsAppRuntimeException
`static java.lang.String`	`CANT_BE_OWN_FRIEND` This is shown if trying to add the user as his own friend
`static java.lang.String`	`CANT_LOCATE` This is shown if you cannot locate the nickname supplied for various operations.
`static java.lang.String`	`CANT_SEND_YOURSELF` This is shown if trying to send a message to the same user
`static java.lang.String`	`ENTER_COMMAND` This is the prompt for the logged in user to enter a command
`static java.lang.String`	`ERROR_IO` This is shown if some error occurs while reading the input file
`static java.lang.String`	`EXITING` Show this just before exiting the program when the exit: command is issued
`static java.lang.String`	`FILE_DOES_NOT_EXIST` This is shown if the input file does not exist
`static java.lang.String`	`INVALID_COMMAND` This is shown when the entered command is not valid
`static java.lang.String`	`INVALID_CREDENTIALS` This is shown if the nickname/password pair is incorrect
`static java.lang.String`	`LOGIN_PROMPT` This is shown to the logged in user for getting a command
`static java.lang.String`	`MESSAGE_FORMAT` This is the message template to be used in read message commands
`static java.lang.String`	`MESSAGE_SENT_SUCCESSFULLY` This is shown when a message is sent successfully to the intended receiver(s)
`static java.lang.String`	`NICKNAME_DOES_NOT_EXIST` This is shown if the nickname is not an existing global contact
`static java.lang.String`	`NO_MESSAGES` This is shown if there are no messages to be shown as a result of any of the read messages commands
`static java.lang.String`	`NO_RESULTS_FOUND` This is shown for search commands when they show no users that match the search criteria
`static java.lang.String`	`NOT_A_FRIEND` This is shown if the supplied nickname is not a friend
`static java.lang.String`	`NOT_PART_OF_BCAST_LIST` This is shown if the user nickname is not a member of the broadcast list nickname
`static java.lang.String`	`PASSWORD_PROMPT` This is shown to get the password while login
`static java.lang.String`	`SOMETHING_EXISTS` This is shown if another user with the same nickname already exists
`static java.lang.String`	`SUCCESSFULLY_ADDED` This is shown as part of various add operations that may be performed as part of commands
`static java.lang.String`	`SUCCESSFULLY_LOGGED_IN` This is shown if the user provides valid credentials
`static java.lang.String`	`SUCCESSFULLY_LOGGED_OUT` This is shown after a logout: command is issued by a logged in user
`static java.lang.String`	`SUCCESSFULLY_REMOVED` This is shown as part of various removal operations that may be performed as part of commands
`static java.lang.String`	`USAGE` This is the usage string to be shown if the number of command line arguments is not exactly one
`static java.lang.String`	`USER_DISPLAY_FOR_SEARCH` This is used as a template while showing user information for search commands

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`java.util.List<User>`	`getAllUsers()` returns the list of the global contacts
`java.util.Scanner`	`getConsoleInput()` returns the only way you can obtain input from the keyboard (its a Scanner)
`java.io.PrintStream`	`getConsoleOutput()` returns the only way you can write output to screen (its a PrintStream)
`User`	`getCurrentUser()` returns the currently logged in user object
`static Config`	`getInstance()` This static method is used to return the only instance existing for the Config class
`void`	`setAllUsers(java.util.List<User> allUsers)` sets the list of global users
`void`	`setConsoleInput(java.util.Scanner consoleInput)` a setter for the Scanner object that should be used to obtain input from the keyboard
`void`	`setConsoleOutput(java.io.PrintStream consoleOutput)` a setter for the PrintStream object that should be used to write to the screen
`void`	`setCurrentUser(User currentUser)` sets the currently logged in user object.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - ALREADY_A_FRIEND
```
public static final java.lang.String ALREADY_A_FRIEND
```
    This is shown if the nickname is already a friend
    
    See Also:
    
    Constant Field Values
  - ALREADY_PRESENT
```
public static final java.lang.String ALREADY_PRESENT
```
    This is shown if the supplied nickname is already present in the broadcast list
    
    See Also:
    
    Constant Field Values
  - BCAST_LIST_DOES_NOT_EXIST
```
public static final java.lang.String BCAST_LIST_DOES_NOT_EXIST
```
    This is shown if the broadcast list on which some operation is to be performed does not exist
    
    See Also:
    
    Constant Field Values
  - CANT_ADD_YOURSELF_TO_BCAST
```
public static final java.lang.String CANT_ADD_YOURSELF_TO_BCAST
```
    This is shown if trying to add the user to one of his own broadcast lists
    
    See Also:
    
    Constant Field Values
  - CANT_BE_EMPTY_OR_NULL
```
public static final java.lang.String CANT_BE_EMPTY_OR_NULL
```
    Encapsulate this string inside most instances of WhatsAppRuntimeException
    
    See Also:
    
    Constant Field Values
  - CANT_BE_OWN_FRIEND
```
public static final java.lang.String CANT_BE_OWN_FRIEND
```
    This is shown if trying to add the user as his own friend
    
    See Also:
    
    Constant Field Values
  - CANT_LOCATE
```
public static final java.lang.String CANT_LOCATE
```
    This is shown if you cannot locate the nickname supplied for various operations. For places where you must use this string, see the individual javadoc descriptions of methods, specifically of the CommandProcessor class
    
    See Also:
    
    Constant Field Values
  - CANT_SEND_YOURSELF
```
public static final java.lang.String CANT_SEND_YOURSELF
```
    This is shown if trying to send a message to the same user
    
    See Also:
    
    Constant Field Values
  - ENTER_COMMAND
```
public static final java.lang.String ENTER_COMMAND
```
    This is the prompt for the logged in user to enter a command
    
    See Also:
    
    Constant Field Values
  - ERROR_IO
```
public static final java.lang.String ERROR_IO
```
    This is shown if some error occurs while reading the input file
    
    See Also:
    
    Constant Field Values
  - EXITING
```
public static final java.lang.String EXITING
```
    Show this just before exiting the program when the exit: command is issued
    
    See Also:
    
    Constant Field Values
  - FILE_DOES_NOT_EXIST
```
public static final java.lang.String FILE_DOES_NOT_EXIST
```
    This is shown if the input file does not exist
    
    See Also:
    
    Constant Field Values
  - INVALID_COMMAND
```
public static final java.lang.String INVALID_COMMAND
```
    This is shown when the entered command is not valid
    
    See Also:
    
    Constant Field Values
  - INVALID_CREDENTIALS
```
public static final java.lang.String INVALID_CREDENTIALS
```
    This is shown if the nickname/password pair is incorrect
    
    See Also:
    
    Constant Field Values
  - LOGIN_PROMPT
```
public static final java.lang.String LOGIN_PROMPT
```
    This is shown to the logged in user for getting a command
    
    See Also:
    
    Constant Field Values
  - MESSAGE_FORMAT
```
public static final java.lang.String MESSAGE_FORMAT
```
    This is the message template to be used in read message commands
    
    See Also:
    
    Constant Field Values
  - MESSAGE_SENT_SUCCESSFULLY
```
public static final java.lang.String MESSAGE_SENT_SUCCESSFULLY
```
    This is shown when a message is sent successfully to the intended receiver(s)
    
    See Also:
    
    Constant Field Values
  - NICKNAME_DOES_NOT_EXIST
```
public static final java.lang.String NICKNAME_DOES_NOT_EXIST
```
    This is shown if the nickname is not an existing global contact
    
    See Also:
    
    Constant Field Values
  - NOT_A_FRIEND
```
public static final java.lang.String NOT_A_FRIEND
```
    This is shown if the supplied nickname is not a friend
    
    See Also:
    
    Constant Field Values
  - NOT_PART_OF_BCAST_LIST
```
public static final java.lang.String NOT_PART_OF_BCAST_LIST
```
    This is shown if the user nickname is not a member of the broadcast list nickname
    
    See Also:
    
    Constant Field Values
  - NO_MESSAGES
```
public static final java.lang.String NO_MESSAGES
```
    This is shown if there are no messages to be shown as a result of any of the read messages commands
    
    See Also:
    
    Constant Field Values
  - NO_RESULTS_FOUND
```
public static final java.lang.String NO_RESULTS_FOUND
```
    This is shown for search commands when they show no users that match the search criteria
    
    See Also:
    
    Constant Field Values
  - PASSWORD_PROMPT
```
public static final java.lang.String PASSWORD_PROMPT
```
    This is shown to get the password while login
    
    See Also:
    
    Constant Field Values
  - SOMETHING_EXISTS
```
public static final java.lang.String SOMETHING_EXISTS
```
    This is shown if another user with the same nickname already exists
    
    See Also:
    
    Constant Field Values
  - SUCCESSFULLY_ADDED
```
public static final java.lang.String SUCCESSFULLY_ADDED
```
    This is shown as part of various add operations that may be performed as part of commands
    
    See Also:
    
    Constant Field Values
  - SUCCESSFULLY_LOGGED_IN
```
public static final java.lang.String SUCCESSFULLY_LOGGED_IN
```
    This is shown if the user provides valid credentials
    
    See Also:
    
    Constant Field Values
  - SUCCESSFULLY_LOGGED_OUT
```
public static final java.lang.String SUCCESSFULLY_LOGGED_OUT
```
    This is shown after a logout: command is issued by a logged in user
    
    See Also:
    
    Constant Field Values
  - SUCCESSFULLY_REMOVED
```
public static final java.lang.String SUCCESSFULLY_REMOVED
```
    This is shown as part of various removal operations that may be performed as part of commands
    
    See Also:
    
    Constant Field Values
  - USAGE
```
public static final java.lang.String USAGE
```
    This is the usage string to be shown if the number of command line arguments is not exactly one
    
    See Also:
    
    Constant Field Values
  - USER_DISPLAY_FOR_SEARCH
```
public static final java.lang.String USER_DISPLAY_FOR_SEARCH
```
    This is used as a template while showing user information for search commands
    
    See Also:
    
    Constant Field Values
- Method Detail
  - getInstance
```
public static Config getInstance()
```
    This static method is used to return the only instance existing for the Config class
    
    Returns:
    
    the instance of Config
  - getCurrentUser
```
public User getCurrentUser()
```
    returns the currently logged in user object
    
    Returns:
    
    the currently logged in user object
  - setCurrentUser
```
public void setCurrentUser(User currentUser)
```
    sets the currently logged in user object. Use this in the doLogin/doLogout methods of the CommandProcessor class
    
    Parameters:
    
    currentUser - the currently logged in user object. set this to null while logging out
  - getAllUsers
```
public java.util.List<User> getAllUsers()
```
    returns the list of the global contacts
    
    Returns:
    
    the list of all users in WhatsApp
  - setAllUsers
```
public void setAllUsers(java.util.List<User> allUsers)
```
    sets the list of global users
    
    Parameters:
    
    allUsers - the list of all users in WhatsApp
  - getConsoleInput
```
public java.util.Scanner getConsoleInput()
```
    returns the only way you can obtain input from the keyboard (its a Scanner)
    
    Returns:
    
    the Scanner which you should use to get input from the keyboard
  - setConsoleInput
```
public void setConsoleInput(java.util.Scanner consoleInput)
```
    a setter for the Scanner object that should be used to obtain input from the keyboard
    
    Parameters:
    
    consoleInput - the Scanner to be used to obtain input
  - getConsoleOutput
```
public java.io.PrintStream getConsoleOutput()
```
    returns the only way you can write output to screen (its a PrintStream)
    
    Returns:
    
    the PrintStream which you should use to write output to screen
  - setConsoleOutput
```
public void setConsoleOutput(java.io.PrintStream consoleOutput)
```
    a setter for the PrintStream object that should be used to write to the screen
    
    Parameters:
    
    consoleOutput - the PrintStream to be used to write the screen

Class Config

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

ALREADY_A_FRIEND

ALREADY_PRESENT

BCAST_LIST_DOES_NOT_EXIST

CANT_ADD_YOURSELF_TO_BCAST

CANT_BE_EMPTY_OR_NULL

CANT_BE_OWN_FRIEND

CANT_LOCATE

CANT_SEND_YOURSELF

ENTER_COMMAND

ERROR_IO

EXITING

FILE_DOES_NOT_EXIST

INVALID_COMMAND

INVALID_CREDENTIALS

LOGIN_PROMPT

MESSAGE_FORMAT

MESSAGE_SENT_SUCCESSFULLY

NICKNAME_DOES_NOT_EXIST

NOT_A_FRIEND

NOT_PART_OF_BCAST_LIST

NO_MESSAGES

NO_RESULTS_FOUND

PASSWORD_PROMPT

SOMETHING_EXISTS

SUCCESSFULLY_ADDED

SUCCESSFULLY_LOGGED_IN

SUCCESSFULLY_LOGGED_OUT

SUCCESSFULLY_REMOVED

USAGE

USER_DISPLAY_FOR_SEARCH

Method Detail

getInstance

getCurrentUser

setCurrentUser

getAllUsers

setAllUsers

getConsoleInput

setConsoleInput

getConsoleOutput

setConsoleOutput