finiteAutomata
Class NFAMenu

java.lang.Object
  finiteAutomata.NFAMenu

public class NFAMenu
extends java.lang.Object

Menu and query methods for the NFA class.

Version:

Fall 2007

Author:

Barbara Wahl

Constructor Summary

NFAMenu()

Method Summary

protected static void	addEpsilonDialog(NFA nfa) Queries user regarding which epsilon transition to add.
protected static void	addTransitionDialog(NFA nfa) Queries user regarding which symbol-consuming transition to add.
protected static void	changeTransition(NFA nfa, int n) Takes action based on provided transition change choice code.
protected static int	changeTransitionDialog() Queries user regarding desired transition change.
protected static int	constructorMenu() Displays constructor menu options and prompts user to choose an action.
protected static boolean	constructorMenuHandler(NFA nfa, int choice) Takes action based on the provided constructor menu choice code.
static void	main(java.lang.String[] args)
protected static void	queryAlphabet(NFA nfa) Queries user to obtain alphabet of input symbols.
protected static void	queryFinal(NFA nfa) Queries user to determine which states are final.
protected static void	queryNumStates(NFA nfa) Prints constructor menu heading, and queries user until valid (positive) number of states is obtained.
protected static boolean	queryPredefined() Asks user if they want to use a pre-defined NFA.
protected static void	removeEpsilonDialog(NFA nfa) Queries user regarding which epsilon transition to remove.
protected static void	removeTransitionDialog(NFA nfa) Queries user regarding which symbol-consuming transition to remove.
protected static int	runMenu() Displays run menu options and prompts user to make a choice of action.
protected static boolean	runMenuHandler(NFA nfa, int choice) Takes action based on the provided run menu choice code.
protected static void	testingDialog(NFA nfa) Allows the user to repeatedly test strings on an NFA.

Methods inherited from class java.lang.Object

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

Constructor Detail

NFAMenu

public NFAMenu()

Method Detail

queryPredefined

protected static boolean queryPredefined()

Asks user if they want to use a pre-defined NFA.

Returns:

true iff user response begins with 'Y' or 'y'

queryNumStates

protected static void queryNumStates(NFA nfa)

Prints constructor menu heading, and queries user until valid (positive) number of states is obtained.

Parameters:

nfa - the NFA being operated on

Postcondition:

nfa.numStates is initialized to a positive integer value

queryAlphabet

protected static void queryAlphabet(NFA nfa)

Queries user to obtain alphabet of input symbols.

Parameters:

nfa - the NFA being operated on

Postcondition:

Alphabet of the specified NFA is initialized according to user response

queryFinal

protected static void queryFinal(NFA nfa)

Queries user to determine which states are final.

Parameters:

nfa - the NFA being operated on

Postcondition:

isFinal array is initialized according to user responses

constructorMenu

protected static int constructorMenu()

Displays constructor menu options and prompts user to choose an action.

Returns:

valid choice number (1 thru 6)

constructorMenuHandler

protected static boolean constructorMenuHandler(NFA nfa,
                                                int choice)

Takes action based on the provided constructor menu choice code.

Parameters:

nfa - the NFA being operated on

choice - constructor menu choice code

Returns:

true iff user is done with menu options

Precondition:

1 <= choice <= 6

runMenu

protected static int runMenu()

Displays run menu options and prompts user to make a choice of action.

Returns:

integer choice code (1 through 9)

runMenuHandler

protected static boolean runMenuHandler(NFA nfa,
                                        int choice)

Takes action based on the provided run menu choice code.

Parameters:

nfa - the NFA being operated on

choice - run menu choice code

Returns:

true iff user is done with menu options

Precondition:

1 <= choice <= 9

changeTransitionDialog

protected static int changeTransitionDialog()

Queries user regarding desired transition change.

Returns:

transition change choice code (1 through 4)

changeTransition

protected static void changeTransition(NFA nfa,
                                       int n)

Takes action based on provided transition change choice code.

Parameters:

nfa - the NFA being operated on

n - transition change choice code

Postcondition:

makes changes to transition array and re-calculates the equivalent DFA

removeEpsilonDialog

protected static void removeEpsilonDialog(NFA nfa)

Queries user regarding which epsilon transition to remove.

Parameters:

nfa - the NFA being operated on

Postcondition:

if user provides valid state numbers i and j, epsilon[i][j] is set to false and the equivalent DFA is re-calculated

removeTransitionDialog

protected static void removeTransitionDialog(NFA nfa)

Queries user regarding which symbol-consuming transition to remove.

Parameters:

nfa - the NFA being operated on

Postcondition:

if user provides valid state numbers i and j, and valid symbol s, the transition array is changed accordingly and the equivalent DFA is re-calculated

addEpsilonDialog

protected static void addEpsilonDialog(NFA nfa)

Queries user regarding which epsilon transition to add.

Parameters:

nfa - the NFA being operated on

Postcondition:

if user provides valid state numbers i and j, epsilon[i][j] is set to true and the equivalent DFA is re-calculated

addTransitionDialog

protected static void addTransitionDialog(NFA nfa)

Queries user regarding which symbol-consuming transition to add.

Parameters:

nfa - the NFA being operated on

Postcondition:

if user provides valid state numbers i and j, and valid symbol s, the transition array is changed accordingly and the equivalent DFA is re-calculated

testingDialog

protected static void testingDialog(NFA nfa)

Allows the user to repeatedly test strings on an NFA.

Parameters:

nfa - the NFA being operated on

Postcondition:

Each input string is echoed back to the console with a report of the string's length and whether or not it is accepted

main

public static void main(java.lang.String[] args)

Parameters:

args -