me.jaimegarza.syntax.util

Class NfaUtil

java.lang.Object

me.jaimegarza.syntax.util.NfaUtil

public class NfaUtil
extends Object

Constructor Summary

Constructors

Constructor and Description
NfaUtil()

Method Summary

Modifier and Type	Method and Description
static Construct	alternate(Nfa graph, Construct a, Construct b) constructs a nfa for an alternation (A | B)
static Construct	any(Nfa graph) constructs a nfa for any character
static Construct	character(Nfa graph, char c) constructs a nfa for a character
static Construct	characterClass(Nfa graph, CharacterClass cc) constructs a nfa for a character class
static Construct	concatenate(Nfa graph, Construct from, Construct to) constructs a nfa for a concatenation (A B)
static Dfa	finalize(Nfa graph, String regex, Construct c) Create a new dfa out of a nfa
static Construct	oneOrMany(Nfa graph, Construct a) constructs a nfa for an one to many (A+)
static Construct	optional(Nfa graph, Construct a) constructs a nfa for an option (A?)
static Construct	zeroOrMany(Nfa graph, Construct a) constructs a nfa for a zero to many (A*)

Methods inherited from class java.lang.Object

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

Constructor Detail

NfaUtil

public NfaUtil()

Method Detail

character

public static Construct character(Nfa graph,
                                  char c)

constructs a nfa for a character

      [n] -- c --> [n+1]
 

Parameters:

graph - the graph to which the construct would be added

c - is the character

Returns:

the construct

characterClass

public static Construct characterClass(Nfa graph,
                                       CharacterClass cc)

constructs a nfa for a character class

      [n] -- char-class --> [n+1]
 

Parameters:

graph - the graph to which the construct would be added

cc - is the character class

Returns:

the construct

any

public static Construct any(Nfa graph)

constructs a nfa for any character

      [n] -- <any>--> [n+1]
 

Parameters:

graph - the graph to which the construct would be added

Returns:

the construct

concatenate

public static Construct concatenate(Nfa graph,
                                    Construct from,
                                    Construct to)

constructs a nfa for a concatenation (A B)

      [construct-from] -- ε --> [construct-to]
 

Parameters:

graph - the graph to which the construct would be added

from - is the starting construct

to - is the ending construct

Returns:

the construct

alternate

public static Construct alternate(Nfa graph,
                                  Construct a,
                                  Construct b)

constructs a nfa for an alternation (A | B)

      +--> [construct] --+
      ε                  ε
      |                  |
      |                  V
  -->[n]               [n+1] -->
      |                  ^
      ε                  |
      |                  ε
      +--> [construct] --+
 

Parameters:

graph - the graph to which the construct would be added

a - is the first alternating construct

b - is the second alternating construct

Returns:

the construct

zeroOrMany

public static Construct zeroOrMany(Nfa graph,
                                   Construct a)

constructs a nfa for a zero to many (A*)

      +------------ε------------+
      |                         |
      |                         V
  -->[n]-ε-> [construct] -ε-> [n+1]-->
             ^         |
             |         |         
             +----ε----+
 

Parameters:

graph - the graph to which the construct would be added

a - is the repeating construct

Returns:

the construct

oneOrMany

public static Construct oneOrMany(Nfa graph,
                                  Construct a)

constructs a nfa for an one to many (A+)

  -->[n]-ε-> [construct] -ε-> [n+1]-->
             ^         |
             |         |         
             +----ε----+
 

Parameters:

graph - the graph to which the construct would be added

a - is the repeating construct

Returns:

the construct

optional

public static Construct optional(Nfa graph,
                                 Construct a)

constructs a nfa for an option (A?)

   [construct] 
   |         ^
   |         |         
   +----ε----+
 

Parameters:

graph - the graph to which the construct would be added

a - is the optional construct

Returns:

the construct

finalize

public static Dfa finalize(Nfa graph,
                           String regex,
                           Construct c)

Create a new dfa out of a nfa

Parameters:

graph - is the graph

regex - is the string for the regular expression

c - the starting and ending nodes of the nfa

Returns:

a new DFA