JFlex

Class NFA

public final class NFA extends Object

NFA representation in JFlex. Contains algorithms RegExp -> NFA and NFA -> DFA.
Constructor Summary
NFA(int numInput, int estSize)
NFA(int numInput, LexScan scanner, RegExps regExps, Macros macros, CharClasses classes)
Construct new NFA.
Method Summary
voidaddEpsilonTransition(int start, int dest)
voidaddRegExp(int regExpNum)
Add a regexp to this NFA.
voidaddStandaloneRule()
Add a standalone rule that has minimum priority, fires a transition on all single input characters and has a "print yytext" action.
voidaddTransition(int start, int input, int dest)
StringdotFormat()
voiddumpTable()
DFAgetDFA()
Returns an DFA that accepts the same language as this NFA.
IntPairinsertNFA(RegExp regExp)
Constructs an NFA for regExp such that the NFA has exactly one start state, exactly one end state, no transitions leading out of the end state no transitions leading into the start state
intnumEntryStates()
StringtoString()
voidwriteDot(File file)

Constructor Detail

NFA

public NFA(int numInput, int estSize)

NFA

public NFA(int numInput, LexScan scanner, RegExps regExps, Macros macros, CharClasses classes)
Construct new NFA. Assumes that lookahead cases and numbers are already resolved in RegExps.

See Also: checkLookAheads

Method Detail

addEpsilonTransition

public void addEpsilonTransition(int start, int dest)

addRegExp

public void addRegExp(int regExpNum)
Add a regexp to this NFA.

Parameters: regExpNum the number of the regexp to add.

addStandaloneRule

public void addStandaloneRule()
Add a standalone rule that has minimum priority, fires a transition on all single input characters and has a "print yytext" action.

addTransition

public void addTransition(int start, int input, int dest)

dotFormat

public String dotFormat()

dumpTable

public void dumpTable()

getDFA

public DFA getDFA()
Returns an DFA that accepts the same language as this NFA. This DFA is usually not minimal.

insertNFA

public IntPair insertNFA(RegExp regExp)
Constructs an NFA for regExp such that the NFA has exactly one start state, exactly one end state, no transitions leading out of the end state no transitions leading into the start state

Parameters: regExp the regular expression to construct the NFA for

Returns: a pair of integers denoting the index of start and end state of the NFA.

numEntryStates

public int numEntryStates()

toString

public String toString()

writeDot

public void writeDot(File file)