jflex

Class DFA

java.lang.Object

jflex.DFA

public final class DFA
extends Object

DFA representation in JFlex. Contains minimization algorithm.

Version:

JFlex 1.7.0-SNAPSHOT

Author:

Gerwin Klein

Field Summary

Fields

Modifier and Type	Field and Description
static int	NO_TARGET The code for "no target state" in the transition table.

Constructor Summary

Constructors

Constructor and Description
DFA(int numEntryStates, int numInp, int numLexStates)

Method Summary

Methods

Modifier and Type	Method and Description
void	addTransition(int start, int input, int dest)
void	checkActions(LexScan scanner, LexParse parser) Check that all actions can actually be matched in this DFA.
String	dotFormat()
void	minimize() Implementation of Hopcroft's O(n log n) minimization algorithm, follows description by D.
boolean[][]	old_minimize() Much simpler, but slower and less memory efficient minimization algorithm.
void	printBlocks(int[] b, int[] b_f, int[] b_b, int last)
void	printInvDelta(int[][] inv_delta, int[] inv_delta_set)
void	printL(int[] l_f, int[] l_b, int anchor)
void	printTable(boolean[][] equiv)
void	setAction(int state, Action stateAction)
void	setEntryState(int eState, int trueState)
void	setFinal(int state, boolean isFinalState)
String	toString()
String	toString(int[] a)
void	writeDot(File file)

Methods inherited from class java.lang.Object

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

Field Detail

NO_TARGET

public static final int NO_TARGET

The code for "no target state" in the transition table.

See Also:

Constant Field Values

Constructor Detail

DFA

public DFA(int numEntryStates,
   int numInp,
   int numLexStates)

Method Detail

setEntryState

public void setEntryState(int eState,
                 int trueState)

setAction

public void setAction(int state,
             Action stateAction)

setFinal

public void setFinal(int state,
            boolean isFinalState)

addTransition

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

toString

public String toString()

Overrides:

toString in class Object

writeDot

public void writeDot(File file)

dotFormat

public String dotFormat()

checkActions

public void checkActions(LexScan scanner,
                LexParse parser)

Check that all actions can actually be matched in this DFA.

minimize

public void minimize()

Implementation of Hopcroft's O(n log n) minimization algorithm, follows description by D. Gries. Time: O(n log n) Space: O(c n), size < 4*(5*c*n + 13*n + 3*c) byte

toString

public String toString(int[] a)

printBlocks

public void printBlocks(int[] b,
               int[] b_f,
               int[] b_b,
               int last)

printL

public void printL(int[] l_f,
          int[] l_b,
          int anchor)

old_minimize

public boolean[][] old_minimize()

Much simpler, but slower and less memory efficient minimization algorithm.

Returns:

the equivalence relation on states.

printInvDelta

public void printInvDelta(int[][] inv_delta,
                 int[] inv_delta_set)

printTable

public void printTable(boolean[][] equiv)