Class DFA

java.lang.Object
jflex.dfa.DFA
Direct Known Subclasses:
DeprecatedDfa
public class DFA extends Object
Deterministic finite automata representation in JFlex. Contains minimization algorithm.
Version:
JFlex 1.9.1
Author:
Gerwin Klein

  • Field Details

    • NO_TARGET

      public static final int NO_TARGET
      The code for "no target state" in the transition table.
      See Also:

  • Constructor Details

    • DFA

      public DFA(int numEntryStates, int numInputs, int numLexStates)
      Constructor for a deterministic finite automata.

  • Method Details

    • setEntryState

      public void setEntryState(int eState, int trueState)
      Sets the state of the entry.
      Parameters:
      eState - entry state.
      trueState - whether it is the current state.

    • setAction

      public void setAction(int state, Action stateAction)
      Sets the action.
      Parameters:
      state - a int.
      stateAction - a Action object.

    • setFinal

      public void setFinal(int state, boolean isFinalState)
      setFinal.
      Parameters:
      state - a int.
      isFinalState - a boolean.

    • addTransition

      public void addTransition(int start, int input, int dest)
      addTransition.
      Parameters:
      start - a int.
      input - a int.
      dest - a int.

    • lookaheadUsed

      public boolean lookaheadUsed()

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object

    • equals

      public boolean equals(@Nullable Object obj)
      Overrides:
      equals in class Object

    • writeDot

      public void writeDot(File file)
      Writes a dot-file representing this DFA.
      Parameters:
      file - output file.

    • checkActions

      public void checkActions(LexScan scanner, LexParse parser)
      Checks 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

    • isMinimized

      public boolean isMinimized()

    • toString

      public String toString(int[] a)
      Returns a representation of this DFA.

    • numInput

      public int numInput()

    • numStates

      public int numStates()

    • numLexStates

      public int numLexStates()

    • entryState

      public int entryState(int i)

    • isFinal

      public boolean isFinal(int i)

    • table

      public int table(int i, int j)

    • action

      public Action action(int i)