org.opentripplanner.routing.automata

Class DFA

java.lang.Object

org.opentripplanner.routing.automata.NFA

org.opentripplanner.routing.automata.DFA

public class DFA
extends NFA

A deterministic finite automaton, with a transition table for fast incremental parsing.

Author:

abyrd

Field Summary

Fields inherited from class org.opentripplanner.routing.automata.NFA

acceptStates, nt, startStates

Constructor Summary

Constructors

Constructor and Description
DFA(NFA nfa) Build a deterministic finite automaton from an existing, potentially nondeterministic one.
DFA(Nonterminal nonterminal) Build a deterministic finite automaton that accepts the given nonterminal from a grammar

Method Summary

Modifier and Type	Method and Description
boolean	accepts(int state)
String	dumpTable() Dump the transition table to a string.
boolean	parse(int... terminals) Return true if this DFA (and the nonterminal it is built from) match the given sequence of terminal symbols.
int	transition(int initState, int terminal) this method will not catch reject states; the caller must do so.

Methods inherited from class org.opentripplanner.routing.automata.NFA

minimize, relabelNodes, reverse, toDFA, toGraphViz

Methods inherited from class java.lang.Object

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

Constructor Detail

DFA

public DFA(NFA nfa)

Build a deterministic finite automaton from an existing, potentially nondeterministic one.

DFA

public DFA(Nonterminal nonterminal)

Build a deterministic finite automaton that accepts the given nonterminal from a grammar

Method Detail

dumpTable

public String dumpTable()

Dump the transition table to a string. Rows are states, columns are terminal symbols.

parse

public boolean parse(int... terminals)

Return true if this DFA (and the nonterminal it is built from) match the given sequence of terminal symbols.

transition

public int transition(int initState,
                      int terminal)

this method will not catch reject states; the caller must do so.

accepts

public boolean accepts(int state)