org.biojava.utils.automata

Class Nfa

java.lang.Object

org.biojava.utils.automata.FiniteAutomaton

org.biojava.utils.automata.Nfa

All Implemented Interfaces:

NfaBuilder

public class Nfa
extends FiniteAutomaton
implements NfaBuilder

Class for modelling non-deterministic finite automata.

This implementation has epsilon and lambda transitions. Both transitions are silent but the former is intended to be optimised away while the latter must be retained during optimisation. This is necessary to implement limited closure for the REs that one may want to build with this NFA.

Since:

1.4

Author:

David Huen

Field Summary

Fields inherited from class org.biojava.utils.automata.FiniteAutomaton

end, nodes, start, transitions

Constructor Summary

Constructors

Constructor and Description
Nfa(String name, FiniteAlphabet alfa)

Method Summary

Modifier and Type	Method and Description
org.biojava.utils.automata.FiniteAutomaton.Transition	addEpsilonTransition(org.biojava.utils.automata.FiniteAutomaton.Node start, org.biojava.utils.automata.FiniteAutomaton.Node end) Add a silent optimisable transition to instance.
org.biojava.utils.automata.FiniteAutomaton.Transition	addLambdaTransition(org.biojava.utils.automata.FiniteAutomaton.Node start, org.biojava.utils.automata.FiniteAutomaton.Node end) Add a silent persistent transition to instance.
protected int	alphaIndex(Symbol sym)
boolean	containsNode(org.biojava.utils.automata.FiniteAutomaton.Node node)

Methods inherited from class org.biojava.utils.automata.FiniteAutomaton

addNode, addTransition, createNodeSet, getAutomaton, getEnd, getNodes, getStart, getTransitions, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.biojava.utils.automata.NfaBuilder

addNode, addTransition, createNodeSet, getAutomaton, getEnd, getNodes, getStart, getTransitions, toString

Constructor Detail

Nfa

public Nfa(String name,
           FiniteAlphabet alfa)

Method Detail

alphaIndex

protected int alphaIndex(Symbol sym)
                  throws IllegalSymbolException

Overrides:

alphaIndex in class FiniteAutomaton

Throws:

IllegalSymbolException

containsNode

public boolean containsNode(org.biojava.utils.automata.FiniteAutomaton.Node node)

addEpsilonTransition

public org.biojava.utils.automata.FiniteAutomaton.Transition addEpsilonTransition(org.biojava.utils.automata.FiniteAutomaton.Node start,
                                                                                  org.biojava.utils.automata.FiniteAutomaton.Node end)

Add a silent optimisable transition to instance.

Specified by:

addEpsilonTransition in interface NfaBuilder

addLambdaTransition

public org.biojava.utils.automata.FiniteAutomaton.Transition addLambdaTransition(org.biojava.utils.automata.FiniteAutomaton.Node start,
                                                                                 org.biojava.utils.automata.FiniteAutomaton.Node end)

Add a silent persistent transition to instance.

Specified by:

addLambdaTransition in interface NfaBuilder