SAutomaton (jrexx Developer Documentation)

This class represents a (non-)deterministic final automaton (NFA/DFA). Use this class to create an automaton manually by adding states to the automaton and transitions to other states or to browse through the automaton's states and implement your own matching strategies.
to create an automaton manually try


 
import com.karneim.util.collection.set.*;
 
public class Test {
 
  public static void main(String[] args) {
 
    SAutomaton automaton = new SAutomaton();
 
    IStatePro s1 = automaton.addState(false);
 
    IStatePro s2 = automaton.addState(true);
 
    s1.addTransition(new CharSet("0123456789"),s2);
 
    s2.addTransition(new CharSet("0123456789"),s2);
 
    automaton.setStartState(s1);
 
  }
 
}

to browse through the automaton's states try


 
  final IStatePro startState = automaton.getStartState();
 
  final StateProSet states = new StateProSet(startState);
 
  final Iterator it = states.iterator();
 
  for (IStatePro state=it.next(); state!=null; state=it.next()) {
 
    IStatePro.ITransition[] transitions = state.getTransitions();
 
    for (int i=0; i transitions.length; ++i) {
 
      states.add(transitions[i].getToState());
 
      System.out.println(
 
        "from "    + transitions[i].getFromState()
 
      + " through " + transitions[i].getCharSet()
 
      + " to "      + transitions[i].getToState()
 
      );
 
    }
 
  }

to implement own matching strategies try


 
  /**
 
   * returns true if input is an existing path through automaton's states
 
   * otherwise false.
 
   *
 
  public static boolean incompleteMatch(SAutomaton automaton,String input) {
 
    IState current = automaton.getStartState().visit();
 
    for (int i=0; i input.length(); ++i) {
 
      current = current.next(input.charAt(i));
 
      if (current == null) return false;
 
    }
 
    return true;
 
  }

Version: 1.0

Author: Ralf Meyer

Nested Class Summary
interface	SAutomaton.IChangeListener The listener interface for receiving change events of a SAutomaton.
protected class	SAutomaton.State
protected class	SAutomaton.StatePro
protected class	SAutomaton.Transition

Field Summary
protected AutomatonSet_String	automaton
protected Automaton.IChangedListener	automatonChangedListener
protected LinkedList	listeners
protected HashMap	state2wrapper
protected HashMap	transition2wrapper

Constructor Summary
	SAutomaton() Creates a new empty automaton
	SAutomaton(FSAData data)
	SAutomaton(InputStream automatonDataStream)
protected	SAutomaton(AutomatonSet_String automaton)

Method Summary
void	addAll(SAutomaton automaton)
void	addChangeListener(SAutomaton.IChangeListener listener) Adds the specified listener to receive change events from this automaton.
IStatePro	addState() Adds a new non final state to this automaton.
IStatePro	addState(boolean isFinal) Adds a new final or non final state to this automaton.
void	clear() Removes all states of this automaton.
void	complement()
protected Automaton.IChangedListener	getAutomatonChangedListener()
IStatePro	getStartState() Returns the current start state of the automaton. important: The result is null, if and only if the current start state is null
StateProSet	getStates() Returns all states of this automaton whatever they are reachable through the current start state or not.
protected void	init(FSAData a)
boolean	isDeterministic()
void	minimize() Minimizes this automaton as much as possible.
void	removeAll(SAutomaton automaton)
boolean	removeChangeListener(SAutomaton.IChangeListener listener) Removes the specified listener so that it no longer receives change events from this automaton.
boolean	removeState(IStatePro state) Removes the specified state from this automaton.
void	retainAll(SAutomaton automaton)
void	setStartState(IStatePro state) Sets the automaton's start state to the specified state.
FSAData	toData()
void	toData(OutputStream automatonDataStream)
protected static FSAData	toFSAData(Object obj)
String	toString()

Field Detail

automaton

automatonChangedListener

Adds the specified listener to receive change events from this automaton. The listener will be registered as listener in any case, even if it has been registered yet. If a listener instance is added two times, it will receive events twice. important: don't forget to remove the listener, if you don't need it any longer but still have the automaton in use. Otherwise your listener won't be carbage collected (because it is registered with this automaton) and still will receive events.

addState

clear

complement

getAutomatonChangedListener

Removes the specified listener so that it no longer receives change events from this automaton. If the listener instance is registered more than ones, only one instance will be removed.

Parameters: listener

Returns: true if the listener was registered else false

UNKNOWN: IllegalArgumentException - if null is passed as listener

removeState

Removes the specified state from this automaton.
First all transitions pointing to state are removed and then the state itself.
If state is this automaton's start state then first of all this automaton's start state is set to null.
important: the specified state must have been created via the addState method of this automaton otherwise an IllegalArgumentException is thrown.

Parameters: state

Returns: true if this automaton owns the specified state else false

retainAll

setStartState

Sets the automaton's start state to the specified state. If the automaton should have no start state pass null.
important: the specified state must be a state of this automaton which means
a) the state must have been created via the addState() method of this automaton
b) the state must not have been removed from this automaton via the removeState method

Parameters: state

Class SAutomaton