nl.inl.blacklab.search.fimatch

Class NfaStateOrAcyclic

java.lang.Object

nl.inl.blacklab.search.fimatch.NfaState

nl.inl.blacklab.search.fimatch.NfaStateOrAcyclic

public class NfaStateOrAcyclic
extends NfaState

An OR-node where none of the clauses cycle back to an earlier node. This can be evaluated more efficiently, by finding matches for each of the clauses, and then continuing at nextState from each of the matches found.

Constructor Summary

Constructors

Constructor and Description
NfaStateOrAcyclic()
NfaStateOrAcyclic(List<NfaState> clauses, boolean clausesAllSameLength)

Method Summary

Modifier and Type	Method and Description
protected String	dumpInternal(Map<NfaState,Integer> stateNrs)
boolean	findMatchesInternal(ForwardIndexDocument fiDoc, int pos, int direction, Set<Integer> matchEnds) Find all matches for this NFA in the token source.
protected void	finishInternal(Set<NfaState> visited) Visit each node and replace dangling arrows (nulls) with the match state.
boolean	hitsAllSameLength(Set<NfaState> statesVisited) Are all hits from this NFA the same length?
int	hitsLengthMax(Set<NfaState> statesVisited) What's the maximum hit length?
int	hitsLengthMin(Set<NfaState> statesVisited) What's the minimum hit length?
boolean	matchesEmptySequence(Set<NfaState> statesVisited) Does this NFA match the empty sequence?
void	setNextState(int input, NfaState state) Set the next state for a given input.

Methods inherited from class nl.inl.blacklab.search.fimatch.NfaState

and, anyToken, dump, dump, emptySet, findMatches, finish, lookupPropertyNumbers, match, matches, or, regex, token, token, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

NfaStateOrAcyclic

public NfaStateOrAcyclic(List<NfaState> clauses,
                         boolean clausesAllSameLength)

NfaStateOrAcyclic

public NfaStateOrAcyclic()

Method Detail

findMatchesInternal

public boolean findMatchesInternal(ForwardIndexDocument fiDoc,
                                   int pos,
                                   int direction,
                                   Set<Integer> matchEnds)

Description copied from class: NfaState

Find all matches for this NFA in the token source.

Parameters:

fiDoc - where to read tokens from

pos - current matching position

direction - matching direction

matchEnds - where to collect the matches found, or null if we don't want to collect them

Returns:

true if any (new) matches were found, false if not

setNextState

public void setNextState(int input,
                         NfaState state)

Description copied from class: NfaState

Set the next state for a given input.

Specified by:

setNextState in class NfaState

Parameters:

input - input

state - next state

matchesEmptySequence

public boolean matchesEmptySequence(Set<NfaState> statesVisited)

Description copied from class: NfaState

Does this NFA match the empty sequence?

Specified by:

matchesEmptySequence in class NfaState

Parameters:

statesVisited - states we've already visited, so we can deal with cycles

Returns:

true if it matches the empty sequence, false if not

hitsAllSameLength

public boolean hitsAllSameLength(Set<NfaState> statesVisited)

Description copied from class: NfaState

Are all hits from this NFA the same length?

Specified by:

hitsAllSameLength in class NfaState

Parameters:

statesVisited - states we've already visited, so we can deal with cycles

Returns:

true if all hits are the same length, false if not

hitsLengthMin

public int hitsLengthMin(Set<NfaState> statesVisited)

Description copied from class: NfaState

What's the minimum hit length?

Specified by:

hitsLengthMin in class NfaState

Parameters:

statesVisited - states we've already visited, so we can deal with cycles

Returns:

minimum hit length

hitsLengthMax

public int hitsLengthMax(Set<NfaState> statesVisited)

Description copied from class: NfaState

What's the maximum hit length?

Specified by:

hitsLengthMax in class NfaState

Parameters:

statesVisited - states we've already visited, so we can deal with cycles

Returns:

maximum hit length

dumpInternal

protected String dumpInternal(Map<NfaState,Integer> stateNrs)

Specified by:

dumpInternal in class NfaState

finishInternal

protected void finishInternal(Set<NfaState> visited)

Description copied from class: NfaState

Visit each node and replace dangling arrows (nulls) with the match state.

Specified by:

finishInternal in class NfaState

Parameters:

visited - nodes visited so far, this one included. finish() uses this to make sure we don't visit the same node twice, so always call finish() in your implementations, not finishInternal().