org.apache.lucene.util.automaton

Class CompiledAutomaton

java.lang.Object

org.apache.lucene.util.automaton.CompiledAutomaton

public class CompiledAutomaton
extends Object

Immutable class holding compiled details for a given Automaton. The Automaton is deterministic, must not have dead states but is not necessarily minimal.

WARNING: This API is experimental and might change in incompatible ways in the next release.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	CompiledAutomaton.AUTOMATON_TYPE Automata are compiled into different internal forms for the most efficient execution depending upon the language they accept.

Field Summary

Fields

Modifier and Type	Field and Description
BytesRef	commonSuffixRef Shared common suffix accepted by the automaton.
Boolean	finite Indicates if the automaton accepts a finite set of strings.
ByteRunAutomaton	runAutomaton Matcher for quickly determining if a byte[] is accepted.
Transition[][]	sortedTransitions Two dimensional array of transitions, indexed by state number for traversal.
BytesRef	term For CompiledAutomaton.AUTOMATON_TYPE.PREFIX, this is the prefix term; for CompiledAutomaton.AUTOMATON_TYPE.SINGLE this is the singleton term.
CompiledAutomaton.AUTOMATON_TYPE	type

Constructor Summary

Constructors

Constructor and Description
CompiledAutomaton(Automaton automaton)
CompiledAutomaton(Automaton automaton, Boolean finite, boolean simplify)

Method Summary

Methods

Modifier and Type	Method and Description
BytesRef	floor(BytesRef input, BytesRef output) Finds largest term accepted by this Automaton, that's <= the provided input term.
TermsEnum	getTermsEnum(Terms terms)

Methods inherited from class java.lang.Object

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

Field Detail

type

public final CompiledAutomaton.AUTOMATON_TYPE type

term

public final BytesRef term

For CompiledAutomaton.AUTOMATON_TYPE.PREFIX, this is the prefix term; for CompiledAutomaton.AUTOMATON_TYPE.SINGLE this is the singleton term.

runAutomaton

public final ByteRunAutomaton runAutomaton

Matcher for quickly determining if a byte[] is accepted. only valid for CompiledAutomaton.AUTOMATON_TYPE.NORMAL.

sortedTransitions

public final Transition[][] sortedTransitions

Two dimensional array of transitions, indexed by state number for traversal. The state numbering is consistent with runAutomaton. Only valid for CompiledAutomaton.AUTOMATON_TYPE.NORMAL.

commonSuffixRef

public final BytesRef commonSuffixRef

Shared common suffix accepted by the automaton. Only valid for CompiledAutomaton.AUTOMATON_TYPE.NORMAL, and only when the automaton accepts an infinite language.

finite

public final Boolean finite

Indicates if the automaton accepts a finite set of strings. Null if this was not computed. Only valid for CompiledAutomaton.AUTOMATON_TYPE.NORMAL.

Constructor Detail

CompiledAutomaton

public CompiledAutomaton(Automaton automaton)

CompiledAutomaton

public CompiledAutomaton(Automaton automaton,
                 Boolean finite,
                 boolean simplify)

Method Detail

getTermsEnum

public TermsEnum getTermsEnum(Terms terms)
                       throws IOException

Throws:

IOException

floor

public BytesRef floor(BytesRef input,
             BytesRef output)

Finds largest term accepted by this Automaton, that's <= the provided input term. The result is placed in output; it's fine for output and input to point to the same BytesRef. The returned result is either the provided output, or null if there is no floor term (ie, the provided input term is before the first term accepted by this Automaton).