Package org.apache.lucene.search
Class TermAutomatonQuery
- java.lang.Object
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- org.apache.lucene.search.Query
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- org.apache.lucene.search.TermAutomatonQuery
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- All Implemented Interfaces:
Accountable
public class TermAutomatonQuery extends Query implements Accountable
A proximity query that lets you express an automaton, whose transitions are terms, to match documents. This is a generalization of other proximity queries likePhraseQuery
,MultiPhraseQuery
andSpanNearQuery
. It is likely slow, since it visits any document having any of the terms (i.e. it acts like a disjunction, not a conjunction likePhraseQuery
), and then it must merge-sort all positions within each document to test whether/how many times the automaton matches.After creating the query, use
createState()
,setAccept(int, boolean)
,addTransition(int, int, java.lang.String)
andaddAnyTransition(int, int)
to build up the automaton. Once you are done, callfinish()
and then execute the query.This code is very new and likely has exciting bugs!
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Nested Class Summary
Nested Classes Modifier and Type Class Description (package private) static class
TermAutomatonQuery.EnumAndScorer
(package private) class
TermAutomatonQuery.TermAutomatonWeight
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Field Summary
Fields Modifier and Type Field Description private int
anyTermID
private static long
BASE_RAM_BYTES
private Automaton.Builder
builder
(package private) Automaton
det
private java.lang.String
field
private java.util.Map<java.lang.Integer,BytesRef>
idToTerm
private java.util.Map<BytesRef,java.lang.Integer>
termToID
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Constructor Summary
Constructors Constructor Description TermAutomatonQuery(java.lang.String field)
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Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description void
addAnyTransition(int source, int dest)
Adds a transition matching any term.void
addTransition(int source, int dest, java.lang.String term)
Adds a transition to the automaton.void
addTransition(int source, int dest, BytesRef term)
Adds a transition to the automaton.private static boolean
checkFinished(TermAutomatonQuery q)
int
createState()
Returns a new state; state 0 is always the initial state.Weight
createWeight(IndexSearcher searcher, ScoreMode scoreMode, float boost)
Expert: Constructs an appropriate Weight implementation for this query.boolean
equals(java.lang.Object other)
Returns true iffo
is equal to this.private boolean
equalsTo(TermAutomatonQuery other)
void
finish()
Call this once you are done adding states/transitions.void
finish(int maxDeterminizedStates)
Call this once you are done adding states/transitions.private int
getTermID(BytesRef term)
int
hashCode()
Override and implement query hash code properly in a subclass.long
ramBytesUsed()
Return the memory usage of this object in bytes.Query
rewrite(IndexReader reader)
Expert: called to re-write queries into primitive queries.void
setAccept(int state, boolean accept)
Marks the specified state as accept or not.java.lang.String
toDot()
Returns the dot (graphviz) representation of this automaton.java.lang.String
toString(java.lang.String field)
Prints a query to a string, withfield
assumed to be the default field and omitted.void
visit(QueryVisitor visitor)
Recurse through the query tree, visiting any child queries-
Methods inherited from class org.apache.lucene.search.Query
classHash, sameClassAs, toString
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Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
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Methods inherited from interface org.apache.lucene.util.Accountable
getChildResources
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Field Detail
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BASE_RAM_BYTES
private static final long BASE_RAM_BYTES
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field
private final java.lang.String field
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builder
private final Automaton.Builder builder
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det
Automaton det
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termToID
private final java.util.Map<BytesRef,java.lang.Integer> termToID
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idToTerm
private final java.util.Map<java.lang.Integer,BytesRef> idToTerm
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anyTermID
private int anyTermID
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Method Detail
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createState
public int createState()
Returns a new state; state 0 is always the initial state.
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setAccept
public void setAccept(int state, boolean accept)
Marks the specified state as accept or not.
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addTransition
public void addTransition(int source, int dest, java.lang.String term)
Adds a transition to the automaton.
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addTransition
public void addTransition(int source, int dest, BytesRef term)
Adds a transition to the automaton.
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addAnyTransition
public void addAnyTransition(int source, int dest)
Adds a transition matching any term.
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finish
public void finish()
Call this once you are done adding states/transitions.
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finish
public void finish(int maxDeterminizedStates)
Call this once you are done adding states/transitions.- Parameters:
maxDeterminizedStates
- Maximum number of states created when determinizing the automaton. Higher numbers allow this operation to consume more memory but allow more complex automatons.
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createWeight
public Weight createWeight(IndexSearcher searcher, ScoreMode scoreMode, float boost) throws java.io.IOException
Description copied from class:Query
Expert: Constructs an appropriate Weight implementation for this query.Only implemented by primitive queries, which re-write to themselves.
- Overrides:
createWeight
in classQuery
scoreMode
- How the produced scorers will be consumed.boost
- The boost that is propagated by the parent queries.- Throws:
java.io.IOException
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toString
public java.lang.String toString(java.lang.String field)
Description copied from class:Query
Prints a query to a string, withfield
assumed to be the default field and omitted.
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getTermID
private int getTermID(BytesRef term)
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equals
public boolean equals(java.lang.Object other)
Returns true iffo
is equal to this.- Specified by:
equals
in classQuery
- See Also:
Query.sameClassAs(Object)
,Query.classHash()
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checkFinished
private static boolean checkFinished(TermAutomatonQuery q)
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equalsTo
private boolean equalsTo(TermAutomatonQuery other)
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hashCode
public int hashCode()
Description copied from class:Query
Override and implement query hash code properly in a subclass. This is required so thatQueryCache
works properly.- Specified by:
hashCode
in classQuery
- See Also:
Query.equals(Object)
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ramBytesUsed
public long ramBytesUsed()
Description copied from interface:Accountable
Return the memory usage of this object in bytes. Negative values are illegal.- Specified by:
ramBytesUsed
in interfaceAccountable
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toDot
public java.lang.String toDot()
Returns the dot (graphviz) representation of this automaton. This is extremely useful for visualizing the automaton.
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rewrite
public Query rewrite(IndexReader reader) throws java.io.IOException
Description copied from class:Query
Expert: called to re-write queries into primitive queries. For example, a PrefixQuery will be rewritten into a BooleanQuery that consists of TermQuerys.
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visit
public void visit(QueryVisitor visitor)
Description copied from class:Query
Recurse through the query tree, visiting any child queries
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