org.apache.lucene.document
Interface Fieldable

All Superinterfaces:

Serializable

All Known Implementing Classes:

AbstractField, Field, NumericField

public interface Fieldable
extends Serializable

Synonymous with Field.

WARNING: This interface may change within minor versions, despite Lucene's backward compatibility requirements. This means new methods may be added from version to version. This change only affects the Fieldable API; other backwards compatibility promises remain intact. For example, Lucene can still read and write indices created within the same major version.

Method Summary

int	getBinaryLength() Returns length of byte[] segment that is used as value, if Field is not binary returned value is undefined
int	getBinaryOffset() Returns offset into byte[] segment that is used as value, if Field is not binary returned value is undefined
byte[]	getBinaryValue() Return the raw byte[] for the binary field.
byte[]	getBinaryValue(byte[] result) Return the raw byte[] for the binary field.
float	getBoost() Returns the boost factor for hits for this field.
FieldInfo.IndexOptions	getIndexOptions()
boolean	getOmitNorms() True if norms are omitted for this indexed field
boolean	isBinary() True if the value of the field is stored as binary
boolean	isIndexed() True if the value of the field is to be indexed, so that it may be searched on.
boolean	isLazy() Indicates whether a Field is Lazy or not.
boolean	isStored() True if the value of the field is to be stored in the index for return with search hits.
boolean	isStoreOffsetWithTermVector() True if terms are stored as term vector together with their offsets (start and end positon in source text).
boolean	isStorePositionWithTermVector() True if terms are stored as term vector together with their token positions.
boolean	isTermVectorStored() True if the term or terms used to index this field are stored as a term vector, available from IndexReader.getTermFreqVector(int,String).
boolean	isTokenized() True if the value of the field should be tokenized as text prior to indexing.
String	name() Returns the name of the field as an interned string.
Reader	readerValue() The value of the field as a Reader, which can be used at index time to generate indexed tokens.
void	setBoost(float boost) Sets the boost factor hits on this field.
void	setIndexOptions(FieldInfo.IndexOptions indexOptions) Expert: If set, omit term freq, and optionally positions and payloads from postings for this field.
void	setOmitNorms(boolean omitNorms) Expert: If set, omit normalization factors associated with this indexed field.
String	stringValue() The value of the field as a String, or null.
TokenStream	tokenStreamValue() The TokenStream for this field to be used when indexing, or null.

Method Detail

setBoost

void setBoost(float boost)

Sets the boost factor hits on this field. This value will be multiplied into the score of all hits on this this field of this document.

The boost is multiplied by Document.getBoost() of the document containing this field. If a document has multiple fields with the same name, all such values are multiplied together. This product is then used to compute the norm factor for the field. By default, in the Similarity.computeNorm(String, FieldInvertState) method, the boost value is multiplied by the Similarity.lengthNorm(String, int) and then rounded by Similarity.encodeNormValue(float) before it is stored in the index. One should attempt to ensure that this product does not overflow the range of that encoding.

See Also:

Document.setBoost(float), Similarity.computeNorm(String, FieldInvertState), Similarity.encodeNormValue(float)

getBoost

float getBoost()

Returns the boost factor for hits for this field.

The default value is 1.0.

Note: this value is not stored directly with the document in the index. Documents returned from IndexReader.document(int) and Searcher.doc(int) may thus not have the same value present as when this field was indexed.

See Also:

setBoost(float)

name

String name()

Returns the name of the field as an interned string. For example "date", "title", "body", ...

stringValue

String stringValue()

The value of the field as a String, or null.

For indexing, if isStored()==true, the stringValue() will be used as the stored field value unless isBinary()==true, in which case getBinaryValue() will be used. If isIndexed()==true and isTokenized()==false, this String value will be indexed as a single token. If isIndexed()==true and isTokenized()==true, then tokenStreamValue() will be used to generate indexed tokens if not null, else readerValue() will be used to generate indexed tokens if not null, else stringValue() will be used to generate tokens.

readerValue

Reader readerValue()

The value of the field as a Reader, which can be used at index time to generate indexed tokens.

See Also:

stringValue()

tokenStreamValue

TokenStream tokenStreamValue()

The TokenStream for this field to be used when indexing, or null.

See Also:

stringValue()

isStored

boolean isStored()

True if the value of the field is to be stored in the index for return with search hits.

isIndexed

boolean isIndexed()

True if the value of the field is to be indexed, so that it may be searched on.

isTokenized

boolean isTokenized()

True if the value of the field should be tokenized as text prior to indexing. Un-tokenized fields are indexed as a single word and may not be Reader-valued.

isTermVectorStored

boolean isTermVectorStored()

True if the term or terms used to index this field are stored as a term vector, available from IndexReader.getTermFreqVector(int,String). These methods do not provide access to the original content of the field, only to terms used to index it. If the original content must be preserved, use the stored attribute instead.

See Also:

IndexReader.getTermFreqVector(int, String)

isStoreOffsetWithTermVector

boolean isStoreOffsetWithTermVector()

True if terms are stored as term vector together with their offsets (start and end positon in source text).

isStorePositionWithTermVector

boolean isStorePositionWithTermVector()

True if terms are stored as term vector together with their token positions.

isBinary

boolean isBinary()

True if the value of the field is stored as binary

getOmitNorms

boolean getOmitNorms()

True if norms are omitted for this indexed field

setOmitNorms

void setOmitNorms(boolean omitNorms)

Expert: If set, omit normalization factors associated with this indexed field. This effectively disables indexing boosts and length normalization for this field.

isLazy

boolean isLazy()

Indicates whether a Field is Lazy or not. The semantics of Lazy loading are such that if a Field is lazily loaded, retrieving it's values via stringValue() or getBinaryValue() is only valid as long as the IndexReader that retrieved the Document is still open.

Returns:

true if this field can be loaded lazily

getBinaryOffset

int getBinaryOffset()

Returns offset into byte[] segment that is used as value, if Field is not binary returned value is undefined

Returns:

index of the first character in byte[] segment that represents this Field value

getBinaryLength

int getBinaryLength()

Returns length of byte[] segment that is used as value, if Field is not binary returned value is undefined

Returns:

length of byte[] segment that represents this Field value

getBinaryValue

byte[] getBinaryValue()

Return the raw byte[] for the binary field. Note that you must also call getBinaryLength() and getBinaryOffset() to know which range of bytes in this returned array belong to the field.

Returns:

reference to the Field value as byte[].

getBinaryValue

byte[] getBinaryValue(byte[] result)

Return the raw byte[] for the binary field. Note that you must also call getBinaryLength() and getBinaryOffset() to know which range of bytes in this returned array belong to the field.

About reuse: if you pass in the result byte[] and it is used, likely the underlying implementation will hold onto this byte[] and return it in future calls to getBinaryValue(). So if you subsequently re-use the same byte[] elsewhere it will alter this Fieldable's value.

Parameters:

result - User defined buffer that will be used if possible. If this is null or not large enough, a new buffer is allocated

Returns:

reference to the Field value as byte[].

getIndexOptions

FieldInfo.IndexOptions getIndexOptions()

See Also:

setIndexOptions(org.apache.lucene.index.FieldInfo.IndexOptions)

setIndexOptions

void setIndexOptions(FieldInfo.IndexOptions indexOptions)

Expert: If set, omit term freq, and optionally positions and payloads from postings for this field.

NOTE: While this option reduces storage space required in the index, it also means any query requiring positional information, such as PhraseQuery or SpanQuery subclasses will silently fail to find results.