Interface IFieldCache

Expert: Maintains caches of term values.

Created: May 19, 2004 11:13:14 AM

Note

This API is for internal purposes only and might change in incompatible ways in the next release.

@since lucene 1.4
Namespace: Lucene.Net.Search
Assembly: Lucene.Net.dll
Syntax
public interface IFieldCache

Properties

InfoStream

If non-null, FieldCacheImpl will warn whenever entries are created that are not sane according to FieldCacheSanityChecker.

Declaration
TextWriter InfoStream { get; set; }
Property Value
Type Description
TextWriter
See Also

Methods

GetBytes(AtomicReader, string, IByteParser, bool)

Checks the internal cache for an appropriate entry, and if none is found, reads the terms in field as bytes and returns an array of size reader.MaxDoc of the value each document has in the given field.

Declaration
[Obsolete("(4.4) Index as a numeric field using Int32Field and then use GetInt32s(AtomicReader, string, bool) instead.")]
FieldCache.Bytes GetBytes(AtomicReader reader, string field, FieldCache.IByteParser parser, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader

Used to get field values.
string field

Which field contains the bytes.
FieldCache.IByteParser parser

Computes byte for string values.
bool setDocsWithField

If true then GetDocsWithField(AtomicReader, string) will also be computed and stored in the IFieldCache.
Returns
Type Description
FieldCache.Bytes

The values in the given field for each document.
Exceptions
Type Condition
IOException

If any error occurs.
See Also

GetBytes(AtomicReader, string, bool)

Checks the internal cache for an appropriate entry, and if none is found, reads the terms in field as a single byte and returns an array of size reader.MaxDoc of the value each document has in the given field.

Declaration
[Obsolete("(4.4) Index as a numeric field using Int32Field and then use GetInt32s(AtomicReader, string, bool) instead.")]
FieldCache.Bytes GetBytes(AtomicReader reader, string field, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader

Used to get field values.
string field

Which field contains the single byte values.
bool setDocsWithField

If true then GetDocsWithField(AtomicReader, string) will also be computed and stored in the IFieldCache.
Returns
Type Description
FieldCache.Bytes

The values in the given field for each document.
Exceptions
Type Condition
IOException

If any error occurs.
See Also

GetCacheEntries()

EXPERT: Generates an array of FieldCache.CacheEntry objects representing all items currently in the IFieldCache.

NOTE: These FieldCache.CacheEntry objects maintain a strong reference to the Cached Values. Maintaining references to a FieldCache.CacheEntry the AtomicReader associated with it has garbage collected will prevent the Value itself from being garbage collected when the Cache drops the WeakReference.

Note

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

Declaration
FieldCache.CacheEntry[] GetCacheEntries()
Returns
Type Description
CacheEntry[]
See Also

GetDocTermOrds(AtomicReader, string)

Checks the internal cache for an appropriate entry, and if none is found, reads the term values in field and returns a SortedSetDocValues instance, providing a method to retrieve the terms (as ords) per document.

Declaration
SortedSetDocValues GetDocTermOrds(AtomicReader reader, string field)
Parameters
Type Name Description
AtomicReader reader

Used to build a SortedSetDocValues instance
string field

Which field contains the strings.
Returns
Type Description
SortedSetDocValues

a SortedSetDocValues instance
Exceptions
Type Condition
IOException

If any error occurs.
See Also

GetDocsWithField(AtomicReader, string)

Checks the internal cache for an appropriate entry, and if none is found, reads the terms in field and returns a bit set at the size of reader.MaxDoc, with turned on bits for each docid that does have a value for this field.

Declaration
IBits GetDocsWithField(AtomicReader reader, string field)
Parameters
Type Name Description
AtomicReader reader
string field
Returns
Type Description
IBits
See Also

GetDoubles(AtomicReader, string, IDoubleParser, bool)

Returns a FieldCache.Doubles over the values found in documents in the given field. If the field was indexed as NumericDocValuesField, it simply uses GetNumericDocValues(string) to read the values. Otherwise, it checks the internal cache for an appropriate entry, and if none is found, reads the terms in field as doubles and returns an array of size reader.MaxDoc of the value each document has in the given field.

Declaration
FieldCache.Doubles GetDoubles(AtomicReader reader, string field, FieldCache.IDoubleParser parser, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader

Used to get field values.
string field

Which field contains the doubles.
FieldCache.IDoubleParser parser

Computes double for string values. May be null if the requested field was indexed as NumericDocValuesField or DoubleField.
bool setDocsWithField

If true then GetDocsWithField(AtomicReader, string) will also be computed and stored in the IFieldCache.
Returns
Type Description
FieldCache.Doubles

The values in the given field for each document.
Exceptions
Type Condition
IOException

If any error occurs.
See Also

GetDoubles(AtomicReader, string, bool)

Returns a FieldCache.Doubles over the values found in documents in the given field.

Declaration
FieldCache.Doubles GetDoubles(AtomicReader reader, string field, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader
string field
bool setDocsWithField
Returns
Type Description
FieldCache.Doubles
See Also

GetInt16s(AtomicReader, string, IInt16Parser, bool)

Checks the internal cache for an appropriate entry, and if none is found, reads the terms in field as shorts and returns an array of size reader.MaxDoc of the value each document has in the given field.

NOTE: this was getShorts() in Lucene
Declaration
[Obsolete("(4.4) Index as a numeric field using Int32Field and then use GetInt32s(AtomicReader, string, bool) instead.")]
FieldCache.Int16s GetInt16s(AtomicReader reader, string field, FieldCache.IInt16Parser parser, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader

Used to get field values.
string field

Which field contains the shorts.
FieldCache.IInt16Parser parser

Computes short for string values.
bool setDocsWithField

If true then GetDocsWithField(AtomicReader, string) will also be computed and stored in the IFieldCache.
Returns
Type Description
FieldCache.Int16s

The values in the given field for each document.
Exceptions
Type Condition
IOException

If any error occurs.
See Also

GetInt16s(AtomicReader, string, bool)

Checks the internal cache for an appropriate entry, and if none is found, reads the terms in field as shorts and returns an array of size reader.MaxDoc of the value each document has in the given field.

NOTE: this was getShorts() in Lucene
Declaration
[Obsolete("(4.4) Index as a numeric field using Int32Field and then use GetInt32s(AtomicReader, string, bool) instead.")]
FieldCache.Int16s GetInt16s(AtomicReader reader, string field, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader

Used to get field values.
string field

Which field contains the shorts.
bool setDocsWithField

If true then GetDocsWithField(AtomicReader, string) will also be computed and stored in the IFieldCache.
Returns
Type Description
FieldCache.Int16s

The values in the given field for each document.
Exceptions
Type Condition
IOException

If any error occurs.
See Also

GetInt32s(AtomicReader, string, IInt32Parser, bool)

Returns an FieldCache.Int32s over the values found in documents in the given field. If the field was indexed as NumericDocValuesField, it simply uses GetNumericDocValues(string) to read the values. Otherwise, it checks the internal cache for an appropriate entry, and if none is found, reads the terms in field as ints and returns an array of size reader.MaxDoc of the value each document has in the given field.

NOTE: this was getInts() in Lucene
Declaration
FieldCache.Int32s GetInt32s(AtomicReader reader, string field, FieldCache.IInt32Parser parser, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader

Used to get field values.
string field

Which field contains the ints.
FieldCache.IInt32Parser parser

Computes int for string values. May be null if the requested field was indexed as NumericDocValuesField or Int32Field.
bool setDocsWithField

If true then GetDocsWithField(AtomicReader, string) will also be computed and stored in the IFieldCache.
Returns
Type Description
FieldCache.Int32s

The values in the given field for each document.
Exceptions
Type Condition
IOException

If any error occurs.
See Also

GetInt32s(AtomicReader, string, bool)

Returns an FieldCache.Int32s over the values found in documents in the given field.

NOTE: this was getInts() in Lucene
Declaration
FieldCache.Int32s GetInt32s(AtomicReader reader, string field, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader
string field
bool setDocsWithField
Returns
Type Description
FieldCache.Int32s
See Also

GetInt64s(AtomicReader, string, IInt64Parser, bool)

Returns a FieldCache.Int64s over the values found in documents in the given field. If the field was indexed as NumericDocValuesField, it simply uses GetNumericDocValues(string) to read the values. Otherwise, it checks the internal cache for an appropriate entry, and if none is found, reads the terms in field as longs and returns an array of size reader.MaxDoc of the value each document has in the given field.

NOTE: this was getLongs() in Lucene
Declaration
FieldCache.Int64s GetInt64s(AtomicReader reader, string field, FieldCache.IInt64Parser parser, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader

Used to get field values.
string field

Which field contains the longs.
FieldCache.IInt64Parser parser

Computes long for string values. May be null if the requested field was indexed as NumericDocValuesField or Int64Field.
bool setDocsWithField

If true then GetDocsWithField(AtomicReader, string) will also be computed and stored in the IFieldCache.
Returns
Type Description
FieldCache.Int64s

The values in the given field for each document.
Exceptions
Type Condition
IOException

If any error occurs.
See Also

GetInt64s(AtomicReader, string, bool)

Returns a FieldCache.Int64s over the values found in documents in the given field.

NOTE: this was getLongs() in Lucene
Declaration
FieldCache.Int64s GetInt64s(AtomicReader reader, string field, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader
string field
bool setDocsWithField
Returns
Type Description
FieldCache.Int64s
See Also

GetSingles(AtomicReader, string, ISingleParser, bool)

Returns a FieldCache.Singles over the values found in documents in the given field. If the field was indexed as NumericDocValuesField, it simply uses GetNumericDocValues(string) to read the values. Otherwise, it checks the internal cache for an appropriate entry, and if none is found, reads the terms in field as floats and returns an array of size reader.MaxDoc of the value each document has in the given field.

NOTE: this was getFloats() in Lucene
Declaration
FieldCache.Singles GetSingles(AtomicReader reader, string field, FieldCache.ISingleParser parser, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader

Used to get field values.
string field

Which field contains the floats.
FieldCache.ISingleParser parser

Computes float for string values. May be null if the requested field was indexed as NumericDocValuesField or SingleField.
bool setDocsWithField

If true then GetDocsWithField(AtomicReader, string) will also be computed and stored in the IFieldCache.
Returns
Type Description
FieldCache.Singles

The values in the given field for each document.
Exceptions
Type Condition
IOException

If any error occurs.
See Also

GetSingles(AtomicReader, string, bool)

Returns a FieldCache.Singles over the values found in documents in the given field.

NOTE: this was getFloats() in Lucene
Declaration
FieldCache.Singles GetSingles(AtomicReader reader, string field, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader
string field
bool setDocsWithField
Returns
Type Description
FieldCache.Singles
See Also

GetTerms(AtomicReader, string, bool)

Checks the internal cache for an appropriate entry, and if none is found, reads the term values in field and returns a BinaryDocValues instance, providing a method to retrieve the term (as a BytesRef) per document.

Declaration
BinaryDocValues GetTerms(AtomicReader reader, string field, bool setDocsWithField)
Parameters
Type Name Description
AtomicReader reader

Used to get field values.
string field

Which field contains the strings.
bool setDocsWithField

If true then GetDocsWithField(AtomicReader, string) will also be computed and stored in the IFieldCache.
Returns
Type Description
BinaryDocValues

The values in the given field for each document.
Exceptions
Type Condition
IOException

If any error occurs.
See Also

GetTerms(AtomicReader, string, bool, float)

Expert: just like GetTerms(AtomicReader, string, bool), but you can specify whether more RAM should be consumed in exchange for faster lookups (default is "true"). Note that the first call for a given reader and field "wins", subsequent calls will share the same cache entry.

Declaration
BinaryDocValues GetTerms(AtomicReader reader, string field, bool setDocsWithField, float acceptableOverheadRatio)
Parameters
Type Name Description
AtomicReader reader
string field
bool setDocsWithField
float acceptableOverheadRatio
Returns
Type Description
BinaryDocValues
See Also

GetTermsIndex(AtomicReader, string)

Checks the internal cache for an appropriate entry, and if none is found, reads the term values in field and returns a SortedDocValues instance, providing methods to retrieve sort ordinals and terms (as a BytesRef) per document.

Declaration
SortedDocValues GetTermsIndex(AtomicReader reader, string field)
Parameters
Type Name Description
AtomicReader reader

Used to get field values.
string field

Which field contains the strings.
Returns
Type Description
SortedDocValues

The values in the given field for each document.
Exceptions
Type Condition
IOException

If any error occurs.
See Also

GetTermsIndex(AtomicReader, string, float)

Expert: just like GetTermsIndex(AtomicReader, string), but you can specify whether more RAM should be consumed in exchange for faster lookups (default is "true"). Note that the first call for a given reader and field "wins", subsequent calls will share the same cache entry.

Declaration
SortedDocValues GetTermsIndex(AtomicReader reader, string field, float acceptableOverheadRatio)
Parameters
Type Name Description
AtomicReader reader
string field
float acceptableOverheadRatio
Returns
Type Description
SortedDocValues
See Also

PurgeAllCaches()

EXPERT: Instructs the FieldCache to forcibly expunge all entries from the underlying caches. This is intended only to be used for test methods as a way to ensure a known base state of the Cache (with out needing to rely on GC to free WeakReferences). It should not be relied on for "Cache maintenance" in general application code.

Note

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

Declaration
void PurgeAllCaches()
See Also

PurgeByCacheKey(object)

Expert: drops all cache entries associated with this reader CoreCacheKey. NOTE: this cache key must precisely match the reader that the cache entry is keyed on. If you pass a top-level reader, it usually will have no effect as Lucene now caches at the segment reader level.

Declaration
void PurgeByCacheKey(object coreCacheKey)
Parameters
Type Name Description
object coreCacheKey
See Also

See Also