org.apache.lucene.search.function
Class FloatFieldSource

java.lang.Object
  org.apache.lucene.search.function.ValueSource
      org.apache.lucene.search.function.FieldCacheSource
          org.apache.lucene.search.function.FloatFieldSource

All Implemented Interfaces:

Serializable

public class FloatFieldSource
extends FieldCacheSource

Expert: obtains float field values from the FieldCache using getFloats() and makes those values available as other numeric types, casting as needed.

WARNING: The status of the search.function package is experimental. The APIs introduced here might change in the future and will not be supported anymore in such a case.

See Also:

for requirements on the field.

NOTE: with the switch in 2.9 to segment-based searching, if {@link #getValues} is invoked with a composite (multi-segment) reader, this can easily cause double RAM usage for the values in the FieldCache. It's best to switch your application to pass only atomic (single segment) readers to this API. Alternatively, for a short-term fix, you could wrap your ValueSource using {@link MultiValueSource}, which costs more CPU per lookup but will not consume double the FieldCache RAM.

, Serialized Form

Constructor Summary

FloatFieldSource(String field)
Create a cached float field source with default string-to-float parser.

FloatFieldSource(String field, FieldCache.FloatParser parser)
Create a cached float field source with a specific string-to-float parser.

Method Summary

boolean	cachedFieldSourceEquals(FieldCacheSource o) Check if equals to another FieldCacheSource, already knowing that cache and field are equal.
int	cachedFieldSourceHashCode() Return a hash code of a FieldCacheSource, without the hash-codes of the field and the cache (those are taken care of elsewhere).
String	description() description of field, used in explain()
DocValues	getCachedFieldValues(FieldCache cache, String field, IndexReader reader) Return cached DocValues for input field and reader.

Methods inherited from class org.apache.lucene.search.function.FieldCacheSource

equals, getValues, hashCode

Methods inherited from class org.apache.lucene.search.function.ValueSource

toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

FloatFieldSource

public FloatFieldSource(String field)

Create a cached float field source with default string-to-float parser.

FloatFieldSource

public FloatFieldSource(String field,
                        FieldCache.FloatParser parser)

Create a cached float field source with a specific string-to-float parser.

Method Detail

description

public String description()

Description copied from class: ValueSource

description of field, used in explain()

Overrides:

description in class FieldCacheSource

getCachedFieldValues

public DocValues getCachedFieldValues(FieldCache cache,
                                      String field,
                                      IndexReader reader)
                               throws IOException

Description copied from class: FieldCacheSource

Return cached DocValues for input field and reader.

Specified by:

getCachedFieldValues in class FieldCacheSource

Parameters:

cache - FieldCache so that values of a field are loaded once per reader (RAM allowing)

field - Field for which values are required.

Throws:

IOException

See Also:

ValueSource

cachedFieldSourceEquals

public boolean cachedFieldSourceEquals(FieldCacheSource o)

Description copied from class: FieldCacheSource

Check if equals to another FieldCacheSource, already knowing that cache and field are equal.

Specified by:

cachedFieldSourceEquals in class FieldCacheSource

See Also:

Object.equals(java.lang.Object)

cachedFieldSourceHashCode

public int cachedFieldSourceHashCode()

Description copied from class: FieldCacheSource

Return a hash code of a FieldCacheSource, without the hash-codes of the field and the cache (those are taken care of elsewhere).

Specified by:

cachedFieldSourceHashCode in class FieldCacheSource

See Also:

Object.hashCode()