java.lang.Object
- org.apache.lucene.search.function.ValueSource
- - org.apache.lucene.search.function.FieldCacheSource
  - - org.apache.lucene.search.function.ByteFieldSource

All Implemented Interfaces:

Serializable
```
public class ByteFieldSource
extends FieldCacheSource
```
Expert: obtains single byte field values from the FieldCache using getBytes() and makes those values available as other numeric types, casting as needed.

See Also:

for requirements on the field. NOTE: with the switch in 2.9 to segment-based searching, if 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., Serialized Form

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

Constructor Summary

Constructors
Constructor	Description
`ByteFieldSource(String field)`	Create a cached byte field source with default string-to-byte parser.
`ByteFieldSource(String field, FieldCache.ByteParser parser)`	Create a cached byte field source with a specific string-to-byte parser.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`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
  - ByteFieldSource
```
public ByteFieldSource(String field)
```
    Create a cached byte field source with default string-to-byte parser.
  - ByteFieldSource
```
public ByteFieldSource(String field,
                       FieldCache.ByteParser parser)
```
    Create a cached byte field source with a specific string-to-byte 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()

Class ByteFieldSource

Constructor Summary

Method Summary

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

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

Methods inherited from class java.lang.Object

Constructor Detail

ByteFieldSource

ByteFieldSource

Method Detail

description

getCachedFieldValues

cachedFieldSourceEquals

cachedFieldSourceHashCode