Package org.apache.lucene.search

# Class LongValuesSource.ConstantLongValuesSource

java.lang.Object
org.apache.lucene.search.LongValuesSource
org.apache.lucene.search.LongValuesSource.ConstantLongValuesSource

All Implemented Interfaces:
  `SegmentCacheable`

Enclosing class:
  `LongValuesSource`

public static class LongValuesSource.ConstantLongValuesSource extends LongValuesSource
A ConstantLongValuesSource that always returns a constant value

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

## Nested Class Summary

## Nested classes/interfaces inherited from class org.apache.lucene.search.LongValuesSource

`LongValuesSource.ConstantLongValuesSource`

## Method Summary

Modifier and Type
Method
Description
`boolean`
`equals(Object o)`
`long`
`getValue()`
Get the constant value.
`LongValues`
`getValues(LeafReaderContext ctx, DoubleValues scores)`
Returns a `LongValues` instance for the passed-in LeafReaderContext and scores
`int`
`hashCode()`
`boolean`
`isCacheable(LeafReaderContext ctx)`
`boolean`
`needsScores()`
Return true if document scores are needed to calculate values
`LongValuesSource`
`rewrite(IndexSearcher searcher)`
Return a LongValuesSource specialised for the given IndexSearcher
`String`
`toString()`

### Methods inherited from class org.apache.lucene.search.LongValuesSource

`constant, fromIntField, fromLongField, getSortField, toDoubleValuesSource`

### Methods inherited from class java.lang.Object

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

## Method Details

### getValues

public LongValues getValues(LeafReaderContext ctx, DoubleValues scores) throws IOException
Description copied from class: `LongValuesSource`
Returns a `LongValues` instance for the passed-in LeafReaderContext and scores

If scores are not needed to calculate the values (ie `returns false`, callers may safely pass `null` for the `scores` parameter.

Specified by:
  `getValues` in class `LongValuesSource`
Throws:
  `IOException`

### isCacheable

public boolean isCacheable(LeafReaderContext ctx)

Returns:
  `true` if the object can be cached against a given leaf

### needsScores

public boolean needsScores()
Description copied from class: `LongValuesSource`
Return true if document scores are needed to calculate values

Specified by:
  `needsScores` in class `LongValuesSource`

### hashCode

public int hashCode()

Specified by:
  `hashCode` in class `LongValuesSource`

### equals

public boolean equals(Object o)

Specified by:
  `equals` in class `LongValuesSource`

### toString

public String toString()

Specified by:
  `toString` in class `LongValuesSource`

### rewrite

public LongValuesSource rewrite(IndexSearcher searcher) throws IOException
Description copied from class: `LongValuesSource`
Return a LongValuesSource specialised for the given IndexSearcher

Implementations should assume that this will only be called once. IndexSearcher-independent implementations can just return `this`

Specified by:
  `rewrite` in class `LongValuesSource`
Throws:
  `IOException`

### getValue

public long getValue()
Get the constant value.