Package org.apache.lucene.search

# Class ScoreCachingWrappingScorer

java.lang.Object
org.apache.lucene.search.Scorable
org.apache.lucene.search.ScoreCachingWrappingScorer

public final class ScoreCachingWrappingScorer extends Scorable
A `Scorer` which wraps another scorer and caches the score of the current document. Successive calls to `score()` will return the same result and will not invoke the wrapped Scorer's score() method, unless the current document has changed.
This class might be useful due to the changes done to the `Collector` interface, in which the score is not computed for a document by default, only if the collector requests it. Some collectors may need to use the score in several places, however all they have in hand is a `Scorer` object, and might end up computing the score of a document more than once.

## Nested Class Summary

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

`Scorable.ChildScorable`

## Method Summary

Modifier and Type
Method
Description
`Collection<Scorable.ChildScorable>`
`getChildren()`
Returns child sub-scorers positioned on the current document
`float`
`score()`
Returns the score of the current document matching the query.
`void`
`setMinCompetitiveScore(float minScore)`
Optional method: Tell the scorer that its iterator may safely ignore all documents whose score is less than the given `minScore`.
`static LeafCollector`
`wrap(LeafCollector collector)`
Wrap the provided `LeafCollector` so that scores are computed lazily and cached if accessed multiple times.

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

`smoothingScore`

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

`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

## Method Details

### wrap

public static LeafCollector wrap(LeafCollector collector)
Wrap the provided `LeafCollector` so that scores are computed lazily and cached if accessed multiple times.

### score

public float score() throws IOException
Description copied from class: `Scorable`
Returns the score of the current document matching the query.

Specified by:
  `score` in class `Scorable`
Throws:
  `IOException`

### setMinCompetitiveScore

public void setMinCompetitiveScore(float minScore) throws IOException
Description copied from class: `Scorable`
Optional method: Tell the scorer that its iterator may safely ignore all documents whose score is less than the given `minScore`. This is a no-op by default.

This method may only be called from collectors that use `ScoreMode.TOP_SCORES`, and successive calls may only set increasing values of `minScore`.

Overrides:
  `setMinCompetitiveScore` in class `Scorable`
Throws:
  `IOException`

### getChildren

public Collection<Scorable.ChildScorable> getChildren()
Description copied from class: `Scorable`
Returns child sub-scorers positioned on the current document

Overrides:
  `getChildren` in class `Scorable`