IndexSorter (Lucene 9.2.0 core API)

All Known Implementing Classes:

IndexSorter.DoubleSorter, IndexSorter.FloatSorter, IndexSorter.IntSorter, IndexSorter.LongSorter, IndexSorter.StringSorter
```
public interface IndexSorter
```
Handles how documents should be sorted in an index, both within a segment and between segments.
Implementers must provide the following methods: getDocComparator(LeafReader,int) - an object that determines how documents within a segment are to be sorted getComparableProviders(List) - an array of objects that return a sortable long value per document and segment getProviderName() - the SPI-registered name of a SortFieldProvider to serialize the sort
The companion SortFieldProvider should be registered with SPI via META-INF/services

Nested Class Summary

Nested Classes
Modifier and Type	Interface	Description
`static interface`	`IndexSorter.ComparableProvider`	Used for sorting documents across segments
`static interface`	`IndexSorter.DocComparator`	A comparator of doc IDs, used for sorting documents within a segment
`static class`	`IndexSorter.DoubleSorter`	Sorts documents based on double values from a NumericDocValues instance
`static class`	`IndexSorter.FloatSorter`	Sorts documents based on float values from a NumericDocValues instance
`static class`	`IndexSorter.IntSorter`	Sorts documents based on integer values from a NumericDocValues instance
`static class`	`IndexSorter.LongSorter`	Sorts documents based on long values from a NumericDocValues instance
`static interface`	`IndexSorter.NumericDocValuesProvider`	Provide a NumericDocValues instance for a LeafReader
`static interface`	`IndexSorter.SortedDocValuesProvider`	Provide a SortedDocValues instance for a LeafReader
`static class`	`IndexSorter.StringSorter`	Sorts documents based on terms from a SortedDocValues instance

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`IndexSorter.ComparableProvider[]`	`getComparableProviders(List<? extends LeafReader> readers)`	Get an array of `IndexSorter.ComparableProvider`, one per segment, for merge sorting documents in different segments
`IndexSorter.DocComparator`	`getDocComparator(LeafReader reader, int maxDoc)`	Get a comparator that determines the sort order of docs within a single Reader.
`String`	`getProviderName()`	The SPI-registered name of a `SortFieldProvider` that will deserialize the parent SortField

- Method Detail
  - getComparableProviders
```
IndexSorter.ComparableProvider[] getComparableProviders(List<? extends LeafReader> readers)
                                                 throws IOException
```
    Get an array of IndexSorter.ComparableProvider, one per segment, for merge sorting documents in different segments
    
    Parameters:
    
    readers - the readers to be merged
    
    Throws:
    
    IOException
  - getDocComparator
```
IndexSorter.DocComparator getDocComparator(LeafReader reader,
                                           int maxDoc)
                                    throws IOException
```
    Get a comparator that determines the sort order of docs within a single Reader.
    NB We cannot simply use the FieldComparator API because it requires docIDs to be sent in-order. The default implementations allocate array[maxDoc] to hold native values for comparison, but 1) they are transient (only alive while sorting this one segment) and 2) in the typical index sorting case, they are only used to sort newly flushed segments, which will be smaller than merged segments
    
    Parameters:
    
    reader - the Reader to sort
    
    maxDoc - the number of documents in the Reader
    
    Throws:
    
    IOException
  - getProviderName
```
String getProviderName()
```
    The SPI-registered name of a SortFieldProvider that will deserialize the parent SortField