Package org.apache.lucene.sandbox.search

## Class LatLonPointPrototypeQueries

- java.lang.Object
- - org.apache.lucene.sandbox.search.LatLonPointPrototypeQueries

-     public class LatLonPointPrototypeQueries
      extends Object

  Holder class for prototype sandboxed queries

  When the query graduates from sandbox, these static calls should be placed in `LatLonPoint`

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

- - ### Method Summary

    All Methods Static Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `static TopFieldDocs` | `nearest​(IndexSearcher searcher, String field, double latitude, double longitude, int n)` | Finds the `n` nearest indexed points to the provided point, according to Haversine distance.

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

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

- - ### Method Detail

    - #### nearest

          public static TopFieldDocs nearest​(IndexSearcher searcher,
                                             String field,
                                             double latitude,
                                             double longitude,
                                             int n)
                                      throws IOException

      Finds the `n` nearest indexed points to the provided point, according to Haversine distance.

      This is functionally equivalent to running `MatchAllDocsQuery` with a `LatLonDocValuesField.newDistanceSort(java.lang.String, double, double)`, but is far more efficient since it takes advantage of properties the indexed BKD tree. Currently this only works with `Lucene90PointsFormat` (used by the default codec). Multi-valued fields are currently not de-duplicated, so if a document had multiple instances of the specified field that make it into the top n, that document will appear more than once.

      Documents are ordered by ascending distance from the location. The value returned in `FieldDoc` for the hits contains a Double instance with the distance in meters.

      Parameters:
        `searcher` - IndexSearcher to find nearest points from.
        `field` - field name. must not be null.
        `latitude` - latitude at the center: must be within standard +/-90 coordinate bounds.
        `longitude` - longitude at the center: must be within standard +/-180 coordinate bounds.
        `n` - the number of nearest neighbors to retrieve.
      Returns:
        TopFieldDocs containing documents ordered by distance, where the field value for each `FieldDoc` is the distance in meters
      Throws:
        `IllegalArgumentException` - if the underlying PointValues is not a `Lucene60PointsReader` (this is a current limitation), or if `field` or `searcher` is null, or if `latitude`, `longitude` or `n` are out-of-bounds
        `IOException` - if an IOException occurs while finding the points.