https://lucene.apache.org/lucene-parent/lucene-core: Apache Lucene Java Core (The Apache Software Foundation) 
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 * (the "License"); you may not use this file except in compliance with
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 *     http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.lucene.document;

import org.apache.lucene.geo.XYCircle;
import org.apache.lucene.geo.XYEncodingUtils;
import org.apache.lucene.geo.XYPolygon;
import org.apache.lucene.geo.XYRectangle;
import org.apache.lucene.index.DocValuesType;
import org.apache.lucene.index.FieldInfo;
import org.apache.lucene.search.FieldDoc;
import org.apache.lucene.search.IndexOrDocValuesQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.SortField;



An per-document location field.


Sorting by distance is efficient. Multiple values for the same field in one document
is allowed. 


This field defines static factory methods for common operations:



 If you also need query operations, you should add a separate XYPointField instance. If you also need to store the value, you should add a separate StoredField instance. 
See Also:
/** 
 * An per-document location field.
 * <p>
 * Sorting by distance is efficient. Multiple values for the same field in one document
 * is allowed. 
 * <p>
 * This field defines static factory methods for common operations:
 * <ul>
 *   <li>{@link #newDistanceSort newDistanceSort()} for ordering documents by distance from a specified location.
 * </ul>
 * <p>
 * If you also need query operations, you should add a separate {@link XYPointField} instance.
 * If you also need to store the value, you should add a separate {@link StoredField} instance.
 *
 * @see XYPointField
 */
public class XYDocValuesField extends Field {

  
Type for a XYDocValuesField


Each value stores a 64-bit long where the upper 32 bits are the encoded x value,
and the lower 32 bits are the encoded y value.

See Also:
  • decode.decode(int)
/**
   * Type for a XYDocValuesField
   * <p>
   * Each value stores a 64-bit long where the upper 32 bits are the encoded x value,
   * and the lower 32 bits are the encoded y value.
   * @see org.apache.lucene.geo.XYEncodingUtils#decode(int)
   */
  public static final FieldType TYPE = new FieldType();
  static {
    TYPE.setDocValuesType(DocValuesType.SORTED_NUMERIC);
    TYPE.freeze();
  }

  
Creates a new XYDocValuesField with the specified x and y

Params:
  • name – field name
  • x – x value.
  • y – y values.
Throws:
/**
   * Creates a new XYDocValuesField with the specified x and y
   * @param name field name
   * @param x x value.
   * @param y y values.
   * @throws IllegalArgumentException if the field name is null or x or y are infinite or NaN.
   */
  public XYDocValuesField(String name, float x, float y) {
    super(name, TYPE);
    setLocationValue(x, y);
  }
  
  
Change the values of this field

Params:
  • x – x value.
  • y – y value.
Throws:
/**
   * Change the values of this field
   * @param x x value.
   * @param y y value.
   * @throws IllegalArgumentException  if x or y are infinite or NaN.
   */
  public void setLocationValue(float x, float y) {
    int xEncoded = XYEncodingUtils.encode(x);
    int yEncoded = XYEncodingUtils.encode(y);
    fieldsData = Long.valueOf((((long) xEncoded) << 32) | (yEncoded & 0xFFFFFFFFL));
  }

  
helper: checks a fieldinfo and throws exception if its definitely not a XYDocValuesField 
/** helper: checks a fieldinfo and throws exception if its definitely not a XYDocValuesField */
  static void checkCompatible(FieldInfo fieldInfo) {
    // dv properties could be "unset", if you e.g. used only StoredField with this same name in the segment.
    if (fieldInfo.getDocValuesType() != DocValuesType.NONE && fieldInfo.getDocValuesType() != TYPE.docValuesType()) {
      throw new IllegalArgumentException("field=\"" + fieldInfo.name + "\" was indexed with docValuesType=" + fieldInfo.getDocValuesType() + 
                                         " but this type has docValuesType=" + TYPE.docValuesType() + 
                                         ", is the field really a XYDocValuesField?");
    }
  }
  
  @Override
  public String toString() {
    StringBuilder result = new StringBuilder();
    result.append(getClass().getSimpleName());
    result.append(" <");
    result.append(name);
    result.append(':');

    long currentValue = (Long)fieldsData;
    result.append(XYEncodingUtils.decode((int)(currentValue >> 32)));
    result.append(',');
    result.append(XYEncodingUtils.decode((int)(currentValue & 0xFFFFFFFF)));

    result.append('>');
    return result.toString();
  }

  
Creates a SortField for sorting by distance from a location.

 This sort orders documents by ascending distance from the location. The value returned in FieldDoc for the hits contains a Double instance with the distance in meters. 
 If a document is missing the field, then by default it is treated as having Double.POSITIVE_INFINITY distance (missing values sort last). 

If a document contains multiple values for the field, the closest distance to the location is used.

Params:
  • field – field name. must not be null.
  • x – x at the center.
  • y – y at the center.
Throws:
Returns:SortField ordering documents by distance
/**
   * Creates a SortField for sorting by distance from a location.
   * <p>
   * This sort orders documents by ascending distance from the location. The value returned in {@link FieldDoc} for
   * the hits contains a Double instance with the distance in meters.
   * <p>
   * If a document is missing the field, then by default it is treated as having {@link Double#POSITIVE_INFINITY} distance
   * (missing values sort last).
   * <p>
   * If a document contains multiple values for the field, the <i>closest</i> distance to the location is used.
   * 
   * @param field field name. must not be null.
   * @param x x at the center.
   * @param y y at the center.
   * @return SortField ordering documents by distance
   * @throws IllegalArgumentException if {@code field} is null or location has invalid coordinates.
   */
  public static SortField newDistanceSort(String field, float x, float y) {
    return new XYPointSortField(field, x, y);
  }

  
Create a query for matching a bounding box using doc values. This query is usually slow as it does not use an index structure and needs to verify documents one-by-one in order to know whether they match. It is best used wrapped in an IndexOrDocValuesQuery alongside a XYPointField.newBoxQuery. 
/**
   * Create a query for matching a bounding box using doc values.
   * This query is usually slow as it does not use an index structure and needs
   * to verify documents one-by-one in order to know whether they match. It is
   * best used wrapped in an {@link IndexOrDocValuesQuery} alongside a
   * {@link XYPointField#newBoxQuery}.
   */
  public static Query newSlowBoxQuery(String field, float minX, float maxX, float minY, float maxY) {
    XYRectangle rectangle = new XYRectangle(minX, maxX, minY, maxY);
    return new XYDocValuesPointInGeometryQuery(field, rectangle);
  }

  
Create a query for matching points within the specified distance of the supplied location. This query is usually slow as it does not use an index structure and needs to verify documents one-by-one in order to know whether they match. It is best used wrapped in an IndexOrDocValuesQuery alongside a XYPointField.newDistanceQuery. 
Params:
  • field – field name. must not be null.
  • x – x at the center.
  • y – y at the center: must be within standard +/-180 coordinate bounds.
  • radius – maximum distance from the center in cartesian distance: must be non-negative and finite.
Throws:
Returns:query matching points within this distance
/**
   * Create a query for matching points within the specified distance of the supplied location.
   * This query is usually slow as it does not use an index structure and needs
   * to verify documents one-by-one in order to know whether they match. It is
   * best used wrapped in an {@link IndexOrDocValuesQuery} alongside a
   * {@link XYPointField#newDistanceQuery}.
   * @param field field name. must not be null.
   * @param x x at the center.
   * @param y y at the center: must be within standard +/-180 coordinate bounds.
   * @param radius maximum distance from the center in cartesian distance: must be non-negative and finite.
   * @return query matching points within this distance
   * @throws IllegalArgumentException if {@code field} is null, location has invalid coordinates, or radius is invalid.
   */
  public static Query newSlowDistanceQuery(String field, float x, float y, float radius) {
    XYCircle circle = new XYCircle(x, y, radius);
    return new XYDocValuesPointInGeometryQuery(field, circle);
  }

  
Create a query for matching points within the supplied polygons. This query is usually slow as it does not use an index structure and needs to verify documents one-by-one in order to know whether they match. It is best used wrapped in an IndexOrDocValuesQuery alongside a XYPointField.newPolygonQuery(String, XYPolygon...). 
Params:
  • field – field name. must not be null.
  • polygons – array of polygons. must not be null or empty.
Throws:
Returns:query matching points within the given polygons.
/**
   * Create a query for matching points within the supplied polygons.
   * This query is usually slow as it does not use an index structure and needs
   * to verify documents one-by-one in order to know whether they match. It is
   * best used wrapped in an {@link IndexOrDocValuesQuery} alongside a
   * {@link XYPointField#newPolygonQuery(String, XYPolygon...)}.
   * @param field field name. must not be null.
   * @param polygons array of polygons. must not be null or empty.
   * @return query matching points within the given polygons.
   * @throws IllegalArgumentException if {@code field} is null or polygons is empty or contain a null polygon.
   */
  public static Query newSlowPolygonQuery(String field, XYPolygon... polygons) {
    return new XYDocValuesPointInGeometryQuery(field, polygons);
  }
}