使用Criteria api查找半径内的坐标

import javax.persistence.EntityManager;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Predicate;
import javax.persistence.criteria.Root;

public class CoordinateSearch {
    private EntityManager entityManager;

    public List<Coordinate> searchCoordinatesWithinRadius(double centerLat, double centerLng, double radius) {
        CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
        CriteriaQuery<Coordinate> query = criteriaBuilder.createQuery(Coordinate.class);
        Root<Coordinate> root = query.from(Coordinate.class);

        double earthRadius = 6371; // 地球半径，单位为公里

        double latDiff = Math.toDegrees(radius / earthRadius);
        double lngDiff = Math.toDegrees(radius / (earthRadius * Math.cos(Math.toRadians(centerLat))));

        double minLat = centerLat - latDiff;
        double maxLat = centerLat + latDiff;
        double minLng = centerLng - lngDiff;
        double maxLng = centerLng + lngDiff;

        Predicate latPredicate = criteriaBuilder.between(root.get("latitude"), minLat, maxLat);
        Predicate lngPredicate = criteriaBuilder.between(root.get("longitude"), minLng, maxLng);

        query.select(root).where(criteriaBuilder.and(latPredicate, lngPredicate));

        return entityManager.createQuery(query).getResultList();
    }
}