http://stackoverflow.com/questions/36415307

CensusSectorGroup findClosestNEQuadrant(BigDecimal latitude, BigDecimal longitude) {
    String whereClause = 'WHERE SG.latitude >= :latitude AND SG.longitude >= :longitude'
    return runQuadrantQueryWith(whereClause, latitude, longitude)
}

private CensusSectorGroup runQuadrantQueryWith (String whereClause, BigDecimal latitude, BigDecimal longitude) {
    String jpql = MAIN_QUERY + whereClause + ORDER_BY
    Query query = em.createQuery(jpql)
    query.setParameter("latitude", latitude)
    query.setParameter("longitude", longitude)
    query.setMaxResults(MAX_RESULTS_QTT)
    List<Quadrant> quadrant= query.getResultList()
    return quadrant?.get(0)?.group
}

/* CONSTANTS */
private static final int MAX_RESULTS_QTT = 1
private static final String MAIN_QUERY = "SELECT SG," +
                        "111.045 * " +
                        "FUNC('DEGREES'," +
                        "FUNC('ACOS'," +
                        "FUNC('COS'," +
                        "FUNC('RADIANS',:latitude)" +
                        ") * FUNC('COS'," +
                        "FUNC('RADIANS',SG.lat_centroid)" +
                        ") * FUNC('COS'," +
                        "FUNC('RADIANS',:longitude) - FUNC('RADIANS',SG.long_centroid)" +
                        ") + FUNC('SIN'," +
                        "FUNC('RADIANS',:latitude)" +
                        ") * FUNC('SIN'," +
                        "FUNC('RADIANS',SG.lat_centroid)))" +
                        ") AS distance_in_km" +
                        "FROM CensusSectorGroup SG"
private static final String ORDER_BY = "ORDER BY distance_in_km ASC"