Java Code Examples for com.google.appengine.api.datastore.GeoPt#getLongitude()

/**
 * Builds a new Place document to insert in the Places index.
 * @param placeId      the identifier of the place in the database.
 * @param placeName    the name of the place.
 * @param placeAddress the address of the place.
 * @param location     the GPS location of the place, as a GeoPt.
 * @return the Place document created.
 */
public static Document buildDocument(
        final Long placeId, final String placeName,
        final String placeAddress, final GeoPt location) {
    GeoPoint geoPoint = new GeoPoint(location.getLatitude(),
            location.getLongitude());

    Document.Builder builder = Document.newBuilder()
            .addField(Field.newBuilder().setName("id")
                    .setText(placeId.toString()))
            .addField(Field.newBuilder().setName("name").setText(placeName))
            .addField(Field.newBuilder().setName("address")
                    .setText(placeAddress))
            .addField(Field.newBuilder().setName("place_location")
                    .setGeoPoint(geoPoint));

    // geo-location doesn't work under dev_server, so let's add another
    // field to use for retrieving documents
    if (environment.value() == Development) {
        builder.addField(Field.newBuilder().setName("value").setNumber(1));
    }

    return builder.build();
}
 

static Document buildDocument(
    String placeId, String placeName, String placeAddress, GeoPt location) {
  GeoPoint geoPoint = new GeoPoint(location.getLatitude(), location.getLongitude());

  Document.Builder builder = Document.newBuilder()
      .addField(Field.newBuilder().setName("id").setText(placeId))
      .addField(Field.newBuilder().setName("name").setText(placeName))
      .addField(Field.newBuilder().setName("address").setText(placeAddress))
      .addField(Field.newBuilder().setName("place_location").setGeoPoint(geoPoint));

  // geo-location doesn't work under dev_server, so let's add another
  // field to use for retrieving documents
  if (environment.value() == Development) {
    builder.addField(Field.newBuilder().setName("value").setNumber(1));
  }

  Document place = builder.build();

  return place;
}
 

/**
 * Returns the nearest places to the location of the user.
 * @param location the location of the user.
 * @param distanceInMeters the maximum distance to the user.
 * @param resultCount the maximum number of places returned.
 * @return List of up to resultCount places in the datastore ordered by
 *      the distance to the location parameter and less than
 *      distanceInMeters meters to the location parameter.
 */
public static List<PlaceInfo> getPlaces(final GeoPt location,
        final long distanceInMeters, final int resultCount) {

    // Optional: use memcache

    String geoPoint = "geopoint(" + location.getLatitude() + ", " + location
            .getLongitude()
            + ")";
    String locExpr = "distance(place_location, " + geoPoint + ")";

    // Build the SortOptions with 2 sort keys
    SortOptions sortOptions = SortOptions.newBuilder()
            .addSortExpression(SortExpression.newBuilder()
                    .setExpression(locExpr)
                    .setDirection(SortExpression.SortDirection.ASCENDING)
                    .setDefaultValueNumeric(distanceInMeters + 1))
            .setLimit(resultCount)
            .build();
    // Build the QueryOptions
    QueryOptions options = QueryOptions.newBuilder()
            .setSortOptions(sortOptions)
            .build();
    // Query string
    String searchQuery = "distance(place_location, " + geoPoint + ") < "
            + distanceInMeters;

    Query query = Query.newBuilder().setOptions(options).build(searchQuery);

    Results<ScoredDocument> results = getIndex().search(query);

    if (results.getNumberFound() == 0) {
        // geo-location doesn't work under dev_server
        if (environment.value() == Development) {
            // return all documents
            results = getIndex().search("value > 0");
        }
    }

    List<PlaceInfo> places = new ArrayList<>();

    for (ScoredDocument document : results) {
        if (places.size() >= resultCount) {
            break;
        }

        GeoPoint p = document.getOnlyField("place_location").getGeoPoint();

        PlaceInfo place = new PlaceInfo();
        place.setPlaceId(Long.valueOf(document.getOnlyField("id")
                .getText()));
        place.setName(document.getOnlyField("name").getText());
        place.setAddress(document.getOnlyField("address").getText());

        place.setLocation(new GeoPt((float) p.getLatitude(),
                (float) p.getLongitude()));

        // GeoPoints are not implemented on dev server and latitude and
        // longitude are set to zero
        // But since those are doubles let's play safe
        // and use double comparison with epsilon set to EPSILON
        if (Math.abs(p.getLatitude()) <= EPSILON
                && Math.abs(p.getLongitude()) <= EPSILON) {
            // set a fake distance of 5+ km
            place.setDistanceInKilometers(FAKE_DISTANCE_FOR_DEV + places
                    .size());
        } else {
            double distance = distanceInMeters / METERS_IN_KILOMETER;
            try {
                distance = getDistanceInKm(
                        p.getLatitude(), p.getLongitude(),
                        location.getLatitude(),
                        location.getLongitude());
            } catch (Exception e) {
                LOG.warning("Exception when calculating a distance: " + e
                        .getMessage());
            }

            place.setDistanceInKilometers(distance);
        }

        places.add(place);
    }
    return places;
}
 

static List<PlaceInfo> getPlaces(GeoPt location, long distanceInMeters, int resultCount) {

    // TODO(user): Use memcache

    String geoPoint = "geopoint(" + location.getLatitude() + ", " + location.getLongitude() + ")";

    String query = "distance(place_location, " + geoPoint + ") < " + distanceInMeters;
    String locExpr = "distance(place_location, " + geoPoint + ")";

    SortExpression sortExpr = SortExpression.newBuilder()
        .setExpression(locExpr)
        .setDirection(SortExpression.SortDirection.ASCENDING)
        .setDefaultValueNumeric(distanceInMeters + 1)
        .build();
    Query searchQuery = Query.newBuilder().setOptions(QueryOptions.newBuilder()
        .setSortOptions(SortOptions.newBuilder().addSortExpression(sortExpr))).build(query);
    Results<ScoredDocument> results = getIndex().search(searchQuery);

    if (results.getNumberFound() == 0) {
      // geo-location doesn't work under dev_server
      if (environment.value() == Development) {
        // return all documents
        results = getIndex().search("value > 0");
      }
    }

    List<PlaceInfo> places = new ArrayList<PlaceInfo>();

    for (ScoredDocument document : results) {
      if (places.size() >= resultCount) {
        break;
      }

      GeoPoint p = document.getOnlyField("place_location").getGeoPoint();

      PlaceInfo place = new PlaceInfo();
      place.setplaceID(document.getOnlyField("id").getText());
      place.setName(document.getOnlyField("name").getText());
      place.setAddress(document.getOnlyField("address").getText());

      place.setLocation(new GeoPt((float) p.getLatitude(), (float) p.getLongitude()));

      // GeoPoints are not implemented on dev server and latitude and longitude are set to zero
      // But since those are doubles let's play safe
      // and use double comparison with epsilon set to 0.0001
      if (Math.abs(p.getLatitude()) <= 0.0001 && Math.abs(p.getLongitude()) <= 0.0001) {
        // set a fake distance of 5+ km
        place.setDistanceInKilometers(5 + places.size());
      } else {
        double distance = distanceInMeters / 1000;
        try {
          distance = getDistanceInKm(
              p.getLatitude(), p.getLongitude(), location.getLatitude(), location.getLongitude());
        } catch (Exception e) {
          log.warning("Exception when calculating a distance: " + e.getMessage());
        }

        place.setDistanceInKilometers(distance);
      }

      places.add(place);
    }

    return places;
  }