给定一组经纬度如何判断某点是否在这组经纬度的范围之内（电子围栏实现代码）

方法一：

使用JTS Topology Suite 是 Java 的空间数据模型和空间分析操作的库，用于处理地理空间数据和进行空间分析。

1.1引入maven

<dependency><groupId>org.locationtech.jts</groupId><artifactId>jts-core</artifactId><version>1.18.0</version>
</dependency>

1.2:代码实现

@NoArgsConstructor
@AllArgsConstructor
@ApiModel(value = "坐标对象", description = "")
@Data
public class CoordinateGeog  implements Comparator<CoordinateGeog> {@ApiModelProperty("经度")private BigDecimal lng;@ApiModelProperty("纬度")private BigDecimal lat;@Overridepublic int compare(CoordinateGeog point1, CoordinateGeog point2) {double angle1 = Math.atan2(point1.getLat().subtract(lat).doubleValue(),point1.getLng().subtract(lng).doubleValue());double angle2 = Math.atan2(point2.getLat().subtract(lat).doubleValue(),point2.getLng().subtract(lng).doubleValue());return Double.compare(angle1, angle2);}
}

public class SpatialGeographyUtil {/*** 给定一组经纬度坐标集合，判断某点坐标是否在这组坐标所围的范围之内*/public static Polygon constructionScope( List<CoordinateGeog> innerCoordinateGeogs,GeometryFactory geometryFactory){List<Coordinate> coordinates = new ArrayList<>();innerCoordinateGeogs.forEach(i -> {Coordinate coordinate = new Coordinate(i.getLng().doubleValue(), i.getLat().doubleValue());coordinates.add(coordinate);});// 对坐标点进行极角排序sortCoordinatesByPolarAngle(coordinates);// 确保首尾坐标点相同，以确保闭合List<Coordinate> newCoordinates = endToEnd(coordinates);Coordinate[] coordinatesArray = newCoordinates.toArray(new Coordinate[newCoordinates.size()]);LinearRing linearRing = geometryFactory.createLinearRing(coordinatesArray);return geometryFactory.createPolygon(linearRing, null);}//按照参考点计算每个点相对于参考点的极角，然后进行排序public static void sortCoordinatesByPolarAngle(List<Coordinate> coordinates) {Coordinate reference = findReferencePointCoordinate(coordinates);coordinates.sort(Comparator.comparingDouble(point ->Math.atan2(point.y - reference.y, point.x - reference.x)));}//找到具有最小纬度的点public static Coordinate findReferencePointCoordinate(List<Coordinate> coordinates) {Coordinate reference = coordinates.get(0);for (Coordinate point : coordinates) {if (point.y < reference.y || (point.y == reference.y && point.x < reference.x)) {reference = point;}}return reference;}private static List<Coordinate> endToEnd(List<Coordinate> coordinates) {if (!coordinates.isEmpty()) {Coordinate first = coordinates.get(0);Coordinate last = coordinates.get(coordinates.size() - 1);if (!first.equals2D(last)) {coordinates.add(new Coordinate(first));}}return coordinates;}
}

方法二：.Path2D 是 Java 中用于创建和操作基本几何形状（如线条和曲线）的类。它是 Java 2D API 中的一部分，提供了一种可用于绘制 2D 图形的机制。

public class SpatialGeographyUtil {public static Path2D.Double createClosedPathForPolygon(List<CoordinateGeog> innerCoordinateGeogs) {// 确保首尾坐标点相同，以确保闭合List<CoordinateGeog> coordinateGeogs = ensurePolygonClosure(innerCoordinateGeogs);// 对坐标点进行极角排序List<CoordinateGeog> newCoordinateGeogs = sortPointsByPolarAngle(coordinateGeogs);Path2D.Double path = new Path2D.Double();for (int i = 0; i < newCoordinateGeogs.size() - 1; i++) {CoordinateGeog coords = newCoordinateGeogs.get(i);if (i == 0) {path.moveTo(coords.getLng().doubleValue(), coords.getLat().doubleValue());} else {path.lineTo(coords.getLng().doubleValue(), coords.getLat().doubleValue());}}path.closePath();return path;}public static Boolean checkPointInPathContainment(Path2D path, double lng, double lat) {Point2D point2Dr= new Point2D.Double(lng,lat);return path.contains(point2Dr);}public static List<CoordinateGeog> sortPointsByPolarAngle(List<CoordinateGeog> points) {// 找到最左下角的点作为参考点CoordinateGeog reference = findReferencePoint(points);// 使用极角比较器进行排序Collections.sort(points, new CoordinateGeog(reference.getLng(), reference.getLat()));return points;}//确保多边形闭合public static List<CoordinateGeog> ensurePolygonClosure(List<CoordinateGeog> polygon) {CoordinateGeog firstCoords = polygon.get(0);CoordinateGeog lastCoords = polygon.get(polygon.size() - 1);if (!firstCoords.getLng().equals(lastCoords.getLng()) || !firstCoords.getLat().equals(lastCoords.getLat())) {polygon.add(firstCoords); // 如果首尾不相连，将第一个点添加到最后}return polygon;}//集合中找到一个作为参考点的特定点public static CoordinateGeog findReferencePoint(List<CoordinateGeog> points) {CoordinateGeog reference = points.get(0);for (CoordinateGeog point : points) {if (point.getLat().compareTo(reference.getLat()) < 0 ||(point.getLat().compareTo(reference.getLat()) == 0 && point.getLng().compareTo(reference.getLng()) < 0)) {reference = point;}}return reference;}}

总结：