java电子围栏

java版的电子围栏违规判断，经过测试，准确率接近百分之百，偏差在几米范围以内，

本工具类支持圆形，矩形，多边形，采用射线穿透算法，性能与准确率都有保障，实测判断多边形围栏，单线程执行百万次只需要十几秒，多线程只需要2秒

废话不说，直接上代码，先贴工具类代码

import com.core.entity.Point;

import java.util.Arrays;
import java.util.List;


public class GeofencingUtils {

    
    private static final double EARTH_RADIUS = 6378137.0;


    private static double rad(double d) {
        return d * Math.PI / 180.0;
    }

    
    public static boolean isInCircle(double radius, Point p1, Point p2) {
        double radLat1 = rad(p1.getLat());
        double radLat2 = rad(p2.getLat());
        double a = radLat1 - radLat2;
        double b = rad(p1.getLng()) - rad(p2.getLng());
        double s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2) +
                Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b / 2), 2)));
        s = s * EARTH_RADIUS;
        s = Math.round(s * 10000) / 10000;
        return !(s > radius);
    }

    
    public static boolean isInRectangleArea(double lng, double lat,  double minLng, double maxLng,
                                            double minLat, double maxLat) {
        if (isInRange(lat, minLat, maxLat)) {//如果在纬度的范围内
            if (minLng * maxLng > 0) {
                return isInRange(lng, minLng, maxLng);
            } else {
                if (Math.abs(minLng) + Math.abs(maxLng) < 180) {
                    return isInRange(lng, minLng, maxLng);
                } else {
                    double left = Math.max(minLng, maxLng);
                    double right = Math.min(minLng, maxLng);
                    return isInRange(lng, left, 180) || isInRange(lng, right, -180);
                }
            }
        } else {
            return false;
        }
    }

    
    public static boolean isInRectangleArea(Point point, Point[] gpsPoints) {
        if (gpsPoints.length != 4) {
            return false;
        }
        double[] lats = new double[4];
        double[] lngs = new double[4];
        for (int i = 0; i < gpsPoints.length; i++) {
            lats[i] = gpsPoints[i].getLat();
            lngs[i] = gpsPoints[i].getLng();
        }
        Arrays.sort(lats);
        Arrays.sort(lngs);
        return isInRectangleArea(point.getLat(), point.getLng(), lats[0], lats[3], lngs[0], lngs[3]);
    }


    
    public static boolean isInRange(double point, double left, double right) {
        return point >= Math.min(left, right) && point <= Math.max(left, right);
    }

    
    public static boolean isInPolygon(Point point, List pts) {

        int N = pts.size();
        boolean boundOrVertex = true;
        int intersectCount = 0;//交叉点数量
        double precision = 2e-10; //浮点类型计算时候与0比较时候的容差
        Point p1, p2;//临近顶点
        Point p = point; //当前点

        p1 = pts.get(0);
        for (int i = 1; i <= N; ++i) {
            if (p.equals(p1)) {
                return boundOrVertex;
            }

            p2 = pts.get(i % N);
            if (p.getLng() < Math.min(p1.getLng(), p2.getLng()) || p.getLng() > Math.max(p1.getLng(), p2.getLng())) {
                p1 = p2;
                continue;
            }

            //射线穿过算法
            if (p.getLng() > Math.min(p1.getLng(), p2.getLng()) && p.getLng() < Math.max(p1.getLng(), p2.getLng())) {
                if (p.getLat() <= Math.max(p1.getLat(), p2.getLat())) {
                    if (p1.getLng() == p2.getLng() && p.getLat() >= Math.min(p1.getLat(), p2.getLat())) {
                        return boundOrVertex;
                    }

                    if (p1.getLat() == p2.getLat()) {
                        if (p1.getLat() == p.getLat()) {
                            return boundOrVertex;
                        } else {
                            ++intersectCount;
                        }
                    } else {
                        double xinters = (p.getLng() - p1.getLng()) * (p2.getLat() - p1.getLat()) / (p2.getLng() - p1.getLng()) + p1.getLat();
                        if (Math.abs(p.getLat() - xinters) < precision) {
                            return boundOrVertex;
                        }

                        if (p.getLat() < xinters) {
                            ++intersectCount;
                        }
                    }
                }
            } else {
                if (p.getLng() == p2.getLng() && p.getLat() <= p2.getLat()) {
                    Point p3 = pts.get((i + 1) % N);
                    if (p.getLng() >= Math.min(p1.getLng(), p3.getLng()) && p.getLng() <= Math.max(p1.getLng(), p3.getLng())) {
                        ++intersectCount;
                    } else {
                        intersectCount += 2;
                    }
                }
            }
            p1 = p2;
        }
        return intersectCount % 2 != 0;
    }
}

再贴实体类

import lombok.Data;
import lombok.ToString;


@Data
@ToString
public class Point {
    
    private double lng;
    
    private double lat;

    public Point(double lng, double lat) {
        this.lng = lng;
        this.lat = lat;
    }
}

说明：用哪种坐标系不重要，但是围栏的经纬度与要判断的坐标点必须保持是同一种坐标系！！！！！！！！！！！