Java导出Kml或Kmz格式文件

需求：根据前端传递的笛卡尔坐标转换为kml或者kmz格式的文件

 前端给的笛卡尔坐标数据格式为：

[{"x":-2385687.468728053,"y":5388713.58735659,"z":2431266.178004133},{"x":-2386487.889323949,"y":5388376.532927499,"z":2431227.9203221975},{"x":-2385720.8091358775,"y":5388914.668443492,"z":2430790.9295658045},{"x":-2386030.8053309857,"y":5388422.52348345,"z":2431572.274479368},{"x":-2386549.913805695,"y":5388583.616999787,"z":2430711.4885351057},{"x":-2385867.777372268,"y":5388687.89246894,"z":2431146.993799864}]

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解：

需要用到的依赖：

        <!--JavaAPIforKml依赖-->
        <dependency>
            <groupId>de.micromata.jak</groupId>
            <artifactId>JavaAPIforKml</artifactId>
            <version>2.2.0</version>
        </dependency>

因为这里是笛卡尔坐标，在kml文件内需要用到的是经纬度和海报高度，所以得先去把笛卡尔坐标转换成经纬度；

//笛卡尔坐标转经纬度
    public static String ECEFtoWGS84(double x, double y, double z) {
        double a, b, c, d;
        double Longitude;//经度
        double Latitude;//纬度
        double Altitude;//海拔高度
        double p, q;
        double N;
        a = 6378137.0;
        b = 6356752.31424518;
        c = Math.sqrt(((a * a) - (b * b)) / (a * a));
        d = Math.sqrt(((a * a) - (b * b)) / (b * b));
        p = Math.sqrt((x * x) + (y * y));
        q = Math.atan2((z * a), (p * b));
        Longitude = Math.atan2(y, x);
        Latitude = Math.atan2((z + (d * d) * b * Math.pow(Math.sin(q), 3)), (p - (c * c) * a * Math.pow(Math.cos(q), 3)));
        N = a / Math.sqrt(1 - ((c * c) * Math.pow(Math.sin(Latitude), 2)));
        Altitude = (p / Math.cos(Latitude)) - N;
        Longitude = Longitude * 180.0 / Math.PI;
        Latitude = Latitude * 180.0 / Math.PI;
        //默认海拔高度为0
        return Longitude + "," + Latitude + "," + Altitude + " "; //这里最后加了一个空,是为了方便数据一次性返回
    }

public Void getMarkerId(Integer id,Integer type,HttpServletResponse response) {
        Marker marker = this.getById(id);
        JSONArray jsonlist= JSON.parseArray(String.valueOf(marker.getGeom()));
        List<Coordinate> coordinates = new ArrayList<>();
        StringBuffer sb = new StringBuffer();
        for (Object list : jsonlist) {
            double x = Double.parseDouble(JSON.parseObject(String.valueOf(list)).getString("x"));
            double y= Double.parseDouble(JSON.parseObject(String.valueOf(list)).getString("y"));
            double z= Double.parseDouble(JSON.parseObject(String.valueOf(list)).getString("z"));
            String s = ECEFtoWGS84(x, y, z);
            sb.append(s);
            Coordinate coordinate = new Coordinate(s);
            coordinates.add(coordinate);
        }
        // 创建KML文档
        Kml kml = new Kml();
        Document document = kml.createAndSetDocument();

        // 创建Placemark
        Placemark placemark = document.createAndAddPlacemark();
        placemark.withName(marker.getTitle());

        //设置颜色
        Style andAddStyle = placemark.createAndAddStyle();
        LineStyle lineStyle = new LineStyle();
        lineStyle.setColor("80d94800");
        PolyStyle polyStyle = new PolyStyle();
        polyStyle.setColor("cc0050f0");
        andAddStyle.setLineStyle(lineStyle);
        andAddStyle.setPolyStyle(polyStyle);

        // 创建Polygon
        Polygon andSetPolygon = placemark.createAndSetPolygon();
        Boundary andSetOuterBoundaryIs = andSetPolygon.createAndSetOuterBoundaryIs();
        LinearRing linearRing = new LinearRing();
        linearRing.setCoordinates(coordinates);
        andSetOuterBoundaryIs.setLinearRing(linearRing);
        String today = DateUtil.today();
        String fileName = today + "_kml_file.kml";
        String fileKmzName = today + "_kml_file.kmz";
        try {
            if (type == 1){
                response.setHeader("Content-Disposition", "attachment;filename*=\""+fileName+"\"");
                response.setContentType("application/vnd.google-earth.kml+xml");
                OutputStream out = response.getOutputStream();
                kml.marshal(out);
                out.close();
            }else {
                response.setHeader("Content-Disposition", "attachment;filename=\""+fileKmzName+"\"");
                response.setContentType("application/vnd.google-earth.kmz");
                ByteArrayOutputStream kmlStream = new ByteArrayOutputStream();
                kml.marshal(kmlStream);
                ZipOutputStream zipStream = new ZipOutputStream(response.getOutputStream());
                ZipEntry zipEntry = new ZipEntry(fileName);
                zipStream.putNextEntry(zipEntry);
                zipStream.write(kmlStream.toByteArray());
                zipStream.closeEntry();
                zipStream.close();
            }
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        return null;
    }

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散会。