在java中返回GeoJSON对象

import org.geotools.data.simple.SimpleFeatureCollection;
import org.geotools.geojson.feature.FeatureJSON;
import org.geotools.geojson.geom.GeometryJSON;
import org.geotools.geometry.jts.JTSFactoryFinder;
import org.locationtech.jts.geom.GeometryFactory;
import org.locationtech.jts.geom.Point;

import java.io.StringWriter;

public class GeoJSONExample {
    public static void main(String[] args) throws Exception {
        // 创建一个GeometryFactory，用于创建地理要素
        GeometryFactory geometryFactory = JTSFactoryFinder.getGeometryFactory();

        // 创建一个点
        Point point = geometryFactory.createPoint(new Coordinate(1, 1));

        // 创建一个SimpleFeatureCollection，包含该点
        SimpleFeatureCollection featureCollection = FeatureCollections.newCollection();
        featureCollection.add(SimpleFeatureBuilder.build(point, null));

        // 创建一个StringWriter，用于将GeoJSON写入字符串
        StringWriter writer = new StringWriter();

        // 创建一个FeatureJSON，用于将SimpleFeatureCollection转换为GeoJSON
        FeatureJSON featureJSON = new FeatureJSON(new GeometryJSON());

        // 将SimpleFeatureCollection转换为GeoJSON，并写入字符串
        featureJSON.writeFeatureCollection(featureCollection, writer);

        // 获取生成的GeoJSON字符串
        String geoJsonString = writer.toString();

        // 输出GeoJSON字符串
        System.out.println(geoJsonString);
    }
}