基于GeoTools做GeoJson，PostGIS，Shapefile的转换

github:https://github.com/yieryi/geotools4postgis/
下面的geojson导入postgis,shp导入postgis，postgis导出shp,postgis导出geojson已经封装好在GitHub上。maven里导入对应的jar（复制pom相应代码），复制PostgisUtility.java和PostgisDataStore.java文件,就可以按照app.java里的方式调用这两个类文件里封装完的四个方法。这四个方法代码如下： 
validateshp,validategeojson方法为验证路径有效性，可不调用或者自己判断，否则java可能会报文件路径异常 
转载请说明来源。shp文件导入到postgis数据库中

   public static boolean importShp(String shppath, String tablename) throws IOException {
        if (!validateShp(shppath, true)) return false;
        DataStore pgDatastore = postgisDataStore.getInstance();
        ShapefileDataStore shapefileDataStore = null;
        shapefileDataStore = new ShapefileDataStore(new File(shppath).toURI().toURL());
        shapefileDataStore.setCharset(Charset.forName("utf-8"));
        FeatureSource featureSource = shapefileDataStore.getFeatureSource();
        FeatureCollection featureCollection = featureSource.getFeatures();
        SimpleFeatureType shpfeaturetype = shapefileDataStore.getSchema();
        SimpleFeatureTypeBuilder typeBuilder = new SimpleFeatureTypeBuilder();
        typeBuilder.init(shpfeaturetype);
        typeBuilder.setName(tablename);
        SimpleFeatureType newtype = typeBuilder.buildFeatureType();
        pgDatastore.createSchema(newtype);
        logger.info("\npostgis创建数据表成功");

        FeatureIterator iterator = featureCollection.features();
        FeatureWriter featureWriter = pgDatastore.getFeatureWriterAppend(tablename, Transaction.AUTO_COMMIT);        while (iterator.hasNext()) {
            Feature feature = iterator.next();
            SimpleFeature simpleFeature = featureWriter.next();
            Collection properties = feature.getProperties();
            Iterator propertyIterator = properties.iterator();
            while (propertyIterator.hasNext()) {
                Property property = propertyIterator.next();
                simpleFeature.setAttribute(property.getName().toString(), property.getValue());
            }
            featureWriter.write();
        }
        iterator.close();
        featureWriter.close();
        shapefileDataStore.dispose();
        pgDatastore.dispose();
        logger.info("\nshp导入postgis成功");
        return true;
    }

把geojson格式数据导入到postgsi，存储坐标和所有属性

public static boolean importGeojson(String geojsonpath, String tablename) throws IOException {
        if (!validateGeojson(geojsonpath, true)) return false;
        DataStore pgDatastore = postgisDataStore.getInstance();
        FeatureJSON featureJSON = new FeatureJSON();
        FeatureCollection featureCollection = featureJSON.readFeatureCollection(new FileInputStream(geojsonpath));
        SimpleFeatureType geojsontype = (SimpleFeatureType) featureCollection.getSchema();
        SimpleFeatureTypeBuilder typeBuilder = new SimpleFeatureTypeBuilder();
        typeBuilder.init(geojsontype);
        typeBuilder.setName(tablename);
        SimpleFeatureType newtype = typeBuilder.buildFeatureType();
        pgDatastore.createSchema(newtype);

        FeatureIterator iterator = featureCollection.features();
        FeatureWriter featureWriter = pgDatastore.getFeatureWriterAppend(tablename, Transaction.AUTO_COMMIT);        while (iterator.hasNext()) {
            Feature feature = iterator.next();
            SimpleFeature simpleFeature = featureWriter.next();
            Collection properties = feature.getProperties();
            Iterator propertyIterator = properties.iterator();
            while (propertyIterator.hasNext()) {
                Property property = propertyIterator.next();
                simpleFeature.setAttribute(property.getName().toString(), property.getValue());
            }
            featureWriter.write();
        }
        iterator.close();
        featureWriter.close();
        pgDatastore.dispose();
        return true;
    }

导出postgis数据库中的指定矢量表为shp文件

public static boolean exportShp(String tablename, String shpPath) throws IOException, FactoryException {
        DataStore pgDatastore = postgisDataStore.getInstance();
        FeatureSource featureSource = pgDatastore.getFeatureSource(tablename);
        FeatureCollection featureCollection = featureSource.getFeatures();
        FeatureIterator iterator = featureCollection.features();
        SimpleFeatureType pgfeaturetype = pgDatastore.getSchema(tablename);
        File file = new File(shpPath);

        if (!validateShp(shpPath, false)) return false;

        Map params = new HashMap();
        params.put(ShapefileDataStoreFactory.URLP.key, file.toURI().toURL());
        ShapefileDataStore shpDataStore = (ShapefileDataStore) new ShapefileDataStoreFactory().createNewDataStore(params);
        String srid = pgfeaturetype.getGeometryDescriptor().getUserData().get("nativeSRID").toString();
        SimpleFeatureTypeBuilder typeBuilder = new SimpleFeatureTypeBuilder();
        typeBuilder.init(pgfeaturetype);
        if (!srid.equals("0")) {
            CoordinateReferenceSystem crs = CRS.decode("EPSG:" + srid, true);
            typeBuilder.setCRS(crs);
        }
        pgfeaturetype = typeBuilder.buildFeatureType();
        shpDataStore.setCharset(Charset.forName("utf-8"));
        shpDataStore.createSchema(pgfeaturetype);

        FeatureWriter featureWriter = shpDataStore.getFeatureWriter(shpDataStore.getTypeNames()[0], AUTO_COMMIT);

        while (iterator.hasNext()) {
            Feature feature = iterator.next();
            SimpleFeature simpleFeature = featureWriter.next();
            Collection properties = feature.getProperties();
            Iterator propertyIterator = properties.iterator();

            while (propertyIterator.hasNext()) {
                Property property = propertyIterator.next();
                if (geomfield(property.getName().toString())) {
                    simpleFeature.setAttribute("the_geom", property.getValue());
                    continue;
                }
                simpleFeature.setAttribute(property.getName().toString(), property.getValue());
            }
            featureWriter.write();
        }
        iterator.close();
        featureWriter.close();
        pgDatastore.dispose();
        return true;
    }

导出postgis数据库中的指定矢量表为geojson文件

public static boolean exportGeojson(String tablename, String geojsonPath) throws IOException, FactoryException {
        DataStore pgDatastore = postgisDataStore.getInstance();
        FeatureSource featureSource = pgDatastore.getFeatureSource(tablename);
        FeatureCollection featureCollection = featureSource.getFeatures();
        FeatureJSON featureJSON = new FeatureJSON();
        File file = new File(geojsonPath);
        if (!file.exists()) {
            file.createNewFile();
        }
        OutputStream outputStream = new FileOutputStream(file, false);
        featureJSON.writeFeatureCollection(featureCollection, outputStream);
        pgDatastore.dispose();
        return true;
    }