下面的geojson导入postgis,shp导入postgis，postgis导出shp,postgis导出geojson已经封装好
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。

pom文件

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>iwuang</groupId>
    <artifactId>geotools4postgis</artifactId>
    <version>1.0-SNAPSHOT</version>
    <name>geotools4postgis</name>
    <!-- FIXME change it to the project's website -->
    <url>https://github.com/yieryi/geotools4postgis</url>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.7</maven.compiler.source>
        <maven.compiler.target>1.7</maven.compiler.target>
        <geotools.version>21-SNAPSHOT</geotools.version>
        <postgresql.version>42.1.4</postgresql.version>
    </properties>
    <repositories>
        <repository>
            <id>maven2-repository.dev.java.net</id>
            <name>Java.net repository</name>
            <url>http://download.java.net/maven/2</url>
        </repository>
        <repository>
            <id>osgeo</id>
            <name>Open Source Geospatial Foundation Repository</name>
            <url>http://download.osgeo.org/webdav/geotools/</url>
        </repository>
        <repository>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
            <id>boundless</id>
            <name>Boundless Maven Repository</name>
            <url>http://repo.boundlessgeo.com/main</url>
        </repository>
        <repository>
            <id>maven</id>
            <name>Maven Repository Switchboard</name>
            <layout>default</layout>
            <url>http://repo1.maven.org/maven2</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
        <repository>
            <id>osgeo</id>
            <name>Open Source Geospatial Foundation Repository</name>
            <url>http://download.osgeo.org/webdav/geotools/</url>
        </repository>
    </repositories>
    <dependencies>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-shapefile</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-swing</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-main</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools.jdbc</groupId>
            <artifactId>gt-jdbc-postgis</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-metadata</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-referencing</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-geojson</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-epsg-hsql</artifactId>
            <version>${geotools.version}</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.alibaba/fastjson -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.47</version>
        </dependency>
        <!--非必需，简化I/O操作-->
        <dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>2.6</version>
        </dependency>
        <dependency>
            <groupId>org.postgis</groupId>
            <artifactId>postgis-driver</artifactId>
            <version>1.0</version>
        </dependency>
    </dependencies>
</project>
PostgisDataStore类




    
 
@Data
public class PostgisDataStore {
    private static DataStore postgisDataStore = null;
    private static String dbtype = null;
    private static String host = null;
    private static String port = null;
    private static String database = null;
    private static String schema = null;
    private static String username = null;
    private static String password = null;
    public PostgisDataStore() {
    public static DataStore getInstance() {
        if (postgisDataStore == null) {
            Map<String, Object> params = new HashMap<String, Object>();
            params.put(PostgisNGDataStoreFactory.DBTYPE.key, dbtype);
            params.put(PostgisNGDataStoreFactory.HOST.key, host);
            params.put(PostgisNGDataStoreFactory.PORT.key, new Integer(port));
            params.put(PostgisNGDataStoreFactory.DATABASE.key, database);
            params.put(PostgisNGDataStoreFactory.SCHEMA.key, schema);
            params.put(PostgisNGDataStoreFactory.USER.key, username);
            params.put(PostgisNGDataStoreFactory.PASSWD.key, password);
            try {
                postgisDataStore = DataStoreFinder.getDataStore(params);
                logger.info("\nPostgisDataStore 初始化geotools中的 Datastore成功\n");
            } catch (IOException e) {
                logger.error("\nPostgisDataStore 初始化geotools中的 Datastore失败\n");
                logger.error(e.getMessage());
        return postgisDataStore;
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<SimpleFeatureType, SimpleFeature> featureWriter = pgDatastore.getFeatureWriterAppend(tablename, Transaction.AUTO_COMMIT);        while (iterator.hasNext()) {
            Feature feature = iterator.next();
            SimpleFeature simpleFeature = featureWriter.next();
            Collection<Property> properties = feature.getProperties();
            Iterator<Property> 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<SimpleFeatureType, SimpleFeature> featureWriter = pgDatastore.getFeatureWriterAppend(tablename, Transaction.AUTO_COMMIT);        while (iterator.hasNext()) {
            Feature feature = iterator.next();
            SimpleFeature simpleFeature = featureWriter.next();
            Collection<Property> properties = feature.getProperties();
            Iterator<Property> 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<SimpleFeature> iterator = featureCollection.features();
        SimpleFeatureType pgfeaturetype = pgDatastore.getSchema(tablename);
        File file = new File(shpPath);
        if (!validateShp(shpPath, false)) return false;
        Map<String, Serializable> params = new HashMap<String, Serializable>();
        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<SimpleFeatureType, SimpleFeature> featureWriter = shpDataStore.getFeatureWriter(shpDataStore.getTypeNames()[0], AUTO_COMMIT);
        while (iterator.hasNext()) {
            Feature feature = iterator.next();
            SimpleFeature simpleFeature = featureWriter.next();
            Collection<Property> properties = feature.getProperties();
            Iterator<Property> 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;
                    下面的geojson导入postgis,shp导入postgis，postgis导出shp,postgis导出geojson已经封装好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。pom
上期我介绍了geotools读取shp文件的事例 （geotools系列1-读取shp文件），本次说明读取读取postgis里表数据的代码，依旧是读取数据打印出来展示。
1、环境，maven依赖等，参见上次 geotools系列1-读取shp文件 。
2、直接上java代码
package com.jjxliu.geotools.geotools_t1;
import ...
				
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本文主要介绍了geojsonio包导入、使用rgdal包、使用sf包导入、geojson、topojson等相关内容。本文来自微信公众号-数据小魔方，由火龙果软件Anna编辑、推荐。以前在处理gis数据的时候，都是直接导入本地shp素材、本地geojson素材，本地topojson素材，自从接触postgis数据之后，深感使用规范的存储系统来统一管理gis数据的好处，特别是数据量大了之后，优势便更加明显，你可以选择将很多需要做空间计算的步骤转移到Postgis数据库内进行计算，要知道Postgis提供的空间计算能力与R和Python这种应用导向的工具相比，优势要大得多。在批量导入素材之前，我们
				
Geotools操作GeoJSON：解析FeatureCollection对象文件一、解析FeatureCollection对象文件1.1 geotools操作GeoJSON过程中的问题及相关源码(转载自：Shanks7529)1.2 方法二：读取本地txt文件进行解析
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    "type":"Fea...
				
GeoTools是一个开源的Java工具包，可用于处理地理空间数据。GeoTools提供了对GeoJSON格式的支持，可以使用GeoTools解析GeoJSON数据。
以下是一个简单的示例代码，展示了如何使用GeoTools解析GeoJSON数据：
```java
File geojsonFile = new File("path/to/geojson/file"); // GeoJSON文件路径
// 创建GeoJSON文件读取器
GeoJSONDataStoreFactory dataStoreFactory = new GeoJSONDataStoreFactory();
Map<String, Object> params = new HashMap<>();
params.put(GeoJSONDataStoreFactory.URLP.key, geojsonFile.toURI().toURL());
GeoJSONDataStore dataStore = (GeoJSONDataStore) dataStoreFactory.createDataStore(params);
// 获取GeoJSON数据源中的FeatureCollection
SimpleFeatureSource featureSource = dataStore.getFeatureSource(dataStore.getTypeNames()[0]);
SimpleFeatureCollection featureCollection = featureSource.getFeatures();
// 遍历FeatureCollection
try (SimpleFeatureIterator featureIterator = featureCollection.features()) {
    while (featureIterator.hasNext()) {
        SimpleFeature feature = featureIterator.next();
        Geometry geometry = (Geometry) feature.getDefaultGeometry(); // 获取几何对象
        // 对几何对象进行操作
        // ...
上述代码首先创建了一个GeoJSON文件读取器，然后使用该读取器获取GeoJSON数据源中的FeatureCollection。接着遍历FeatureCollection，对其中的每个Feature进行操作。
需要注意的是，使用GeoTools解析GeoJSON数据时，需要先将GeoJSON文件转换为GeoJSON数据源，然后再从数据源中获取FeatureCollection。GeoTools支持的数据源类型包括文件、URL、InputStream等。