GeoTools之shp文件操作

简介

GeoTools 是英国利兹大学(University of Leeds)的James Macgll 从1996 年开始研发的一个操作和显示地图的开源Java 代码库， [1]  提供了一系列符合规范的操作地理空间数据的方法，例如可以用它来实现一个地理信息系统（GIS）。GeoTools库在开发时执行OGC规范。目前GeoTools的最新版本是22-SNAPSHOT。 [2] 

GeoTools是一个开源的Java GIS工具包,可利用它来开发符合标准的地理信息系统。GeoTools提供了OGC(Open Geospatial Consortium)规范的一个实现来作为他们的开发。

操作

本文主要写的是利用GeoTools 连接shp文件，并对其进行增删改。

由于过于简单，就当笔记记录一下，时间宝贵的同学就不要看了。

环境搭建

由于geotools是一个GIS类库，所以直接用maven进行构建就可以。

详细可以参考官方教程：http://docs.geotools.org/

数据源DataStore

这个可以理解为平时Java连接数据的时候那个数据源。

1.gt-main模块geotools支持从一系列数据源访问特征信息(即向量信息)。其他数据存储插件可以从gt-jdbc中获得，用于数据库访问。

数据模块主要是将外部服务、磁盘文件等中的数据(通常以特性的形式)提升到应用程序中。这是您最终可以开始使用工具箱的地方。

而gt-main模块是实现附加DataStore的基础

所以要加入以下依赖

<dependency>
  <groupId>org.geotools</groupId>
  <artifactId>gt-main</artifactId>
  <version>${geotools.version}</version>
</dependency>

2. 获取数据源DataStore

官方文档不建议手工创建数据存储;相反，我们使用FactoryFinder，它将定位支持所请求格式的正确插件，也就是下面代码

public DataStore getDataStore(String shpPath) throws Exception {
        File file = new File(shpPath);
        Map params = new HashMap();
        params.put("url", file.toURI().toURL());

        for (Iterator i = DataStoreFinder.getAvailableDataStores(); i.hasNext(); ) {
            DataStoreFactorySpi factory = (DataStoreFactorySpi) i.next();
            try {
                if (factory.canProcess(params)) {
                    dataStore = factory.createNewDataStore(params);
                    // 设置编码后可以正确读取
                    ((ShapefileDataStore) dataStore).setCharset(Charset.forName("GBK"));
                    typeName = dataStore.getTypeNames()[0];
                    featureSource = dataStore.getFeatureSource(dataStore.getTypeNames()[0]);
                }
            } catch (Throwable warning) {
                warning.printStackTrace();
            }
        }
        return null;
    }

FeatureSource增删改

这个东西可以跟平时的mybatis的那个SqlSession，将增删改进行了封装

它让您能够以Java对象的形式访问地理空间信息。

要查看特性资源，如果当前用户有权修改或锁定特性，则可以支持额外的接口特性恢复和特性锁定。

其中的SimpleFeatureSource就已经封装好了相应增删改的操作API

最终代码如下所列：

1.往shp文件中增加记录

 public void addFeature(List<String> dataList) throws IOException {
        System.out.println("============addFeature=====start=====");
        SimpleFeatureStore store = (SimpleFeatureStore) dataStore.getFeatureSource(typeName);
        SimpleFeatureType featureType = store.getSchema();
        SimpleFeatureBuilder build = new SimpleFeatureBuilder(featureType);
        GeometryBuilder geom = new GeometryBuilder();
        List<SimpleFeature> list = new ArrayList<>();
        for (String row : dataList) {
            String[] rowArr = row.split(",");
            SimpleFeature feature = build.buildFeature(rowArr[0]);
        feature.setAttribute("ID", rowArr[0]);
        feature.setAttribute("NUM", rowArr[1]);
        feature.setAttribute("NAME", rowArr[2]);
        feature.setAttribute("MANAGER", rowArr[3]);
        feature.setAttribute("TYPE", rowArr[4]);
        feature.setAttribute("MESHID", rowArr[5]);
        feature.setAttribute("JDCODE", rowArr[6]);
        list.add(feature);
        }

        SimpleFeatureCollection collection = new ListFeatureCollection(featureType, list);
        Transaction transaction = new DefaultTransaction(handle);
        store.setTransaction(transaction);
        try {
            store.addFeatures(collection);
            transaction.commit(); // actually writes out the features in one go
            System.out.println("============addFeature=====done=====");
        } catch (Exception eek) {
            eek.printStackTrace();
            transaction.rollback();
        }
    }

2.往shp文件中修改一条记录

 public void updateFeature(String id) throws IOException {

        System.out.println("========updateFeature====start====");
        long currentTimeMillis = System.currentTimeMillis();
        Transaction transaction = new DefaultTransaction(handle);
        SimpleFeatureStore store = (SimpleFeatureStore) dataStore.getFeatureSource(typeName);
        store.setTransaction(transaction);
        FilterFactory2 ff = CommonFactoryFinder.getFilterFactory2();
        Filter filter = ff.equals(ff.property("ID"), ff.literal(id));
        SimpleFeatureType featureType = store.getSchema();
        try {
            store.modifyFeatures("ROAD", "xbmchina.cn", filter);
            transaction.commit();
            System.out.println("========updateFeature====end====");
        } catch (Exception eek) {
            eek.printStackTrace();
            transaction.rollback();
        }
        long l = System.currentTimeMillis() - currentTimeMillis;
        System.out.println("耗时："+l/1000.0);

    }

3.往shp文件删除一条数据

 public void removeFeature(Set<String> ids) throws IOException {
        System.out.println("======removeFeature== start ========");
        long currentTimeMillis = System.currentTimeMillis();
        Transaction transaction = new DefaultTransaction(handle);
        SimpleFeatureStore store = (SimpleFeatureStore) dataStore.getFeatureSource(typeName);
        store.setTransaction(transaction);
        FilterFactory2 ff = CommonFactoryFinder.getFilterFactory2();
        List<Filter> match = new ArrayList<>();
        for (String id : ids) {
            Filter aMatch = ff.equals(ff.property("ID"), ff.literal(id));
            match.add(aMatch);
        }
        Filter filter = ff.or(match);
        try {
            store.removeFeatures(filter);
            transaction.commit();
            System.out.println("======removeFeature== done ========");
        } catch (Exception eek) {
            eek.printStackTrace();
            transaction.rollback();
        }
        long l = System.currentTimeMillis() - currentTimeMillis;
        System.out.println("耗时："+l/1000.0);
    }

4.查询shp文件中记录

  public void getFeaturesByDataID(String id) throws IOException, CQLException {
        System.out.println("======getByDataID====start=====");
        long currentTimeMillis = System.currentTimeMillis();
        FilterFactory2 ff = CommonFactoryFinder.getFilterFactory2();
//        Filter filter = CQL.toFilter("ID = 'ef7872a5959448c8bfb24604adc07ada' ");
        Filter filter = ff.equals(ff.property("ID"), ff.literal(id));
        FeatureCollection<SimpleFeatureType, SimpleFeature> features = featureSource.getFeatures(filter);
        System.out.println("features size:" + features.size());
        FeatureIterator<SimpleFeature> featureIterator = features.features();
//        while (featureIterator.hasNext()) {
//            SimpleFeature feature = featureIterator.next();
//            Collection<Property> properties = feature.getProperties();
//            System.out.println(properties);
//        }
        System.out.println("======getByDataID====done=====");
        long l = System.currentTimeMillis() - currentTimeMillis;
        System.out.println("耗时："+l/1000.0);
    }

参考文章

http://docs.geotools.org/latest/userguide/library/data/index.html http://docs.geotools.org/latest/userguide/library/data/datastore.html http://docs.geotools.org/latest/userguide/library/data/featuresource.html

最后

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