用Java打开.shp文件

Question

I am trying to open .shp file downloaded from http://www.naturalearthdata.com/downloads/10m-cultural-vectors/10m-admin-0-countries/ using geotools. My code looks like this:

File file = new File("ne_10m_admin_0_countries.shp");
try{

        Map<String, URL> map = new HashMap<String, URL>(); 
        map.put("url", file.toURI().toURL());

        DataStore dataStore = DataStoreFinder.getDataStore(map);

        System.out.println(DataStoreFinder.getDataStore(map));
        System.out.println(map);

        SimpleFeatureSource featureSource = dataStore.getFeatureSource(dataStore.getTypeNames()[0]);        
        SimpleFeatureCollection collection = featureSource.getFeatures();

        ReferencedEnvelope env = collection.getBounds();
        double left = env.getMinX();
        double right = env.getMaxX();
        double top = env.getMaxY();
        double bottom = env.getMinY();
        System.out.println(left+" "+right);
    }catch(Exception e){
        System.out.println("ahoj" +e.getMessage());
    }

DataStoreFinder.getDataStore() method returns null and that is the problem. Do you have some ideas what am I doing wrong?

I want to open and use this shapefile in order to get coordinates of country borders.

The problem was that i didn't have include other needed jar files. It's working now.

Answer 1

do you have gt-shapefile.jar on the class path?

GeoTools uses an SPI lookup to find datastores based on the parameter map you supply. Another possible check is to call DataStoreFinder.getAllDatastores() to check availability:

Iterator<DataStoreFactorySpi> it = DataStoreFinder.getAllDataStores();
  while (it.hasNext()) {
    DataStoreFactorySpi fac = it.next();
    System.out.println(fac.getDisplayName());
  }

Or if you only ever want to read a Shapefile then create the ShapefileDataStore directly.

Also as a side note I'd recommend using DataUtilities.fileToURL(file) over file.toUri().toUrl() as it handles windows and paths with spaces better.