title: FileDataStore dispose function throw nullPointer Exception
body: <p>im having trouble with the store of FileDataStore. It does the job for me but i found out that it throws java null pointer exception when i dispose it. I debbuged and im sure that the store is not null.</p>
  <p>Here is my code :</p>
  <pre><code>    SimpleFeatureIterator iterator = null;
      FileDataStore store = null;
      try {
          store = FileDataStoreFinder.getDataStore(file);
          SimpleFeatureSource source = store.getFeatureSource();
  
          for (int i = 0; i &lt; store.getFeatureReader().getFeatureType().getAttributeDescriptors().size(); i++) {
              names.add(store.getFeatureReader().getFeatureType().getAttributeDescriptors().get(i).getLocalName());
          }
          SimpleFeatureCollection features = source.getFeatures();
          iterator = features.features();
          while (iterator.hasNext()) {
              // copy the contents of each feature and transform the geometry
              SimpleFeature feature = iterator.next();
              shapeFileData.add(feature.getAttributes());
          }
      } catch (IOException e) {
          System.out.println(e.getLocalizedMessage());
          e.printStackTrace();
      }
      iterator.close();
      store.dispose();
  </code></pre>