GeoTools CollectionFeatureSource Disk Cleanup

Question

I am using GeoTools to load a GeoJSON file into a PostGIS table.

My code looks like this:

        FeatureJSON featureJSON = new FeatureJSON();
        File geojsonFile = getFile(dataResource); // Loads the GeoJSON as a File
        SimpleFeatureCollection featureCollection = (SimpleFeatureCollection) featureJSON.readFeatureCollection(geojsonFile);
        SimpleFeatureType featureSchema = featureJSON.readFeatureCollectionSchema(geojsonFile, true);
        FeatureSource<SimpleFeatureType, SimpleFeature> geojsonFeatureSource = new CollectionFeatureSource(featureCollection);

Once I get the geojsonFeatureSource I can then use this to load the data into PostGIS using a DataStore object for PostGIS.

My problem occurs when I try to delete the GeoJSON file afterwards (held by the geojsonFile variable in my example). This file has a lock on it and cannot be deleted.

Now, when using previous Data Stores (such as Shapefiles) I am always able to call .dispose() on the FeatureSource. However, in this GeoJSON case, I am not able to call .dispose() on the CollectionFeatureSource because it is an "In Memory Data Store" - whatever that means.

My cleanup logic looks like:

            featureJSON = null;
            geojsonFeatureSource = null;
            featureCollection = null;
            featureSchema = null;
            geojsonFile.delete();

How can I get these objects to release their lock on the GeoJSON file so that I can clean up this input GeoJSON file?

Answer 1

I was unable to remove the lock when loading via a File object.

However, I am able to achieve the same level of functionality passing an InputStream into GeoTools, rather than passing in the File directly.

        FeatureJSON featureJSON = new FeatureJSON();
        InputStream geoJsonInputStream = getGeoJsonInputStream(dataResource);
        SimpleFeatureCollection featureCollection = (SimpleFeatureCollection) featureJSON.readFeatureCollection(geoJsonInputStream);
        FeatureSource<SimpleFeatureType, SimpleFeature> geojsonFeatureSource = new CollectionFeatureSource(featureCollection);

By never giving access to the File to GeoTools, a lock is never held. Once my logic is done, I can close the InputStream that I have passed to GeoTools, and then safely delete the original file.