Developing a Resource Writer

Overview

A ResourceWriter is an object used to store or delete a Resource. ResourceWriter objects should be registered within the OSGi Service Registry so clients can retrieve an instance when clients need to store a Resource.  See the Working with Resources section in the Developer's guide for more information.

Creating a New ResourceWriter

Creating a ResourceWriter consists of these main steps:

1. Create a Java class that implements the ddf.catalog.resource.ResourceWriter interface.

   ResourceWriter Implementation Skeleton

   import java.io.IOException;
   import java.net.URI;
   import java.util.Map;
   import ddf.catalog.resource.Resource;
   import ddf.catalog.resource.ResourceNotFoundException;
   import ddf.catalog.resource.ResourceNotSupportedException;
   import ddf.catalog.resource.ResourceWriter;
    
   public class SampleResourceWriter implements ResourceWriter {
    
    @Override
    public void deleteResource(URI uri, Map<String, Object> arguments) throws ResourceNotFoundException, IOException {
      // WRITE IMPLEMENTATION
    }
    
    @Override
    public URI storeResource(Resource resource, Map<String, Object> arguments)throws ResourceNotSupportedException, IOException {
      // WRITE IMPLEMENTATION
      return null;
    }
    
    @Override
    public URI storeResource(Resource resource, String id, Map<String, Object> arguments) throws ResourceNotSupportedException, IOException {
    
      // WRITE IMPLEMENTATION
      return null;
    }
   }

2. Register the implementation as a Service in the OSGi Service Registry.

   Blueprint Service Registration Example

   ...
   <service ref="[[ResourceWriterReference]]" interface="ddf.catalog.resource.ResourceWriter" />
   ...

3. Deploy the OSGi bundled packaged service to the DDF run-time.
   • Check the Working with OSGi - Bundles section.