code: public ModelNode readResource(Address addr, boolean recursive) throws Exception {
          final ModelNode request = createRequest(READ_RESOURCE, addr);
          request.get("recursive").set(recursive);
          final ModelNode results = getModelControllerClient().execute(request, OperationMessageHandler.logging);
          if (isSuccess(results)) {
              final ModelNode resource = getResults(results);
              return resource;
          } else {
              return null;
          }
      }
docs: This returns information on the resource at the given address, recursively
  returning child nodes with the result if recursive argument is set to <code>true</code>.
  This will not return an exception if the address points to a non-existent resource, rather,
  it will just return null. You can use this as a test for resource existence.
  
  @param addr the address of the resource
  @param recursive if true, return all child data within the resource node
  @return the found item or null if not found
  @throws Exception if some error prevented the lookup from even happening