code: @Override
      public DescribeCacheResult describeCache(DescribeCacheRequest request) {
          request = beforeClientExecution(request);
          return executeDescribeCache(request);
      }
docs: <p>
  Returns information about the cache of a gateway. This operation is only supported in the cached volume, tape and
  file gateway types.
  </p>
  <p>
  The response includes disk IDs that are configured as cache, and it includes the amount of cache allocated and
  used.
  </p>
  
  @param describeCacheRequest
  @return Result of the DescribeCache operation returned by the service.
  @throws InvalidGatewayRequestException
  An exception occurred because an invalid gateway request was issued to the service. For more information,
  see the error and message fields.
  @throws InternalServerErrorException
  An internal server error has occurred during the request. For more information, see the error and message
  fields.
  @sample AWSStorageGateway.DescribeCache
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/storagegateway-2013-06-30/DescribeCache" target="_top">AWS
  API Documentation</a>