public String[] getS3ObjectsNames( String bucketName ) throws Exception {
    Bucket bucket = getBucket( bucketName );
    if ( bucket == null ) {
      throw new Exception( Messages.getString( "S3DefaultService.Exception.UnableToFindBucket.Message", bucketName ) );
    }
    return getS3Objects( bucket ).getObjectSummaries().stream().map( b -> b.getKey() ).toArray( String[]::new );
  }
@Test public void testGetObjectsNamesInEmptyBucket() throws Exception {
    String[] actual = provider.getS3ObjectsNames( BUCKET3_NAME );
    logArray( actual );
    assertEquals( 0, actual.length );
  }