@Test
public void deleteAProductThatDoesNotExist(){

    final RepositoryHandler repositoryHandler = GrapesTestUtils.getRepoHandlerMock();
    final ProductHandler productHandler = new ProductHandler(repositoryHandler);
    Exception exception = null;
    try {
        productHandler.deleteProduct("doesNotExist");
    }
    catch(Exception e){
        exception = e;
    }
    assertNotNull(exception);
}