@Test
@SuppressWarnings("null")
public void testDataSource() {

    DataSource input = DataSource.of("myprovider", "1234");
    assertThat(checkProvider("myprovider", input))
            .isSameAs(input);
    assertThatThrownBy(() -> checkProvider("xxx", input))
            .isInstanceOf(IllegalArgumentException.class);
    assertThatThrownBy(() -> checkProvider(null, input))
            .isInstanceOf(NullPointerException.class);
    assertThatThrownBy(() -> checkProvider("myprovider", (DataSource) null))
            .isInstanceOf(NullPointerException.class);
}