@Test
public void when_initializing_with_null__npe_should_be_thrown() {

	assertThatThrownBy(() -> FetchAtomsObservationAction.of(
		null,
		mock(RadixAddress.class),
		mock(RadixNode.class),
		mock(AtomObservation.class)
	)).isInstanceOf(NullPointerException.class);
	assertThatThrownBy(() -> FetchAtomsObservationAction.of(
		"Hi",
		null,
		mock(RadixNode.class),
		mock(AtomObservation.class)
	)).isInstanceOf(NullPointerException.class);
	assertThatThrownBy(() -> FetchAtomsObservationAction.of(
		"Hi",
		mock(RadixAddress.class),
		null,
		mock(AtomObservation.class)
	)).isInstanceOf(NullPointerException.class);
	assertThatThrownBy(() -> FetchAtomsObservationAction.of(
		"Hi",
		mock(RadixAddress.class),
		mock(RadixNode.class),
		null
	)).isInstanceOf(NullPointerException.class);
}