You can use IsNull.nullValue() method:
import static org.hamcrest.Matchers.is;
import static org.hamcrest.Matchers.nullValue;
assertThat(attr.getValue(), is(nullValue()));
You can use IsNull.nullValue() method:
import static org.hamcrest.Matchers.is;
import static org.hamcrest.Matchers.nullValue;
assertThat(attr.getValue(), is(nullValue()));