public List<ContextPropagator> getContextPropagators() {
        return Collections.unmodifiableList(this.contextPropagators);
    }
@Test
    public void testConfigs() {
        assertThat(schedulerService.getCorePoolSize()).isEqualTo(20);
        assertThat(schedulerService.getThreadFactory()).isInstanceOf(NamingThreadFactory.class);
        assertThat(schedulerService.getContextPropagators()).hasSize(1)
            .hasOnlyElementsOfTypes(TestContextPropagators.TestThreadLocalContextPropagatorWithHolder.class);
    }