@Override
    public Collection<JobManagerRunner> getJobManagerRunners() {
        return new ArrayList<>(this.jobManagerRunners.values());
    }
@Test
    void testGetJobManagerRunners() {
        assertThat(testInstance.getJobManagerRunners()).isEmpty();

        final JobManagerRunner jobManagerRunner0 = TestingJobManagerRunner.newBuilder().build();
        final JobManagerRunner jobManagerRunner1 = TestingJobManagerRunner.newBuilder().build();
        testInstance.register(jobManagerRunner0);
        testInstance.register(jobManagerRunner1);

        assertThat(testInstance.getJobManagerRunners())
                .containsExactlyInAnyOrder(jobManagerRunner0, jobManagerRunner1);
    }