}
@Test
public void testGarbageCollectUnusedElbVmsWhenVariableUnusedElbVmsIsNull() throws Exception {
ElasticLbVmMapDao elasticLbVmMapDaoMock = mock(ElasticLbVmMapDao.class);
when(elasticLbVmMapDaoMock.listUnusedElbVms()).thenReturn(null);
Whitebox.setInternalState(elasticLoadBalancerManagerImpl, "_elbVmMapDao", elasticLbVmMapDaoMock);
try {
elasticLoadBalancerManagerImpl.garbageCollectUnusedElbVms();
} catch (NullPointerException e) {