@Test
  public void testGetAccountByIdResultsDifferent() {
    when(primaryAccountService.getAccountById(anyShort())).thenReturn(testAccount);
    when(secondaryAccountService.getAccountById(anyShort())).thenReturn(null);
    assertEquals("Expected response from primary", testAccount,
        compositeAccountService.getAccountById(testAccount.getId()));
    verify(primaryAccountService).getAccountById(testAccount.getId());
    verify(secondaryAccountService).getAccountById(testAccount.getId());
    assertEquals("Expected one inconsistency", 1, metrics.getAccountInconsistencyCount.getCount());
  }
Test composite getAccountById() with both sources returning different results.
ambry-account/src/test/java/com/github/ambry/account/CompositeAccountServiceTest.java