### Question:
DoctorStatisticsServiceImpl implements DoctorStatisticsService { private List<HashMap> addInvoicesAndVisits(List<HashMap> result, List<HashMap> invoices, List<HashMap> visits){ for(HashMap r: result){ String userName = r.get("userName").toString(); for(HashMap v: visits){ if(userName.equals(v.get("name").toString())){ r.put("visits", v.get("visits")); break; } } for(HashMap i: invoices){ if(userName.equals(i.get("name").toString())){ r.put("invoiceAmount", i.get("invoice_amount")); break; } } } return result; }  @Override CommonResult doctorStatistics(String beginDateStr, String endDateStr); @Override CommonResult doctorStatisticsByUserIdAndDate(String dateStr, Integer userId);  }### Answer:
@Test public void testAddInvoicesAndVisits() throws Exception { }