Java遍历map

 List<Mtsubstation> mtsubstations = mtsubstationDao.selectListWithTransformer();
 Map<String, List<Mtsubstation>> mapTemp = mtsubstations.stream().collect(groupingBy(Mtsubstation::getVoltageLevelName));
 for (Map.Entry<String, List<Mtsubstation>> entry : mapTemp.entrySet()) {
  　　// System.out.println("key= " + entry.getKey() + " and value= " + entry.getValue());
 }

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