如何迭代列表<Map<String,Object> &gt; 在 Java 中

Question

I have one List which contain one map i want to iterate is

List<Map<String, Object>> featureService=featureSubscriptionDao.getUnsubscribedSevice();

my dao method is

@Override
public List<Map<String, Object>> getUnsubscribedSevice() {
    String sql="select * from tblservice where public='false'";
    return getJdbcTemplate().queryForList(sql);
}

any help ?

Answer 1

List<Map<String, Object>> featureServices = getUnsubscribedSevice();

for (Map<String, Object> featureService : featureServices) {
    for (Map.Entry<String, Object> entry : featureService.entrySet()) {
       System.out.println(entry.getKey() + ": " + entry.getValue());
    }
}

Answer 2

In Java 8 you can simply use a lambda function.

    featureService.forEach(service -> 
                service.forEach((k, v) -> System.out.println(k + ": " + v)
   ));

Answer 3

Extract from the lists of the map:-

for (Map<String, Object> objectMap : cal.getMap_formula()) {
                        objectMap.keySet();//method 1st
                        objectMap.containsKey("key_name");//method 2nd
                        objectMap.get("key_name");//method 3rd
                    }