list<map<String, String> >转list<map<String, Object>>

 List<Map<String, Object>> datas = null;
 List<Map<String, Double>> data = new ArrayList<Map<String, Double>>(employeeMonthlySalaries.size());
 datas = Lists.transform(data, new Function<Map<String, Double>, Map<String, Object>>() {
                @Override
                public Map<String, Object> apply(Map<String, Double> input) {
                    Map<String, Object> output = new HashMap<>(input.size());
                    output.putAll(input);
                    return output;
                }
            });