Question

我有一些使用Jackson属性创建json报告的课程

Map<String, String> myMap = new HashMap<String, String>();
myMap.put("one","test1")
myMap.put("two","test2")
myMap.put("three","test3")
myMap.put("four","test4")
myMap.put("five","test5")

我从HashMap获取报告数据，其中还有其他键值对。

public class SearchResultsViewModel : BindableBase, IRegionMemberLifetime
{
    // Stuff...

    public bool KeepAlive => false;
}

我只需要地图中的第一个到第三个值，其他类中使用其他值。在输出中我想填写Instrument类的值。有干净利落的做法吗？

Answer 1

您可以使用ObjectMapper.convert方法将Instrument类的实例转换为哈希映射，如下所示：

public class JacksonConvert {

    static class Instrument {
        @JsonProperty("one")
        private String myPropOne;
        @JsonProperty("two")
        private String myPropTwo;
        @JsonProperty("three")
        private String myPropThree;

        Instrument(
                final String myPropOne,
                final String myPropTwo,
                final String myPropThree) {
            this.myPropOne = myPropOne;
            this.myPropTwo = myPropTwo;
            this.myPropThree = myPropThree;
        }
    }

    public static void main(String[] args) {
        final ObjectMapper objectMapper = new ObjectMapper();
        final Instrument instrument = new Instrument("a", "b", "c");
        final Map<String, String> report = objectMapper.convertValue(
                instrument,
                new TypeReference<Map<String, String>>() {});
        System.out.println(report);
    }
}

输出：

{one = a，two = b，three = c}

从HashMap获取@JsonProperty值

1 个答案: