java - 将 JSON 字符串反序列化为 POJO 列表

Question

这是我用于反序列化从 Google App Engine 云端点返回的响应的代码:

String jsonString = IOUtils.toString(
    httpResponse.getEntity().getContent(), "UTF-8");

ObjectMapper mapper = new ObjectMapper();
ArrayList<myPOJO> myList= 
    mapper.readValue(jsonString, new TypeReference<ArrayList<MyPOJO>>(){});

jsonString 看起来像这样:

{
  "items" : [ {
    "id" : "12345",
    "name" : "test1"
  }, {
    "id" : "121212",
    "name" : "test2"
  } ]
}

但是我收到了这个错误:

org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of java.util.ArrayList out of START_OBJECT token at [Source: java.io.StringReader@547a7880; line: 1, column: 1]

使用 Jackson 将此 JSON 反序列化为 POJO 列表的正确方法是什么？

Answer 1

尝试直接用映射器反序列化

String jsonString = IOUtils.toString(
        httpResponse.getEntity().getContent(), "UTF-8");

    ObjectMapper mapper = new ObjectMapper();

    List<MyPOJO> myList= mapper.convertValue(jsonString, mapper.getTypeFactory().constructCollectionType(List.class, MyPOJO.class));