錯誤：com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException：無法識別的字段

Question

我正在嘗試閱讀以下 json 和 map 到 model object。

Model class：

 public class User {
    private String name;
    private int age;
    private List<String> messages;
}

下面是用於map json model的示例代碼（MyModelData.java）

ObjectMapper mapper = new ObjectMapper();
    try {
        String jsonInString = "{\"age\":33,\"messages\":[\"msg 1\",\"msg 2\"],\"name\":\"mkyong\"}";
        User user1 = mapper.readValue(jsonInString, User.class);
        System.out.println(user1);
    } catch (Exception e) {
        System.out.println("ex " + e);
    }

以下是例外情況：

   com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "age" (class com.dsr.User), not marked as ignorable (0 known properties: ])
 at [Source: (String)"{"age":33,"messages":["msg 1","msg 2"],"name":"mkyong"}"; line: 1, column: 10] (through reference chain: com.dsr.User["age"])

將 json 字符串映射到 model object 時顯示上述異常。 用戶 class 定義了年齡屬性。

Answer 1

我不知道這是否是您的代碼的唯一問題，但對於ID:4 in the JSON after Claim related to issueID您缺少結束語標記。