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将Json解析为JavaBean

我试图解析一个由Exiftool生成的Json文件,如下所示:

[{
  "SourceFile": "videos/XaviHernandez.flv",
  "ExifTool": {
    "ExifToolVersion": 8.22
  },
  "System": {
    "FileName": "XaviHernandez.flv",
    "Directory": "videos",
    "FileSize": "16 MB",
    "FileModifyDate": "2010:06:17 09:57:21+02:00",
    "FilePermissions": "rw-r--r--"
  },
  "File": {
    "FileType": "FLV",
    "MIMEType": "video/x-flv"
  }
}]

在具有这种结构的Java bean中:

public class MetadataContentBean {
    ExifToolBean exiftoolBean;
    String SourceFile;
    FileBean fileBean;
    SystemBean systemBean;
//Getters and setter
}

我的java代码如下:

    InputStream is = this.getClass().getClassLoader().getResourceAsStream(filename);
    String jsonTxt = IOUtils.toString(is);
    JSONArray json = (JSONArray) JSONSerializer.toJSON(jsonTxt);
    JSONObject metadatacontent = json.getJSONObject(0);
    ObjectMapper mapper = new ObjectMapper();
    MetadataContentBean meta = new MetadataContentBean();
    mapper.readValue(metadatacontent.toString(), MetadataContentBean.class);
    meta= (MetadataContentBean) JSONObject.toBean(metadatacontent, MetadataContentBean.class);

但我有一个错误:

net.sf.json.JSONException: java.lang.NoSuchMethodException: Unknown property 'ExifTool'
    at net.sf.json.util.PropertySetStrategy$DefaultPropertySetStrategy.setProperty(PropertySetStrategy.java:45)
    at net.sf.json.JSONObject.setProperty(JSONObject.java:1477)
    at net.sf.json.JSONObject.toBean(JSONObject.java:468)
    at net.sf.json.JSONObject.toBean(JSONObject.java:253)
    at com.playence.parser.JSon.Parser(JSon.java:66)
    at com.playence.parser.JSon.main(JSon.java:28)
Caused by: java.lang.NoSuchMethodException: Unknown property 'ExifTool'

我查看了几个论坛,但解决方案是这样的,所以我不知道为什么我没有得到结果

知道吗


共 (2) 个答案

  1. # 1 楼答案

    ObjectMapper mapper = new ObjectMapper();
    MetadataContentBean meta= mapper.readValue(metadatacontent.toString(), MetadataContentBean.class);
    

    所有的信息都在这个元数据中

  2. # 2 楼答案

    这个问题混合了^{}^{}可互换库

    @Blanca为杰克逊做了回答。以下是net.sf.json备选方案:

    JSONArray json = (JSONArray) JSONSerializer.toJSON(jsonTxt);
    JSONObject metadatacontent = json.getJSONObject(0);
    MetadataContentBean meta = (MetadataContentBean) JSONObject.toBean(metadatacontent, MetadataContentBean.class);
    

    抛出NoSuchMethodException: Unknown property 'ExifTool'是因为PropertySetStrategy.DEFAULT需要公共字段或setter,我猜