Question

我必须完成另一个程序员的项目，他开始使用Jackson注释和REST apis。我没有经验，现在挣扎了好几个小时。我需要像这样解析json数组：

{
...
"id_s": "3011",
"no_s": "Suteki",
"fl": [
         {
             "v": "1",
             "m": "0",
         "id_fs": "243",
           "f_c": "2013-08-09 14:43:54",
          id_tf": "3",
           "u_c": "Aaa",
           _u_c": "1347678779",
             "c": "Carlos Rojas",
           "c_c": "1" 
          }
      ]
}

现有的课程如下：

@EBean
@JsonIgnoreProperties(ignoreUnknown = true)
public class Item implements Serializable, MapMarker {
private static final long serialVersionUID = 1L;

@JsonProperty("id_s")
protected int id;

@JsonProperty("id_sucursal")
public void setId_sucursal(int id_sucursal) {
    this.id = id_sucursal;
}

@JsonProperty("id_fb")
protected String idFacebook;

@JsonProperty("no_s")
private String name;

...
}

我已阅读here如何解析数组，但如何使用Jackson注释获取 jsonResponseString ？我错过了什么？

谢谢！

Answer 1

除了遗漏了许多有助于回答你问题的事情之外，我猜你不确定JSON Arrays如何映射到Java对象。如果是这样，它应该是直截了当的：您将JSON数组映射为Java数组或Collection s（如List s）：

public class Item { // i'll skip getters/setters; can add if you like them
  public String id_s;
  public String no_s;

  public List<Entry> fl;
}

public class Entry {
  public String v; // or maybe it's supposed to be 'int'? Can use that
  public String m;
  public int id_fs; // odd that it's a String in JSON; but can convert
  public String f_c; // could be java.util.Date, but Format non-standard (fixable)
  // and so on.
}

你要么把JSON读作对象：

ObjectMapper mapper = new ObjectMapper();
Item requestedItem = mapper.readValue(inputStream, Item.class); // or from String, URL etc
// or, write to a stream
OutputStream out = ...;
Item result = ...;
mapper.writeValue(out, result);
// or convert to a String
String jsonAsString = mapper.writeValueAsString(result);
// note, however, that converting to String, then outputting is less efficient

我希望这会有所帮助。

Answer 2

我之前从未使用过它，但这似乎帮助了其他用户：How can I serialize this JSON using Jackson annotations?

另外，如果可以，为什么不使用Android默认的JSON类？用随机教程搜索：http://www.androidhive.info/2012/01/android-json-parsing-tutorial/

Jackson注释，REST和json数组解析

2 个答案: