杰克逊解析特定数组

Question

我正在使用杰克逊解析api结果，这似乎运作良好。

的Java：

public static void jsonIn(String st){ 
     try { 
     JsonFactory jfactory = new JsonFactory(); 
     /*** read from URL ***/ 
     JsonParser jParser = jfactory.createJsonParser(new URL(st)); 
     // loop until token equal to "}" 
     while (jParser.nextToken() != JsonToken.END_ARRAY) { 
      String fieldname = jParser.getCurrentName(); 
      if ("id".equals(fieldname)) { 
       // current token is "id", 
         // move to next, which is "id"'s value 
      try{ 
       jParser.nextToken(); 
       } 
      catch (Exception e){ 

      } 
       System.out.println(jParser.getText()); // display id 
      } 
      } 
      jParser.close(); 
     } catch (JsonGenerationException e) { 
      e.printStackTrace(); 
     } 

     } 

问：

However-我想要的结果（现场： “ID”）都在阵 “项目”。上面的代码从第一个数组“查询”开始，只发送给我一个名为“id”的元素，我不关心它。然后它停止基于while语句的解析并且不会到达“items”数组。我如何更改我的代码以跳到我感兴趣的数组“项目”，以便我可以获得我想要的“id”字段？

JSON：

{ 
"app": "Sale", 
"avail": { 
    "type": "application/json", 
}, 
"queries": { 
    "unAvailURIs": [ 
    { 
    "id": "1sdf6gf3jf80dhb3", 
    "results": "57", 
    "searchTerms": "lycos.com", 
    "startIndex": 11 
    } 
    ], 
    "apiSource": [ 
    { 
    "title": "go****y", 
    "totalResults": "579000", 
    "auctionPhrase": "lycos.com", 
    "count": 10, 
    "startIndex": 1, 
    "id": "in", 
    } 
    ] 
}, 
"pullAPI": { 
    "search": "lycos.com" 
}, 
"searchInformation": { 
    "searchTime": 0.025345, 
    "totalResults": "57600100", 
}, 
"items": [ 
    { 
    "id": "GD172993", 
    "title": "lycos.com", 
    .... 

Answer 1

我似乎已经错过了一个SO后我一直在寻找：Parsing JSON Bing results with Jackson。 谢谢@fge的解释ObjectMapper和readTree()。
我简单地替换了我的顶部try声明的开头，如下所示：

try {  
    JsonFactory jfactory = new JsonFactory(); 
    JsonParser jParser = jfactory.createJsonParser(new URL(st)); 
    ObjectMapper mapper = new ObjectMapper(); 
    JsonNode input = mapper.readTree(jParser); 
    final JsonNode results = input.get("items"); 
    // loop until token equal to "}" 
    for (final JsonNode element: results) { 
     JsonNode fieldname = element.get("id"); 
     System.out.println(fieldname.toString());