用杰克逊解析JSON Bing的结果

Question

我想用Jackson来解析JSON Bing的结果,但我对如何使用它有点困惑.以下是Bing收到的JSON示例:

{
   "SearchResponse":{
      "Version":"2.2",
      "Query":{
         "SearchTerms":"jackson json"
      },
      "Web":{
         "Total":1010000,
         "Offset":0,
         "Results":[
            {
               "Title":"Jackson JSON Processor - Home",
               "Description":"News: 04-Nov-2011: Jackson 1.9.2 released; 23-Oct-2011: Jackson 1.9.1 released; 04-Oct-2011: Jackson 1.9.0 released (@JsonUnwrapped, value instantiators, value ...",
               "Url":"http:\/\/jackson.codehaus.org\/",
               "CacheUrl":"http:\/\/cc.bingj.com\/cache.aspx?q=jackson+json&d=4616347212909127&w=cbaf5322,11c785e8",
               "DisplayUrl":"jackson.codehaus.org",
               "DateTime":"2011-12-18T23:12:00Z",
               "DeepLinks":"[...]"
            }
         ]
      }
   }
}

我真的只需要结果数组中的数据.这个数组可以有0到n个结果.有人可以提供一个例子来说明如何使用Jackson来反序化"结果"吗？

Answer 1

首先,将您的JSON读作树.ObjectMapper使用该readTree()方法实例化并读取您的JSON .

这会给你一个JsonNode.将结果作为另一个结果JsonNode并循环遍历数组:

final ObjectMapper mapper = new ObjectMapper();

final JsonNode input = mapper.readTree(...);

final JsonNode results = input.get("SearchResponse").get("Web").get("Results");

/*
 * Yes, this works: JsonNode implements Iterable<JsonNode>, and this will
 * cycle through array elements
 */
for (final JsonNode element: results) {
    // do whatever with array elements
}

您还可以考虑使用JSON Schema实现验证输入.无耻的插件:https://github.com/fge/json-schema-validator