java - 如何使用 gson 反序列化未知命名数组 json

Question

json 看起来像这样:

"hour_totals": {
      "382423": {
        "imp": 126,
        "clk": 1,
        "spend": "$0.03",
        "conv": 0,
        "cpm": "$0.22",
        "cpc": "$0.03",
        "ctr": "0.79%",
        "cpa": "$Inf"
      },
      "382424": {
        "imp": 209,
        "clk": 1,
        "spend": "$0.05",
        "conv": 0,
        "cpm": "$0.23",
        "cpc": "$0.05",
        "ctr": "0.48%",
        "cpa": "$Inf"
      }}

我阅读了 20 多个答案，但无法找到如何反序列化这样的结构，请帮助了解该类的外观，因为时间不是固定字符串。

Answer 1

要使用 Gson 解析此 JSON，您需要两个步骤。

1. 定义此类:

   public class Total {
   
      Map<String, HourData> hour_totals;
   
      @Override
      public String toString() {
         return "Total [hour_totals=" + hour_totals + "]";
      }
   
   }
   

   其中 HourData 是

   public class HourData {
   
      Integer imp;
      Integer clk;
      String spend;
      Integer conv;
      String cpm;
      String cpc;
      String cpa;
   
      @Override
      public String toString() {
         return "HourData [imp=" + imp + ", clk=" + clk + ", spend=" + spend
               + ", conv=" + conv + ", cpm=" + cpm + ", cpc=" + cpc + ", cpa="
               + cpa + "]";
      }
   
    }
   

2. 修改您的“Json 字符串”，因为它不是有效的 Json(请参阅下面的更多详细信息)。您只需要像下面的代码一样添加大括号:

   public class Q19201300 {
   
     public static void main(String[] args) {
         String json = "\"hour_totals\": {  "
                 + "  \"382423\": {                 "
                 + "  \"imp\": 126,                 "
                 + "  \"clk\": 1,                   "
                 + "  \"spend\": \"$0.03\",         "
                 + "  \"conv\": 0,                  "
                 + "  \"cpm\": \"$0.22\",           "
                 + "  \"cpc\": \"$0.03\",           "
                 + "  \"ctr\": \"0.79%\",           "
                 + "  \"cpa\": \"$Inf\"             "
                 + "},                              "
                 + "\"382424\": {                   "
                 + "  \"imp\": 209,                 "
                 + "  \"clk\": 1,                   "
                 + "  \"spend\": \"$0.05\",         "
                 + "  \"conv\": 0,                  "
                 + "  \"cpm\": \"$0.23\",           "
                 + "  \"cpc\": \"$0.05\",           "
                 + "  \"ctr\": \"0.48%\",           "
                 + "  \"cpa\": \"$Inf\"             "
                 + "}}                              ";
   
         Total t = new Gson().fromJson("{" + json + "}", Total.class);
   
         System.out.println(t);
   
     }
   }
   

这会给你:

Total [hour_totals={382423=HourData [imp=126, clk=1, spend=$0.03, conv=0, cpm=$0.22, cpc=$0.03, cpa=$Inf], 382424=HourData [imp=209, clk=1, spend=$0.05, conv=0, cpm=$0.23, cpc=$0.05, cpa=$Inf]}]

关于你的字符串。来自 JSON 官方语法( http://www.ietf.org/rfc/rfc4627.txt ):

1. JSON Grammar

   A JSON text is a sequence of tokens. The set of tokens includes six structural characters, strings, numbers, and three literal names.

   A JSON text is a serialized object or array.