java - 如何使用 gson 迭代 json 数据

Question

我的 json 字符串是:

{
   "recordsTotal":1331,
   "data":[
      {
         "part_number":"3DFN64G08VS8695 MS",
         "part_type":"NAND Flash",
         "id":1154,
         "manufacturers":[
            "3D-Plus"
         ]
      },
      {
         "part_number":"3DPM0168-2",
         "part_type":"System in a Package (SiP)",
         "id":452,
         "manufacturers":[
            "3D-Plus"
         ]
      },
      {
         "part_number":"3DSD1G16VS2620 SS",
         "part_type":"SDRAM",
         "id":269,
         "manufacturers":[
            "3D-Plus"
         ]
      }
   ]
}

这段代码让我可以访问两个最高级别的元素:

JsonObject jsonObject = new JsonParser().parse(jsonString).getAsJsonObject(); 
System.out.println("data : " + jsonObject.get("data")); 
System.out.println("recordsTotal : " + jsonObject.get("recordsTotal"));

但是我想要做的是迭代“data”内的所有对象并创建一个part_numbers列表。我该怎么做？

Answer 1

JsonArray is an Iterable<JsonElement> 。所以你可以使用for in循环。

JsonObject jsonObject = new JsonParser().parse(jsonString).getAsJsonObject();
final JsonArray data = jsonObject.getAsJsonArray("data");
System.out.println("data : " + data);
System.out.println("recordsTotal : " + jsonObject.get("recordsTotal"));
List<String> list = new ArrayList<String>();
for (JsonElement element : data) {
    list.add(((JsonObject) element).get("part_number").getAsString());

}