JsonMapper 转数组

假设你有一个 JSON 字符串如下：

{
  "colors": [
    {
      "color": "red",
      "code": "#FF0000"
    },
    {
      "color": "green",
      "code": "#00FF00"
    },
    {
      "color": "blue",
      "code": "#0000FF"
    }
  ]
}

你可以使用 JsonMapper 库将其转换为一个数组：

import com.fasterxml.jackson.databind.ObjectMapper;

ObjectMapper mapper = new ObjectMapper();
String json = "{\"colors\":[{\"color\":\"red\",\"code\":\"#FF0000\"},{\"color\":\"green\",\"code\":\"#00FF00\"},{\"color\":\"blue\",\"code\":\"#0000FF\"}]}";

try {
    Map<String, Object> map = mapper.readValue(json, new TypeReference<Map<String, Object>>(){});
    List<Map<String, Object>> colors = (List<Map<String, Object>>) map.get("colors");
    for (Map<String, Object> color : colors) {
        System.out.println(color.get("color") + " - " + color.get("code"));
    }
} catch (IOException e) {
    e.printStackTrace();
}

输出：

red - #FF0000
green - #00FF00
blue - #0000FF