我正在尝试制作一个2D平铺游戏，我试图通过从JSON文件导入它们来添加项目。我尝试使用GSON库导入JSON文件，但是每当我运行代码时，我都会收到以下错误：

java.lang.IllegalArgumentException: class javax.swing.JFrame declares multiple JSON fields named state
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getBoundFields(ReflectiveTypeAdapterFactory.java:172)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.create(ReflectiveTypeAdapterFactory.java:102)
    at com.google.gson.Gson.getAdapter(Gson.java:457)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.createBoundField(ReflectiveTypeAdapterFactory.java:117)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getBoundFields(ReflectiveTypeAdapterFactory.java:166)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.create(ReflectiveTypeAdapterFactory.java:102)
    at com.google.gson.Gson.getAdapter(Gson.java:457)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.createBoundField(ReflectiveTypeAdapterFactory.java:117)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getBoundFields(ReflectiveTypeAdapterFactory.java:166)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.create(ReflectiveTypeAdapterFactory.java:102)
    at com.google.gson.Gson.getAdapter(Gson.java:457)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.createBoundField(ReflectiveTypeAdapterFactory.java:117)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getBoundFields(ReflectiveTypeAdapterFactory.java:166)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.create(ReflectiveTypeAdapterFactory.java:102)
    at com.google.gson.Gson.getAdapter(Gson.java:457)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.createBoundField(ReflectiveTypeAdapterFactory.java:117)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.getBoundFields(ReflectiveTypeAdapterFactory.java:166)
    at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.create(ReflectiveTypeAdapterFactory.java:102)
    at com.google.gson.Gson.getAdapter(Gson.java:457)
    at com.google.gson.internal.bind.ArrayTypeAdapter$1.create(ArrayTypeAdapter.java:48)
    at com.google.gson.Gson.getAdapter(Gson.java:457)
    at com.google.gson.Gson.fromJson(Gson.java:921)
    at com.google.gson.Gson.fromJson(Gson.java:860)
    at dev.bako.tilegame.utils.JSONImporter.ItemJSONReader(JSONImporter.java:13)
    at dev.bako.tilegame.Game.init(Game.java:63)
    at dev.bako.tilegame.Game.run(Game.java:101)
    at java.lang.Thread.run(Thread.java:745)

.

JSONImter类如下：

public class JSONImporter {

    public static void ItemJSONReader() throws Exception {

        Item[] items = new Gson().fromJson(new FileReader("res/JSON/Item.json"), Item[].class);//This is where I get the error
        System.out.println("Loaded file!" + items); 

    }

}

我尝试导入的JSON文件：

{
  "Wood": {
    "id": 0
  },
  "Rock": {
    "id": 2
  }
}