如何获取某些 Json 变量 [closed]

问：

我正在编写我的第一个 java 项目，货币转换器，但我无法从 json 文件中获取某些变量以将其添加到我的函数中

public class Main {

    public static void converter() {


    b1.addActionListener(new ActionListener(){
        public void actionPerformed(ActionEvent e) {

            double d = Double.parseDouble(t1.getText());
            double d1 = (d/Json_Reader.rateUSD);
            String str1 = String.valueOf(df.format(d1));
            t2.setText(str1);
        }
    });
    
    b2.addActionListener(new ActionListener () {
        public void actionPerformed(ActionEvent e) {

            double d2 = Double.parseDouble(t2.getText());
            double d3 = (d2 * Json_Reader.rateUSD); 
            String str2 = String.valueOf(df.format(d3));
            t1.setText(str2);
        }
    });

    public static void main(String[] args) throws IOException, URISyntaxException {
        converter();
        Json_Reader.UrlToRates();
    }

}

我删除了 Main 中的大部分 AWT 代码

public class Json_Reader {
    static double rateUSD;

    public static void UrlToRates() throws IOException, URISyntaxException, JSONException {

    String sURL = "https://bank.gov.ua/NBUStatService/v1/statdirectory/exchange?json";  //just a string
    URL url = new URI(sURL).toURL();  //converting URI to URL
    URLConnection request = url.openConnection();
    request.connect();  //openning connection

    Gson gson = new Gson();  //creating Gson object
    BufferedReader br = new BufferedReader(new InputStreamReader((InputStream) request.getContent()));  //geting input as StringBuilder
    StringBuilder sb = new StringBuilder();
    String line;
    JsonElement jelem = gson.fromJson(br, JsonElement.class);  //converting StringBuilder to JsonElement 

    while ((line = br.readLine()) != null) {  //converting StringBuilder to String
      sb.append(line);}
    
    JsonObject jo = jelem.getAsJsonObject();  //creating JsonObject
    String req_result = jo.get("result").getAsString();  //geting result as a String
    System.out.println(req_result);
    rateUSD = JsonPath.using(Configuration.defaultConfiguration()).parse(jo).read("$..rate[1]", Double.class);  //geting certian rate 
    }
}

主要问题是 b1 和 b2 区块中的双倍利率美元，任何输出都将是无穷大的

我认为问题是执行顺序，但我不确定如何解决它