public int loadingFinishedCount(WebDriver driver){
        LogEntries logs = driver.manage().logs().get("performance");
//        System.out.println("\nList of log entries:\n");
        int m=0;
        for(Iterator<LogEntry> it = logs.iterator(); it.hasNext();){
            LogEntry entry = it.next();
            try{
                JSONObject json = new JSONObject(entry.getMessage());
                JSONObject message = json.getJSONObject("message");
//                System.out.println(message);
                String method = message.getString("method");
                if(method!=null&&"Network.loadingFinished".equals(method)){
                    ++m;
                }
            }catch (JSONException e){
                e.printStackTrace();
            }
        }
        return m;
    }

    public void pageLoadingFinished(WebDriver driver, int loadingFinishedCount){
        loadingFinishedCount(driver);
//        System.out.println(m);
        for(double i=0; i<=1000; i=i+0.1) {
            int n = loadingFinishedCount(driver);
//            System.out.println(n);
            if (n >=loadingFinishedCount) {
                break;
            }
        }
    }

reference:https://*.com/questions/6509628/how-to-get-http-response-code-using-selenium-webdriver-with-java