Cannot refer to a non-final variable * inside an inner class defined in a different method错误问题

在使用Java局部内部类或者匿名内部类时，若该类调用了所在方法的局部变量，则该局部变量必须使用final关键字来修饰，否则将会出现编译错误“Cannot refer to a non-final variable * inside an inner class defined in a different method”

例如：

public void commRequest(Context ctx, String apiUri, HashMap<String, String> pairs,
    final ApiCallback callback) {
  HttpCallParam params = new HttpCallParam();
  params.setUri(apiUri);
  params.setPairs(pairs);
  
  System.out.println("-apiUri---"+params.getUri());

  Handler handler = new Handler(new Handler.Callback() {

   @Override
   public boolean handleMessage(Message msg) {
    
    System.out.println("-msg.arg1---"+msg.arg1);
    
    
    if (msg.arg1 == HttpRequestService.MSG_ARG1_OK) {
     if (msg.arg2 == HttpRequestService.MSG_ARG2_STR) {
      callback.onError(msg.arg1, (String) msg.obj);
      //如果callback不是final定义，就会报错
     } else {
      JSONObject json = (JSONObject) msg.obj;
      String emsg = json.getString("errorMessage");
      int ecode = json.getIntValue("errorCode");
      callback.onSuccess(json, ecode, emsg);
     }
    } else {
     if (BuildConfig.DEBUG) {Log.v("LX", "请求失败,可能网络不畅");}
     callback.onError(msg.arg1, "请求失败,可能网络不畅");
    }
    return true;
   }
  });

  request(ctx, params, handler);
}