java如何跨包调用 java跨项目调用接口

public String load(String url, String query) throws Exception {
        URL restURL = new URL(url);
        /*
         * 此处的urlConnection对象实际上是根据URL的请求协议(此处是http)生成的URLConnection类 的子类HttpURLConnection
         */
        HttpURLConnection conn = (HttpURLConnection) restURL.openConnection();
        //请求方式
        conn.setRequestMethod("POST");
        //设置是否从httpUrlConnection读入，默认情况下是true; httpUrlConnection.setDoInput(true);
        conn.setDoOutput(true);
        //allowUserInteraction 如果为 true，则在允许用户交互（例如弹出一个验证对话框）的上下文中对此 URL 进行检查。
        conn.setAllowUserInteraction(false);

        PrintStream ps = new PrintStream(conn.getOutputStream());
        ps.print(query);
        ps.close();

        BufferedReader bReader = new BufferedReader(new InputStreamReader(conn.getInputStream()));

        String line, resultStr = "";

        while (null != (line = bReader.readLine())) {
            resultStr += line;
        }
        System.out.println("3412412---" + resultStr);
        bReader.close();
        return resultStr;
    }

public static void main(String[] args) {
        try {
            APIService restUtil = new APIService();
            String resultString = restUtil.load(
                    "http://**.**.**.**:8079/HouseLizardCloud/Message/ShortMessage",
                    "mobile=177198****&codeType=2");
        } catch (Exception e) {
            e.printStackTrace();
            System.out.print(e.getMessage());
        }
    }
}