什么是HttpServletRequest？

HttpServletRequest代表客戶端的請(qǐng)求，用戶通過(guò)Http協(xié)議訪問(wèn)服務(wù)器，HTTP請(qǐng)求中的所有信息會(huì)被封裝到HttpServletRequest，通過(guò)這個(gè)HttpServletRequest的方法，獲得客戶端的所有信息；

HttpServletRequest的使用

@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

    req.setCharacterEncoding("utf-8");
    resp.setCharacterEncoding("utf-8");

    String username = req.getParameter("username");
    String password = req.getParameter("password");
    String[] hobbys = req.getParameterValues("hobbys");
    System.out.println("=============================");
    //后臺(tái)接收中文亂碼問(wèn)題
    System.out.println(username);
    System.out.println(password);
    System.out.println(Arrays.toString(hobbys));
    System.out.println("=============================");


    System.out.println(req.getContextPath());
    //通過(guò)請(qǐng)求轉(zhuǎn)發(fā)
    //這里的 / 代表當(dāng)前的web應(yīng)用
    req.getRequestDispatcher("/success.jsp").forward(req,resp);

}