Request请求参数解析

get方式和post方式可以统一解析，doPost方式转给doGet方式使用getParameterMap()转为Map解析。

@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        Map<String, String[]> map = req.getParameterMap();
        for (String key : map.keySet()) {

            System.out.print(key + ":");

            String[] values = map.get(key);
            for (String value : values) {
                System.out.print(value + " ");
            }
            System.out.println();
        }
        //System.out.println(map);
        //System.out.println(map.get("username"));
}

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

获取所有参数集合
Map<String, String[]> map = req.getParameterMap();

获取单个参数的值【返回单个数值】
String uName = req.getParameter("name");

获取参数的值【返回数组】
String[] uNames = req.getParameterValues("names");

请求中文乱码
解决post方式请求方式

req.setCharacterEncoding("UTF-8");
String username = req.getParameter("username");
System.out.println("姓名：" + username);