//        getMethod(); 获得请求方式
//        ***getRequestURL();返回客户端发出请求时的完整URL。
//        ***getRequestURI(); 返回请求行中的资源名部分。
//        *****getContextPath(); 当前应用的虚拟目录 /day09_01_HttpServletRequest
//        getQueryString() ; 返回请求行中的参数部分。
        
        System.out.println(request.getMethod());//  GET
        System.out.println(request.getRequestURL()); // http://localhost:8080/day09_01_HttpServletRequest/servlet/demo1
        System.out.println(request.getRequestURI()); //   /day09_01_HttpServletRequest/servlet/demo1
        System.out.println(request.getContextPath()); //  /day09_01_HttpServletRequest
        System.out.println(request.getQueryString()); //  username=tom

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //1.统一资源标记符   /Web_Servlet/ServletTest3
        String uri = req.getRequestURI();
        System.out.println(uri);
        //2.统一资源定位符    http://localhost:6060/Web_Servlet/ServletTest3 
        StringBuffer url = req.getRequestURL();
        System.out.println(url);
        //3.协议和版本    HTTP/1.1
        String potocol = req.getProtocol();
        System.out.println(potocol);
        //4.协议    http
        String scheme = req.getScheme();
        System.out.println(scheme);
        //5.主机（域名）  localhost,如果你使用的是ip地址，就显示ip地址
        String serverName = req.getServerName();
        System.out.println(serverName);
        //6.端口  6060(这是我自己修改了的端口，默认是8080)
        int port = req.    getServerPort();
        System.out.println(port);
        //7.发布到tomcat下的项目名称  /Web_Servlet
        String contextPath = req.getContextPath();
        System.out.println(contextPath);
        //8.servlet路径    /ServletTest3 
        String servletPath = req.getServletPath();
        System.out.println(servletPath);
        //9.获取所有请求参数，即?之后所有东西。    username=faker&password=mid
        String queryString = req.getQueryString();
        System.out.println(queryString);
        //10.远程主机的ip地址    0:0:0:0:0:0:0:1
        String remoteAddr = req.getRemoteAddr();
        System.out.println(remoteAddr);
        
        
    }

<form action="/day09_01_HttpServletRequest/servlet/demo3" method="get">
        用户名：<input type="text" name="userName"/><br/>
        密码：<input type="password" name="pwd"/><br/>
        性别：<input type="radio" name="sex" value="男" checked="checked"/>男  
            <input type="radio" name="sex" value="女"/>女  <br/>
        爱好 ：
            <input type="checkbox" name="hobby" value="篮球"/>篮球
            <input type="checkbox" name="hobby" value="唱歌"/>唱歌
            <input type="checkbox" name="hobby" value="编码"/>编码
            <br/>
        所在城市：
        <select name="city">
            <option>------请选择------</option>
            <option value="bj">北京</option>
            <option value="sh">上海</option>
            <option value="gz">广州</option>
        </select>
        <br/>
        
        <input type="submit" value="注册"/>
    </form>

//获取表单数据
        
        //根据表单中name属性的名，获取value属性的值方法 
        String userName = request.getParameter("userName");
        String pwd = request.getParameter("pwd");
        String sex = request.getParameter("sex");
        String[] hobbys = request.getParameterValues("hobby");
        
        String city = request.getParameter("city");
        
        userName = new String(userName.getBytes("iso-8859-1"),"UTF-8");
        System.out.println(userName);
        System.out.println(pwd);
        System.out.println(sex);
        
        for (int i = 0;hobbys!=null && i < hobbys.length; i++) {
            System.out.print(hobbys[i]+"\t");
        }
        System.out.println();
        
        System.out.println(city);

//获取所有的表单name的名子
        Enumeration names = request.getParameterNames();
        while(names.hasMoreElements()){
            String name = (String) names.nextElement();//得到每一个name名
            String[] values = request.getParameterValues(name);//根据name名，得到value值
            for (int i = 0;values!=null && i < values.length; i++) {
                System.out.println(name+"\t"+values[i]);

try {
            User u = new User();
            System.out.println("封装数据前："+u);
            //获取表单数据
            Map<String,String[]> map = request.getParameterMap();
            
            for (Map.Entry<String, String[]> m : map.entrySet()) {
                String name = m.getKey();
                String[] value = m.getValue();
                
                //创建一属性描述器
                PropertyDescriptor pd = new PropertyDescriptor(name, User.class);
                //得到setter属性
                Method setter = pd.getWriteMethod();
                
                if(value.length==1){
                    setter.invoke(u, value[0]);//给一个值的变量赋值
                }else{
                    setter.invoke(u, (Object)value);//相关于给复选框赋值
                }
            }
            
            System.out.println("封装数据后："+u);
        } catch (Exception e) {
            e.printStackTrace();
        }

request.setCharacterEncoding("UTF-8");
        //获取表单数据
        ServletInputStream sis = request.getInputStream();
        int len = 0;
        byte[] b = new byte[1024];
        while((len=sis.read(b))!=-1){
            //System.out.println(new String(new String(b,0,len).getBytes(),"utf-8"));
            System.out.println(new String(b, 0, len, "UTF-8"));
        }
        
        sis.close();