获取HttpServletRequest请求信息,HTTP协议信息

/**
 * HttpServletRequest请求参数获取测试
 * @author Niu on 2017年7月17日 下午2:45:01
 */
@WebServlet("/dispense")
public class DispenseServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 获取请求方式：GET
        System.out.println("req.getMethod():" + req.getMethod());

        // 获取项目名称：/dispense
        System.out.println("req.getContextPath():" + req.getContextPath());

        // 获取完整请求路径：http://localhost:8888/dispense/dispense
        System.out.println("req.getRequestURL():" + req.getRequestURL());

        // 获取除了域名外的请求数据：/dispense/dispense
        System.out.println("req.getRequestURI():" + req.getRequestURI());

        // 获取请求参数：name=codingme.net
        System.out.println("req.getQueryString():" + req.getQueryString());
        // 获取请求头：
        System.out.println("req.getHeader(\"user-Agent\"):" + req.getHeader("user-Agent"));

        System.out.println("--------------------------------------------------------");
        // 获取所有的消息头名称
        Enumeration<String> headerNames = req.getHeaderNames();
        // 获取获取的消息头名称，获取对应的值，并输出
        while (headerNames.hasMoreElements()) {
            String nextElement = headerNames.nextElement();
            System.out.println(nextElement + ":" + req.getHeader(nextElement));
        }

        System.out.println("----------------------------------------------------------");
        // 根据名称获取此重名的所有数据
        System.out.println("req.getHeader(\"accept\"):" + req.getHeader("accept"));

        // 获取请求主机名
        System.out.println("req.getHeader(\"host\"):" + req.getHeader("host"));

    }

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

req.getMethod():GET
req.getContextPath():/dispense
req.getRequestURL():http://localhost:8888/dispense/dispense
req.getRequestURI():/dispense/dispense
req.getQueryString():name=codingme.net
req.getHeader("user-Agent"):Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3080.5 Safari/537.36
--------------------------------------------------------
host:localhost:8888
connection:keep-alive
cache-control:max-age=0
upgrade-insecure-requests:1
user-agent:Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3080.5 Safari/537.36
accept:text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
accept-encoding:gzip, deflate, br
accept-language:zh-CN,zh;q=0.8
cookie:_ga=GA1.1.1003706294.1499565784; Hm_lvt_57ccbd5c600ed4e6bdb9458e666b6409=1499849256,1499853602,1499950574; Hm_lvt_1b51c3ea9a3e7b1a2bc55df97ab4efd3=1499952403
----------------------------------------------------------
req.getHeader("accept"):text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
req.getHeader("host"):localhost:8888