1 @WebServlet("/RequestDemo2")
2 public class RequestDemo2 extends HttpServlet {
3 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
4
5 }
6
7 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
8 //演示获取请求头数据
9
10 //1.获取所有请求头名称
11 Enumeration<String> headerNames = request.getHeaderNames();
12 //2.遍历
13 while(headerNames.hasMoreElements()){
14 String name = headerNames.nextElement();
15 //通过请求头的名称获取请求头的值
16 String value = request.getHeader(name);
17 System.out.println(name+"----"+value);
18 }
19 }
20 }
1 @WebServlet("/RequestDemo3")
2 public class RequestDemo3 extends HttpServlet {
3 protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
4
5 }
6
7 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
8 //演示获取请求头数据：user-agent
9 String agent = request.getHeader("user-agent");
10 //判度agent的浏览器版本
11 if(agent.contains("Chrome")){
12 //谷歌
13 System.out.println("谷歌。。。。");
14 }else if (agent.contains("Firefox")){
15 System.out.println("火狐。。。");
16 }
17
18
19 }
20 }
@WebServlet("/RequestDemo4")
public class RequestDemo4 extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//演示获取请求头数据：referer
String referer = request.getHeader("referer");
System.out.println(referer);
//防盗链
if(referer != null){
if(referer.contains("/request")){
//正常访问
// System.out.println("正常访问");
//显示中文
response.setContentType("text/html;charset=utf-8");
response.getWriter().write("正常访问");
}else{
//盗链
//System.out.println("盗链");
response.setContentType("text/html;charset=utf-8");
response.getWriter().write("存在盗链，不允许访问");
}
}
}
}