//1. 获取请求方式 :GET
String method = request.getMethod();
System.out.println(method);
//2.(*)获取虚拟目录:/day14
String contextPath = request.getContextPath();
System.out.println(contextPath);
//3. 获取Servlet路径: /demo1
String servletPath = request.getServletPath();
System.out.println(servletPath);
//4. 获取get方式请求参数:name=zhangsan
String queryString = request.getQueryString();
System.out.println(queryString);
//5.(*)获取请求URI:/day14/demo1
String requestURI = request.getRequestURI();
StringBuffer requestURL = request.getRequestURL();
System.out.println(requestURI);
System.out.println(requestURL);
//6. 获取协议及版本:HTTP/1.1
String protocol = request.getProtocol();
System.out.println(protocol);
//7. 获取客户机的IP地址:
String remoteAddr = request.getRemoteAddr();
System.out.println(remoteAddr);
获取请求头信息:
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//演示获取请求头数据
//1.获取所有请求头名称
Enumeration<String> headerNames = request.getHeaderNames();
//2.遍历
while(headerNames.hasMoreElements()){
String name = headerNames.nextElement();
//根据名称获取请求头的值
String value = request.getHeader(name);
System.out.println(name+"---"+value);
}
判断是哪个浏览器进行访问的:(不同的浏览器请求头user-agent不同)
String agent = request.getHeader("user-agent");
//判断agent的浏览器版本
if(agent.contains("Chrome")){
//谷歌
System.out.println("谷歌来了...");
}else if(agent.contains("Firefox")){
//火狐
System.out.println("火狐来了...");
}
防止盗链小案例
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);//http://localhost/day14/login.html
//防盗链
if(referer != null ){
if(referer.contains("/Yum")){
//正常访问
response.setContentType("text/html;charset=utf-8");
response.getWriter().write("播放电影....");
}else{
//盗链
response.setContentType("text/html;charset=utf-8");
response.getWriter().write("想看电影吗?来优酷吧...");
}
}
//根据参数名称获取参数值 用于提取用户名或者密码参数
String username = request.getParameter("username");
//根据参数名称获取参数值的数组 多选
String[] hobbies = request.getParameterValues("hobby");
//获取所有请求的参数名称
Enumeration<String> parameterNames = request.getParameterNames();
记住:
// 获取所有参数的map集合
Map<String, String[]> parameterMap = request.getParameterMap();
//遍历
Set<String> keyset = parameterMap.keySet();
for (String name : keyset) {
//获取键获取值
String[] values = parameterMap.get(name);
System.out.println(name);
for (String value : values) {
System.out.println(value);
}
//1.设置流的编码
request.setCharacterEncoding(“utf-8”);
ServletContext
域对象