Request获取url信息的各种方法比较
从Request对象中可以获取各种路径信息，以下例子：假设请求的页面是index.jsp,项目是WebDemo，则在index.jsp中获取有关request对象的各种路径信息如下String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";String remoteAddress=request.getRemoteAddr();String servletPath=request.getServletPath();String realPath=request.getRealPath("/");String remoteUser=request.getRemoteUser();String requestURI=request.getRequestURI();out.println("path:"+path+"<br>");out.println("basePath:"+basePath+"<br>");out.println("remoteAddr:"+remoteAddress+"<br>");out.println("servletPath:"+servletPath+"<br>");out.println("realPath:"+realPath+"<br>");out.println("remoteUser:"+remoteUser+"<br>");out.println("requestURI:"+requestURI+"<br>");结果：path:/WebDemobasePath:http://localhost:8683/WebDemo/remoteAddr:127.0.0.1servletPath:/index.jsprealPath:D:\apache-tomcat-6.0.13\webapps\WebDemo\remoteUser:nullrequestURI:/WebDemo/index.jsp从上不难看出request各个对应方法所代表的含义从request获取各种路径总结：request.getRealPath("url");//虚拟目录映射为实际目录request.getRealPath("./");//网页所在的目录request.getRealPath("../");//网页所在目录的上一层目录假定你的web application(web应用)名称为news，你的浏览器中输入请求路径：http://localhost:8080/uploading/load.jsprequest.getContextPath() => /uploadingrequest.getServletPath() => /load.jsprequest.getRequestURL() => http://localhost:8080/uploading/load.jsprequest.getRealPath("/") => F:\learn\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps\uploading\现在request.getRealPath("/") 这个方法已经不推荐使用了可以使用ServletContext.getRealPath(java.lang.String) instead.request.getSession().getServletContext().getRealPath() 得到工程文件的实际物理路径,也就是绝对地址//Returns the part of this request's URL from the protocol name up to the query string in the first line of the HTTP request // eg. /manage/editExam.domethod=goExamSet&type=U String url = request.getRequestURI(); //The returned URL contains a protocol, server name, port number, and server path, but it does not include query string parameters //eg. http://127.0.0.1:8080/manage/editExam.domethod=goExamSet&type=U StringBuffer url_buffer = request.getRequestURL(); HttpServletRequest 的这两种方法都只能得到不包含参数的请求url，区别如下： 1 前者返回相对路径，后者返回完整路径 2 前者返回string ，后者返回stringbuffer要想得到完整请求url可以通过如下方法，getQueryString()得到的是url后面的参数串，和前者相加就是带参数的请求路径了 String queryString = request.getQueryString();String fullPath = url + queryString; // 或者是url_buffer.toString()+queryString;