request获取各种获取各种路径信息

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demo，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("remoteUser:"+remoteUser+"<br>");  
out.println("requestURI:"+requestURI+"<br>");  
结果：  
path:/demo  
basePath:http://localhost:8683/WebDemo/  
remoteAddr:127.0.0.1  
servletPath:/index.jsp  
remoteUser:null  
requestURI:/demo/index.jsp  

从上不难看出request各个对应方法所代表的含义