jsp Request获取url信息的各种方法对比

湛蓝之海

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:/WebDemo 
basePath:https://localhost:8683/WebDemo/ 
remoteAddr:127.0.0.1 
servletPath:/index.jsp 
realPath:D:\apache-tomcat-6.0.13\webapps\WebDemo\ 
remoteUser:null 
requestURI:/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：https://localhost:8080/uploading/load.jsp  

request.getContextPath() => /uploading 
request.getServletPath() => /load.jsp 
request.getRequestURL() => https://localhost:8080/uploading/load.jsp 
request.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. https://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
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(); 
ring fullPath = url + queryString;  // 或者是url_buffer.toString()+queryString;

以上就是小编为大家带来的jsp Request获取url信息的各种方法对比的全部内容了，希望对大家有所帮助，多多支持CodeAE代码之家~