HttpServletRequest获取请求路径

HttpServletRequest获取请求路径
1、        //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.  /ser.do?method=add_pre&type=mad
        String url = request.getRequestURI();  
	return /ssm/ser.do
2、        //The returned URL contains a protocol, server name, port number, and server path, but it does not include query string parameters
          //eg.      http://localhost:8080/ssm/ser.do?method=add_pre&type=mad
        StringBuffer url_buffer = request.getRequestURL();
	return http://localhost:8080/ssm/ser.do

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;
即 /ssm/ser.do + method=add_pre&type=mad