Servlet的Request中和用户请求路径相关的操作有多个(网络整理)
Servlet的Request中和用户请求路径相关的操作有多个，下面一一列举：
1.getQueryString()，&之后GET方法的参数部分。
2.getServletPath()，web.xml中定义的Servlet访问路径。
3.getPathInfo()，Servlet访问路径之后，QueryString之前的中间部分。
4.getContextPath()，Context路径前缀（这个应该是最熟悉的啦）。
5.getRequestURI()，等于getContextPath() + getServletPath() + getPathInfo()。
6.getRequestURL()，等于getScheme() + "://" + getServerName() + ":" + getServerPort() + getRequestURI()。
7.getPathTranslated()，等于getServletContext().getRealPath("/") + getPathInfo()。
注意：
1.getServletContext().getRealPath("/") 后包含当前系统的文件夹分隔符（windows系统是""，linux系统是"/"），而getPathInfo()以"/"开头。
request对象中的方法是比较实用的，大家应该对它们都有所了解。下面我们通过一个TestServlet来讲解一下常用的方法。TestServlet源代码如下： package coresun;import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class TestServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException { response.setContentType("text/html;charset=gb2312"); PrintWriter out = response.getWriter(); out.println("<html><head><title>使用request中的方法</title></head><body><h2>"); out.println("request.getRequestURL()= "+request.getRequestURL()+"<br>"); out.println("request.getRequestURI()= "+request.getRequestURI()+"<br>"); out.println("request.getContextPath()= "+request.getContextPath()+"<br>"); out.println("request.getServletPath()= "+request.getServletPath()+"<br>"); out.println("request.getQueryString()= "+request.getQueryString()+"<br>"); out.println("request.getPathInfo()= "+request.getPathInfo()+"<br>"); out.println("request.getPathTranslated()= "+request.getPathTranslated()); out.println("<br>"); out.println("request.getProtocol()= "+request.getProtocol()+"<br>"); out.println("request.getMethod()= "+request.getMethod()+"<br>"); out.println("request.getScheme()= "+request.getScheme()+"<br>"); out.println("request.getRequestedSessionId()= "+request.getRequestedSessionId()+"<br>"); out.println("request.isRequestedSessionIdFromCookie()= "+request.isRequestedSessionIdFromCookie()+"<br>"); out.println("request.isRequestedSessionIdFromURL()= "+request.isRequestedSessionIdFromURL()+"<br>"); out.println("request.isRequestedSessionIdValid()= "+request.isRequestedSessionIdValid()+"<br>"); out.println("</h2></body></html>"); } }此Servlet在web.xml文件中的部署如下：（只有关键代码）<servlet> <servlet-name>test</servlet-name> <servlet-class>coresun.TestServlet</servlet-class></servlet><servlet-mapping> <servlet-name>test</servlet-name> <url-pattern>*.do</url-pattern></servlet-mapping>*.do表示只要是以.do结尾的地址，都可以访问此Servlet。然后在地址栏中输入如下网址：(假设服务器为本地，端口8080，Web根目录为FilterWeb)http://localhost:8080/FilterWeb/update.do?userName=zhangsan&age=20页面返回的结果如下：request.getRequestURL() = http://localhost:8080/FilterWeb/update.dorequest.getRequestURI() = /FilterWeb/update.dorequest.getContextPath() = /FilterWebrequest.getServletPath() = /update.dorequest.getQueryString() = userName=zhangsan&age=20request.getPathInfo() = nullrequest.getPathTranslated() = nullrequest.getProtocol() = HTTP/1.1request.getMethod() = GETrequest.getScheme() = httprequest.getRequestedSessionId() = 0D5219B7FF11D47EBE95B2E6A31076B5request.isRequestedSessionIdFromCookie() = truerequest.isRequestedSessionIdFromURL() = falserequest.isRequestedSessionIdValid() = truerequest.getAuthType() = null这些方法的含义大家通过它的名字应该能够揣摩出来的。下面更改servlet的url-pattern地址,如下：<servlet> <servlet-name>test</servlet-name> <servlet-class>coresun.TestServlet</servlet-class></servlet><servlet-mapping> <servlet-name>test</servlet-name> <url-pattern>/faces/*</url-pattern></servlet-mapping>以上表示只要是以/faces/开头的地址，此Servlet都可以访问浏览器的地址栏中填入如下地址：http://localhost:8080/FilterWeb/faces/update?userName=zhangsan&age=20页面返回的结果如下：request.getRequestURL() = http://localhost:8080/FilterWeb/faces/updaterequest.getRequestURI() = /FilterWeb/faces/updaterequest.getContextPath() = /FilterWebrequest.getServletPath() = /facesrequest.getQueryString() = userName=zhangsan&age=20request.getPathInfo() = /updaterequest.getPathTranslated() = D:\FilterProject\FilterWeb\updaterequest.getProtocol() = HTTP/1.1request.getMethod() = GETrequest.getScheme() = httprequest.getRequestedSessionId() = 0D5219B7FF11D47EBE95B2E6A31076B5request.isRequestedSessionIdFromCookie() = truerequest.isRequestedSessionIdFromURL() = falserequest.isRequestedSessionIdValid() = truerequest.getAuthType() = null?