jsp request 获取路径

这篇教程不错：http://zjutsoft.iteye.com/blog/1084260

自己试验如下：

System.out.println("-----------------servlet-----------------");
System.out.println("realpath null:"+request.getRealPath(""));
System.out.println("realpath index.jsp:"+request.getRealPath("index.jsp"));
System.out.println("realpath ./:"+request.getRealPath("./"));
System.out.println("realpath ../:"+request.getRealPath("../"));
System.out.println("contextpath:"+request.getContextPath());
System.out.println("web项目的全路径:"+request.getSession().getServletContext().getRealPath("/"));
System.out.println("URI:"+request.getRequestURI());
System.out.println("URL:"+request.getRequestURL());
System.out.println("servletpath:"+request.getServletPath());
//System.out.println("页面在服务器的绝对路径:"+new java.io.File(application.getRealPath(request.getRequestURI())).getParent());

System.out.println("~~~~~~~~~~~~~~~页面~~~~~~~~~~~~~~~~~");
System.out.println("realpath null:"+request.getRealPath(""));
System.out.println("realpath index.jsp:"+request.getRealPath("index.jsp"));
System.out.println("realpath ./:"+request.getRealPath("./"));
System.out.println("realpath ../:"+request.getRealPath("../"));
System.out.println("contextpath:"+request.getContextPath());
System.out.println("web项目的全路径:"+request.getSession().getServletContext().getRealPath("/"));
System.out.println("URI:"+request.getRequestURI());
System.out.println("URL:"+request.getRequestURL());
System.out.println("servletpath:"+request.getServletPath());
System.out.println("页面在服务器的绝对路径:"+new java.io.File(application.getRealPath(request.getRequestURI())).getParent());

//结果
-----------------servlet-----------------
realpath null:D:eclipse-jee-luna-SR1-win32eclipseworkspace.metadata.pluginsorg.eclipse.wst.server.core	mp0wtpwebappsjyxt
realpath index.jsp:D:eclipse-jee-luna-SR1-win32eclipseworkspace.metadata.pluginsorg.eclipse.wst.server.core	mp0wtpwebappsjyxtindex.jsp
realpath ./:D:eclipse-jee-luna-SR1-win32eclipseworkspace.metadata.pluginsorg.eclipse.wst.server.core	mp0wtpwebappsjyxt.
realpath ../:D:eclipse-jee-luna-SR1-win32eclipseworkspace.metadata.pluginsorg.eclipse.wst.server.core	mp0wtpwebappsjyxt..
contextpath:/jyxt
web项目的全路径:D:eclipse-jee-luna-SR1-win32eclipseworkspace.metadata.pluginsorg.eclipse.wst.server.core	mp0wtpwebappsjyxt
URI:/jyxt/hello
URL:http://localhost:8080/jyxt/hello
servletpath:/hello
~~~~~~~~~~~~~~~页面~~~~~~~~~~~~~~~~~
realpath null:D:eclipse-jee-luna-SR1-win32eclipseworkspace.metadata.pluginsorg.eclipse.wst.server.core	mp0wtpwebappsjyxt
realpath index.jsp:D:eclipse-jee-luna-SR1-win32eclipseworkspace.metadata.pluginsorg.eclipse.wst.server.core	mp0wtpwebappsjyxtindex.jsp
realpath ./:D:eclipse-jee-luna-SR1-win32eclipseworkspace.metadata.pluginsorg.eclipse.wst.server.core	mp0wtpwebappsjyxt.
realpath ../:D:eclipse-jee-luna-SR1-win32eclipseworkspace.metadata.pluginsorg.eclipse.wst.server.core	mp0wtpwebappsjyxt..
contextpath:/jyxt
web项目的全路径:D:eclipse-jee-luna-SR1-win32eclipseworkspace.metadata.pluginsorg.eclipse.wst.server.core	mp0wtpwebappsjyxt
URI:/jyxt/WEB-INF/view/index.jsp
URL:http://localhost:8080/jyxt/WEB-INF/view/index.jsp
servletpath:/WEB-INF/view/index.jsp
页面在服务器的绝对路径:D:eclipse-jee-luna-SR1-win32eclipseworkspace.metadata.pluginsorg.eclipse.wst.server.core	mp0wtpwebappsjyxtjyxtWEB-INFview

在类中获取路径先不看，其他的只有10种方法。

两种应用场景：.jsp和servlet中。jsp中realPath被抛弃，不过返回值跟servlet中的一样，getRealPath("./   ../")返回值都不太对；页面在服务器的绝对路径 就不能用了。

getContextPath() 和 .getSession().getServletContext().getRealPath("/") 在.jsp和servlet中返回值都一样；URI,URL,servletpath都不一样。

//http
System.out.println("scheme:"+request.getScheme());
//localhost
System.out.println("name:"+request.getServerName());
//8080
System.out.println("port:"+request.getServerPort());

常用方法

在servlet中：getContextPath(), URI, URL, servletPath(), 
在jsp中：getContextPath()