web.xml配置参数context-param和init-param的区别
web.xml配置参数context-param和init-param的区别web.xml里面可以定义两种参数：
(1)application范围内的参数，存放在servletcontext中，在web.xml中配置如下：<context-param> <param-name>context/param</param-name> <param-value>avalible during application</param-value> </context-param>

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(2)servlet范围内的参数，只能在servlet的init()方法中取得，在web.xml中配置如下：

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<servlet> <servlet-name>MainServlet</servlet-name> <servlet-class>com.wes.controller.MainServlet</servlet-class> <init-param> <param-name>param1</param-name> <param-value>avalible in servlet init()</param-value> </init-param> <load-on-startup>0</load-on-startup> </servlet>

?在servlet中可以通过代码分别取用：

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package com.wes.controller; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; public class MainServlet extends HttpServlet{ public MainServlet(){ super(); } public void init() throws ServletException ...{ System.out.println("下面的两个参数param1是在servlet中存放的"); System.out.println(this.getInitParameter("param1")); System.out.println("下面的参数是存放在servletcontext中的"); System.out.println(getServletContext().getInitParameter("context/param")); } }

?第一种参数在servlet里面可以通过getServletContext().getInitParameter("context/param")得到

在JSP中可以用config.getServletContext().getInitParameter("context/param")得到

或者this.getServletContext().getInitParameter("context/param")


第二种参数只能在servlet的init()方法中通过this.getInitParameter("param1")取得.