servletContext读取全局参数核心方法

　　getServletContext().getInitParameter(name);//根据指定的参数名获取参数值

　　1.      在web.xml中配置全局参数

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="4.0" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee                       http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd">
	<context-param>
	    <param-name>company</param-name>
	    <param-value>南昌雅腾</param-value>
  	</context-param>
</web-app>

　　2.      在动态资源servlet里面使用servletcontext读取全局参数代码

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		//response.getWriter().append("Served at: ").append(request.getContextPath());
		response.setContentType("text/html;charset=UTF-8");
		PrintWriter out = response.getWriter();
		ServletContext context = request.getServletContext();
		out.println(context.getInitParameter("company"));
		context.setAttribute("names", "庄子");  //同时可以设置属性
		out.println(context.getAttribute("names"));
	}

结果如下：

JSP文件读取web.xml配置参数

<%out.println(request.getServletContext().getAttribute("names"));
      out.println(request.getServletContext().getInitParameter("company"));
    %>