JSPconfig对象的使用.doc

config对象1、什么是config对象？(1) config对象：用于获取初始化参数。具体来说：如果在web.xml文件中，针对某个Servlet文件或JSP文件设置了初始化参数，则可以通过config对象来获取这些初始化参数。(2) config对象的基类是：javax.servlet.ServletConfig接口。(3) config对象的常用方法，如下所示：方法名描述String getInitParameter(String name)根据指定的初始化参数名称，获取对应的参数值。Enumeration getInitParameterNames()获取所有的初始化参数名称。ServletContext getServletContext()返回一个ServletContext接口的对象String getServletName()获取当前Servlet对象的名称。2、使用config对象获取初始化参数(1) 获取某个JSP文件的初始化参数测试代码TestConfig01.jsp客户服务信箱：客户服务热线：客户服务QQ号：修改web.xml文件，添加如下蓝色字体部分：当当网Logincom.niit.csmz.LoginResultcom.niit.csmz.Result admin /TestConfig01.jsp email phoneqq 88888 Login/Forward/servlet/LoginResult/servlet/Result admin /TestConfig01.jsp appName MyWebTest appVersion Version 1.0 index.jsp (2) 获取某个Servlet文件的初始化参数测试代码创建一个名为Config的Servlet文件，代码如下所示：package com.niit.csmz;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.ServletConfig;import java.io.PrintWriter;public class Config extends HttpServlet private static final long serialVersionUID = -623285226021156806L;public Config() super();public void init() throws ServletException super.init();public void destroy() super.destroy();public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException doPost(request, response);public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException ServletConfig sc = this.getServletConfig();String email = sc.getInitParameter(email);String phone = sc.getInitParameter(phone);String qq = sc.getInitParameter(qq);response.setContentType(text/html; charset=gb2312);PrintWriter pw = response.getWriter();pw.write(客户服务信箱： + email);pw.write(客户服务热线： + phone);pw.write(客户服务QQ号： + qq);修改web.xml文件，添加如下蓝色字体部分：当当网Logincom.niit.csmz.LoginResultcom.niit.csmz.Result admin /TestConfig01.jsp email phoneqq 88888 Config com.niit.csmz.Config email phoneqq 88888 Login/Forward/servlet/LoginResult/servlet/Result admin /TestConfig01.jsp Config /servlet/Config appName MyWebTest appVersion Version 1.0 index.jsp 3、application对象和config对象的区别 (1) 使