显示Servlet API主要版本，次要版本以及服务器系统信息
1 package com.mhb; 2 3 import java.io.IOException; 4 import java.io.PrintWriter; 5 6 import javax.servlet.ServletContext; 7 import javax.servlet.ServletException; 8 import javax.servlet.http.HttpServlet; 9 import javax.servlet.http.HttpServletRequest; 10 import javax.servlet.http.HttpServletResponse; 11 12 public class ServletContextDemo extends HttpServlet { 13 14 public void init() throws ServletException { 15 } 16 17 public void doGet(HttpServletRequest request, HttpServletResponse response) 18 throws ServletException, IOException { 19 //设置输出内容格式和编码 20 response.setContentType("text/html;charset=gb2312"); 21 PrintWriter out = response.getWriter(); 22 //获得ServletContext实例 23 ServletContext application = getServletContext(); 24 //主要的Servlet API版本 25 int magorVersion = application.getMajorVersion(); 26 //次要的Servlet api版本 27 int minorVersion = application.getMinorVersion(); 28 //服务器版本 29 String info = application.getServerInfo(); 30 31 out.println("<html>"); 32 out.println("<body>"); 33 out.println("主要Servlet API版本："+magorVersion+"<br />"); 34 out.println("次要Servlet API版本："+minorVersion+"<br />"); 35 out.println("服务器版本："+info+"<br />"); 36 out.println("</body>"); 37 out.println("</html>"); 38 39 } 40 41 public void doPost(HttpServletRequest request, HttpServletResponse response) 42 throws ServletException, IOException { 43 } 44 45 public void destroy() { 46 super.destroy(); 47 } 48 }
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