Servlet 配置文件web.xml

曾经终败给现在 2024-02-17 16:49 18阅读 0赞

一、配置文件如下：

<?xml version="1.0" encoding="UTF-8"?>
 <web-app version="3.0" 
 	xmlns="http://java.sun.com/xml/ns/javaee" 
 	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
 	xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
 	http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
 <display-name></display-name>
 
 
 <context-param>
 <param-name>names</param-name>
 <param-value>游将军</param-value>
 </context-param>
 
 <servlet>
 <description>This is the description of my J2EE component</description>
 <display-name>This is the display name of my J2EE component</display-name>
 <servlet-name>TestServlet</servlet-name>
 <servlet-class>com.hlx.test.TestServlet</servlet-class>
 
 <init-param>
 <param-name>username</param-name>
 <param-value>yjj</param-value>
 </init-param>
 </servlet>
 <servlet>
 <description>This is the description of my J2EE component</description>
 <display-name>This is the display name of my J2EE component</display-name>
 <servlet-name>LoginServlet</servlet-name>
 <servlet-class>com.hlx.login.LoginServlet</servlet-class>
 </servlet>
 
 
 <servlet-mapping>
 <servlet-name>TestServlet</servlet-name>
 <url-pattern>/test</url-pattern> 
 </servlet-mapping>
 
 <servlet-mapping>
 <servlet-name>LoginServlet</servlet-name>
 <url-pattern>/*</url-pattern>
 </servlet-mapping>	
 </web-app>

二、TestServlet页面

public class TestServlet extends HttpServlet {
 
 	/**
 	 * Constructor of the object.
 	 */
 	public TestServlet() {
 		super();
 		System.out.println("实例化对象！");
 	}
 
 	/**
 	 * Destruction of the servlet. 
 	 */
 	public void destroy() {
 		super.destroy(); // Just puts "destroy" string in log
 		// Put your code here
 		System.out.println("被火化了！");
 	}
 
 	/**
 	 * The doGet method of the servlet. 
 	 * 相当于表单提交的默认格式：method="GET"
 	 * 
 	 * This method is called when a form has its tag value method equals to get.
 	 * 
 	 * @param request
 	 * the request send by the client to the server
 	 * @param response
 	 * the response send by the server to the client
 	 * @throws ServletException
 	 * if an error occurred
 	 * @throws IOException
 	 * if an error occurred
 	 */
 	public void doGet(HttpServletRequest request, HttpServletResponse response)
 			throws ServletException, IOException {
 
 		// 解决乱码问题-->响应的编码
 		response.setContentType("text/html;charset=utf-8");
 		PrintWriter out = response.getWriter();
 
 		System.out.println("处理doGet方法!");
 
 		out.println("欢迎使用~==>" + this.getInitParameter("username") + "!");
 
 		// 调用全局配置参数值
 		String uname = this.getServletContext().getInitParameter("names");
 		//out.println(uname);
 		
 		//保存值
 		request.setAttribute("unames", uname);
 		//间接跳转 -->转发
 		//request.getRequestDispatcher("login").forward(request, response);
 		
 		//直接跳转-->重定向
 		//保存值 application 全局所有的页面有效;
 		//获得session对象
 		HttpSession session= request.getSession();
 		session.setAttribute("usession", uname);
 		
 		//获得application对象 全局所有的页面有效;
 		ServletContext	application = this.getServletContext();
 		application.setAttribute("uapp", uname);
 		
 	
 	//	response.sendRedirect("login");
 		
 		
 		
 		out.println("请求路径："+request.getContextPath());
 		out.println("请求方法："+request.getMethod());
 		out.println("请求Addr："+request.getLocalAddr());
 		out.println("请求post："+request.getLocalPort());
 		out.println("请求Name："+request.getLocalName());
 		out.println("请求Addr："+request.getRemoteAddr());
 		out.println("请求URI："+request.getRequestURI());
 		
 		
 		out.flush();
 		out.close();
 	}
 
 	/**
 	 * The doPost method of the servlet. 
 	 * 表单写提交方式：method="post"
 	 * 
 	 * This method is called when a form has its tag value method equals to
 	 * post.
 	 * 
 	 * @param request
 	 * the request send by the client to the server
 	 * @param response
 	 * the response send by the server to the client
 	 * @throws ServletException
 	 * if an error occurred
 	 * @throws IOException
 	 * if an error occurred
 	 */
 	public void doPost(HttpServletRequest request, HttpServletResponse response)
 			throws ServletException, IOException {
 
 		response.setContentType("text/html");
 		PrintWriter out = response.getWriter();
 		out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
 		out.println("<HTML>");
 		out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
 		out.println(" <BODY>");
 		out.print(" This is ");
 		out.print(this.getClass());
 		out.println(", using the POST method");
 		out.println(" </BODY>");
 		out.println("</HTML>");
 		out.flush();
 		out.close();
 	}
 
 	/**
 	 * Initialization of the servlet. 
 	 * 
 	 * @throws ServletException
 	 * if an error occurs
 	 */
 	public void init() throws ServletException {
 		// Put your code here
 		System.out.println("初始化！");
 	}
 
 }