首页编写一个Servlet，使程序能读取该Servlet的配置信息（使用ServletConfig），从中获得参数名为username,password,role对应的参数值，并输出到页面上。建议使用:<init-param>

编写一个Servlet，使程序能读取该Servlet的配置信息（使用ServletConfig），从中获得参数名为username,password,role对应的参数值，并输出到页面上。建议使用:<init-param>

时间: 2024-05-05 19:16:44 浏览: 49

在web.xml文件中配置参数，示例如下： ```xml <servlet> <servlet-name>MyServlet</servlet-name> <servlet-class>com.example.MyServlet</servlet-class> <init-param> <param-name>username</param-name> <param-value>admin</param-value> </init-param> <init-param> <param-name>password</param-name> <param-value>123456</param-value> </init-param> <init-param> <param-name>role</param-name> <param-value>administrator</param-value> </init-param> </servlet> ``` 然后在Servlet中使用ServletConfig获取参数值并输出到页面上，示例如下： ```java public class MyServlet extends HttpServlet { private String username; private String password; private String role; @Override public void init(ServletConfig config) throws ServletException { super.init(config); username = config.getInitParameter("username"); password = config.getInitParameter("password"); role = config.getInitParameter("role"); } @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=UTF-8"); PrintWriter out = response.getWriter(); out.println("<html>"); out.println("<head>"); out.println("<title>Servlet Configuration</title>"); out.println("</head>"); out.println("<body>"); out.println("<h2>Servlet Configuration Parameters:</h2>"); out.println("<p>Username: " + username + "</p>"); out.println("<p>Password: " + password + "</p>"); out.println("<p>Role: " + role + "</p>"); out.println("</body>"); out.println("</html>"); out.close(); } } ```

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