Question

如何在注释中为web.XML提供注释映射。我已经完成了web.XML。一世想尝试使用注释映射，如下所示：

<web-app> 
  <servlet-mapping> 
  </servlet-mapping> 
</web-app>

Answer 1

一个简单的例子是：

@WebServlet(value="/hello")
public class HelloServlet extends HttpServlet {

    @Override
    public void doGet(HttpServletRequest request,HttpServletResponse response)
        throws ServletException, IOException {
    PrintWriter out = response.getWriter();

    // then write the data of the response
    String username = request.getParameter("username");
    if (username != null && username.length() > 0) {
        out.println("<h2>Hello, " + username + "!</h2>");
       }
    }

}

Answer 2

Annotation 表示元数据。如果使用注释，则不需要部署描述符（web.xml文件）。但你应该有tomcat7，因为它不会在以前版本的tomcat中运行。 @WebServlet注释用于映射具有指定名称的servlet。

@WebServlet("/Simple")
public class Simple extends HttpServlet {
    private static final long serialVersionUID = 1L;

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {


        response.setContentType("text/html");
        PrintWriter out=response.getWriter();

        out.print("<html><body>");
        out.print("<h3>Hello Servlet</h3>");
        out.print("</body></html>");
    }

}

如何在servlet中使用注释而不是web.xml来指定url

2 个答案: