How to convert web.xml to @WebServlet?

Question

I have a web application with servlet 3.1 and have servlet filter without @WebFilter annotation and its working fine.

I want to replace it with @WebServlet annotation but using same old filter without creating new filter class and using @WebFilter in the old filter class. Below is my web.xml file.

<web-app version="3.1"
         xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
         http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd">
  <display-name>Archetype Created Web Application</display-name>
    <filter>
        <display-name>User Auth Filter</display-name>
        <filter-name>UserAuthFilter</filter-name>
        <filter-class>com.example.UserAuthFilter</filter-class>
        <async-supported>true</async-supported>
        <init-param>
            <param-name>checkUser</param-name>
            <param-value>true</param-value>
        </init-param>
        <init-param>
            <param-name>doValidate</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
   <filter-mapping>
        <filter-name>UserAuthFilter</filter-name>
        <url-pattern>/usercount</url-pattern>
    </filter-mapping>
    <security-constraint>
        <web-resource-collection>
            <web-resource-name>Services</web-resource-name>
            <url-pattern>/usercount</url-pattern>
            <http-method>GET</http-method>
        </web-resource-collection>
    </security-constraint>
    <deny-uncovered-http-methods/>
</web-app>

and I tried to replace it with below servlet.

package com.example;

import javax.servlet.annotation.WebFilter;
import javax.servlet.annotation.WebInitParam;
import javax.servlet.annotation.WebServlet;

@WebServlet
@WebFilter(displayName = "User Auth Filter",
        filterName = "UserAuthFilter",
        value = "com.example.UserAuthFilter",
        asyncSupported = true,
        initParams = {
                @WebInitParam(name = "checkUser",value = "true"),
                @WebInitParam(name = "doValidate",value = "true")
        })
public class NotificationWebsocketServlet {
    public NotificationWebsocketServlet() {
        super();
        // TODO Auto-generated constructor stub
    }
}

I did not find any annotation for filter-mapping and security-constraint.

Could you help me on this?

score 0 · Accepted Answer · answered Apr 26 '18 at 17:20

0

For the @WebFilter you should be able to use the urlPatterns attribute for the filter mapping. In addition you should be able to use @ServletSecurity annotation for your security-constraint.

answered Apr 26 '18 at 17:20

Paul Nicolucci

113
4

Thanks @Paul is the value for filter name is correct as servlet filter class(com.example.UserAuthFilter)? – Passionate developer Apr 26 '18 at 18:14
The @WebFilter annotation should actually be on the class that is the Filter. The "values" or "urlPatterns" attributes can be used for the mapping. Oracle has some good tutorials for EE technologies: https://docs.oracle.com/javaee/7/tutorial/servlets006.htm – Paul Nicolucci Apr 26 '18 at 19:21

How to convert web.xml to @WebServlet?

1 Answers1