Question

I am trying to add another filter named captcha verification filter along with spring security’s authentication filter.
I am getting this error. What I am missing ?
Initialization of bean failed; nested exception is org.springframework.beans.ConversionNotSupportedException: Failed to convert property value of type ‘java.util.LinkedHashMap’ to required type ‘java.util.Map’ for property ‘filterChainMap’; nested exception is java.lang.IllegalStateException: Cannot convert value of type [com.asu.edu.base.vo.CaptchaFilterVO] to required type [javax.servlet.Filter] for property ‘filterChainMap[/**][3]’: no matching editors or conversion strategy found

My .java file

public class CaptchaFilterVO {
    @Autowired
    private ReCaptcha reCaptcha = null;

    public void doFilterInternal(HttpServletRequest req, HttpServletResponse res,
            FilterChain chain) throws IOException, ServletException {       
        String recaptcha_response = req.getParameter("recaptcha_response_field");
        String recaptcha_challenge = req.getParameter("recaptcha_challenge_field");
        String remoteAddress = req.getRemoteAddr();
        ReCaptchaResponse reCaptchaResponse = this.reCaptcha.checkAnswer(
                remoteAddress, recaptcha_challenge, recaptcha_response);
        if (!reCaptchaResponse.isValid()) {

            System.out.println("Captcha worong. Please try again.");        

        } 
        else 
        {
            System.out.println("Captcha correct. No need to try again.");
        }
        chain.doFilter(req, res);
    }
}

springsecurity.xml

     <http auto-config="true">
        <!-- intercept-url pattern="/welcome*" access="ROLE_DEPARTMENT_MGR,ROLE_REGULAR_EMP,ROLE_GUEST_USR,ROLE_CORPORATE_MGR" />
        <intercept-url pattern="/admin*" access="ROLE_ADMIN" /-->
        <intercept-url pattern="/login" filters="none" />
        <intercept-url pattern="/resources*" filters="none" />
        <intercept-url pattern="/register" filters="none" />
        <intercept-url pattern="/logout" filters="none" />
        <intercept-url pattern="/loginfailed" filters="none" />
        <intercept-url pattern="/admin*" access="ROLE_ADMIN" />
        <intercept-url pattern="/Dashboard*" access="ROLE_DEPARTMENT_MGR,ROLE_REGULAR_EMP,ROLE_CORPORATE_MGR" />
        <intercept-url pattern="/*" access="IS_AUTHENTICATED_FULLY"/>
        <form-login login-page="/login" default-target-url="/"
            authentication-failure-url="/loginfailed"   />
        <logout logout-success-url="/logout" />
        <custom-filter ref="captchaVerifierFilter" after="FORM_LOGIN_FILTER"/>

</http>     
 <beans:bean id="captchaVerifierFilter" class="com.asu.edu.base.vo.CaptchaFilterVO"/>
 <beans:bean id="springSecurityFilterChain" class="org.springframework.web.filter.DelegatingFilterProxy"/>
<beans:bean id="myfilterChainProxy" class="org.springframework.security.web.FilterChainProxy">
    <filter-chain-map path-type="ant">     
         <filter-chain pattern="/*" filters="springSecurityFilterChain,captchaVerifierFilter"/>
    </filter-chain-map>
 </beans:bean>

EDIT: public class CaptchaFilterVO extends OncePerRequestFilter implements javax.servlet.Filter
Now I have extended OncePerRequestFilter class but now I am facing a crash. Any help please.
org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [org.springframework.http.HttpRequest]: Specified class is an interface
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:894)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778)
javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:368)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:109)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)

Answer 1

Name of your method (doFilterInternal) suggests that you wanted to extend org.springframework.web.filter.OncePerRequestFilter.

Add:

extends OncePerRequestFilter

after the name of your class.

OncePerRequestFilter implements javax.servlet.Filter.

and…

Filter base class that guarantees to be just executed once per request,
on any servlet container. It provides a doFilterInternal
method with HttpServletRequest and HttpServletResponse arguments.