Spring Security custom authentication filter using Java Config

I’ve resolved my issue by performing a check on the authentication status in the filter before involking the authentication provider….

Config

.and()
    .addFilterBefore(tokenFilter, UsernamePasswordAuthenticationFilter.class)
    .authenticationProvider(tokenAuthenticationProvider)
    .exceptionHandling().authenticationEntryPoint(tokenEntryPoint)

Filter

@Override
public void doFilter(final ServletRequest request, final ServletResponse response, final FilterChain chain)
        throws IOException, ServletException {

    logger.debug(this + "received authentication request from " + request.getRemoteHost() + " to " + request.getLocalName());

    if (request instanceof HttpServletRequest) {
        if (isAuthenticationRequired()) {
            // extract token from header
            OEWebToken token = extractToken(request);

            // dump token into security context (for authentication-provider to pick up)
            SecurityContextHolder.getContext().setAuthentication(token);
        } else {
            logger.debug("session already contained valid Authentication - not checking again");
        }
    }

    chain.doFilter(request, response);
}

    private boolean isAuthenticationRequired() {
    // apparently filters have to check this themselves.  So make sure they have a proper AuthenticatedAccount in their session.
    Authentication existingAuth = SecurityContextHolder.getContext().getAuthentication();
    if ((existingAuth == null) || !existingAuth.isAuthenticated()) {
        return true;
    }

    if (!(existingAuth instanceof AuthenticatedAccount)) {
        return true;
    }

    // current session already authenticated
    return false;
}