How to Inject Utility Class into Jakarta Filter through Spring IoC container

Question

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I wrote a utility class JwtUtils.java, annotated it as a component, and injected it into another class, CustomFilter.java, which is also annotated as a component. CustomFilter implements a Filter interface. After injecting I cannot access methods inside the util class. It's throwing NullPointerException.

Jakarta Filter is executing before the request controller for JWT Authentication.

JwtUtils class:

@Component
public class JwtUtils {

    @Value("${JWT_SECRET}")
    public String SECRET_KEY;

    public String getUsernameFromToken(String token) {

        Jws<Claims> claims = Jwts.parser()
                .setSigningKey(SECRET_KEY)
                .parseClaimsJws(token);

        Object claimsBody = claims.getBody();
        String jsonString = new Gson().toJson(claimsBody);
        JSONObject obj = new JSONObject(jsonString);
        return obj.getString("username");
    }

    public boolean validateToken(String token) {
        try {
            Jwts.parser()
                    .setSigningKey(SECRET_KEY)
                    .parseClaimsJws(token);
            return true;
        } catch (Exception e) {
            return false;
        }
    }

    public Authentication getAuthentication(String token) {
        Authentication auth = new Authentication();
        auth.setUsername(getUsernameFromToken(token));
        System.out.println(auth.toString());
        return auth;
    }
}

CustomFilter class:

@Component
public class CustomFilter implements Filter {
    @Autowired
    JwtUtils util;

    public CustomFilter() {
    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
            throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        String token = extractTokenFromHeader(request.getHeader("Authorization"));

        if (util.validateToken(token)) {
            request.setAttribute("username", util.getUsernameFromToken(token));
            filterChain.doFilter(request, response);
        } else {
            ErrorDetails errorDetails = new ErrorDetails(new Date(), "Access Unauthorized",
                    "Authorization Token is Missing/Invalid/Expired", 401);
            response.setStatus(401);
            response.setContentType("application/json");
            response.getWriter().write(convertObjectToJson(errorDetails));
        }

    }

    private String extractTokenFromHeader(String header) {
        if (StringUtils.hasText(header) && header.startsWith("Bearer ")) {
            return header.substring(7);
        }
        return null;
    }

    public String convertObjectToJson(Object object) throws JsonProcessingException {
        if (object == null) {
            return null;
        }
        ObjectMapper mapper = new ObjectMapper();
        return mapper.writeValueAsString(object);
    }

}

The Exception:

java.lang.NullPointerException: Cannot invoke "com.fp.common.util.JwtUtils.validateToken(String)" because "this.util" is null at com.fp.common.validation.CustomFilter.doFilter(CustomFilter.java:34) 

I want to access util methods from the Jakarta custom filter class through the spring IoC container. Please leave a suggestion if this issue is in your scope