JwtUtils.java

package me.schawe.multijsnake.usermanagement;

import io.jsonwebtoken.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.security.core.Authentication;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;

import javax.servlet.http.HttpServletRequest;
import java.util.Date;

@Component
public class JwtUtils {
    private static final Logger logger = LoggerFactory.getLogger(AuthEntryPointJwt.class);

    @Value("${me.schawe.jwtSecret}")
    private String jwtSecret;

    @Value("${me.schawe.jwtDurationMS}")
    private int jwtExpirationMs;

    public String generateJwtToken(Authentication authentication) {

        UserDetailsImpl userPrincipal = (UserDetailsImpl) authentication.getPrincipal();

        return Jwts.builder().setSubject((userPrincipal.getUsername())).setIssuedAt(new Date())
                .setExpiration(new Date((new Date()).getTime() + jwtExpirationMs)).signWith(SignatureAlgorithm.HS512, jwtSecret)
                .compact();
    }

    public String getUserNameFromJwtToken(String token) {
        return Jwts.parser().setSigningKey(jwtSecret).parseClaimsJws(token).getBody().getSubject();
    }

    public boolean validateJwtToken(String authToken) {
        try {
            Jwts.parser().setSigningKey(jwtSecret).parseClaimsJws(authToken);
            return true;
        } catch (SignatureException e) {
            logger.error("Invalid JWT signature: {}", e.getMessage());
        } catch (MalformedJwtException e) {
            logger.error("Invalid JWT token: {}", e.getMessage());
        } catch (ExpiredJwtException e) {
            logger.error("JWT token is expired: {}", e.getMessage());
        } catch (UnsupportedJwtException e) {
            logger.error("JWT token is unsupported: {}", e.getMessage());
        } catch (IllegalArgumentException e) {
            logger.error("JWT claims string is empty: {}", e.getMessage());
        }

        return false;
    }

    public static String parseJwt(HttpServletRequest request) {
        String headerAuth = request.getHeader("Authorization");

        if (StringUtils.hasText(headerAuth) && headerAuth.startsWith("Bearer ")) {
            return headerAuth.substring(7);
        }

        return null;
    }
}