JwtTokenUtil

package me.zhengjie.core.utils;

import io.jsonwebtoken.*;
import io.jsonwebtoken.impl.DefaultClock;
import me.zhengjie.common.exception.BadRequestException;
import me.zhengjie.core.security.JwtUser;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.HttpStatus;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import javax.servlet.http.HttpServletRequest;
import java.io.Serializable;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import java.util.function.Function;

@Component
public class JwtTokenUtil implements Serializable {

    private static final long serialVersionUID = -3301605591108950415L;
    private Clock clock = DefaultClock.INSTANCE;

    @Value("${jwt.secret}")
    private String secret;

    @Value("${jwt.expiration}")
    private Long expiration;

    @Value("${jwt.header}")
    private String tokenHeader;

    public String getUsernameFromToken(String token) {
        return getClaimFromToken(token, Claims::getSubject);
    }

    public Date getIssuedAtDateFromToken(String token) {
        return getClaimFromToken(token, Claims::getIssuedAt);
    }

    public Date getExpirationDateFromToken(String token) {
        return getClaimFromToken(token, Claims::getExpiration);
    }

    public  T getClaimFromToken(String token, Function claimsResolver) {
        final Claims claims = getAllClaimsFromToken(token);
        return claimsResolver.apply(claims);
    }

    private Claims getAllClaimsFromToken(String token) {
        return Jwts.parser()
                .setSigningKey(secret)
                .parseClaimsJws(token)
                .getBody();
    }

    private Boolean isTokenExpired(String token) {
        final Date expiration = getExpirationDateFromToken(token);
        return expiration.before(clock.now());
    }

    private Boolean isCreatedBeforeLastPasswordReset(Date created, Date lastPasswordReset) {
        return (lastPasswordReset != null && created.before(lastPasswordReset));
    }

    private Boolean ignoreTokenExpiration(String token) {
        // here you specify tokens, for that the expiration is ignored
        return false;
    }

    public String generateToken(UserDetails userDetails) {
        Map claims = new HashMap<>();
        return doGenerateToken(claims, userDetails.getUsername());
    }

    private String doGenerateToken(Map claims, String subject) {
        final Date createdDate = clock.now();
        final Date expirationDate = calculateExpirationDate(createdDate);

        return Jwts.builder()
                .setClaims(claims)
                .setSubject(subject)
                .setIssuedAt(createdDate)
                .setExpiration(expirationDate)
                .signWith(SignatureAlgorithm.HS512, secret)
                .compact();
    }

    public Boolean canTokenBeRefreshed(String token, Date lastPasswordReset) {
        final Date created = getIssuedAtDateFromToken(token);
        return !isCreatedBeforeLastPasswordReset(created, lastPasswordReset)
                && (!isTokenExpired(token) || ignoreTokenExpiration(token));
    }

    public String refreshToken(String token) {
        final Date createdDate = clock.now();
        final Date expirationDate = calculateExpirationDate(createdDate);

        final Claims claims = getAllClaimsFromToken(token);
        claims.setIssuedAt(createdDate);
        claims.setExpiration(expirationDate);

        return Jwts.builder()
                .setClaims(claims)
                .signWith(SignatureAlgorithm.HS512, secret)
                .compact();
    }

    public Boolean validateToken(String token, UserDetails userDetails) {
        JwtUser user = (JwtUser) userDetails;
        final String username = getUsernameFromToken(token);
        final Date created = getIssuedAtDateFromToken(token);
        //final Date expiration = getExpirationDateFromToken(token);
        return (
                username.equals(user.getUsername())
                        && !isTokenExpired(token)
                        && !isCreatedBeforeLastPasswordReset(created, user.getLastPasswordResetDate())
        );
    }
    public  String getUserName(HttpServletRequest request){

        String authToken = request.getHeader(tokenHeader);

        if(StringUtils.isEmpty(authToken)||authToken.length()<7){
            throw new BadRequestException(HttpStatus.FORBIDDEN,"Token令牌无效");
        }

        final String token = authToken.substring(7);
        String username = null;
        try {
            username = getUsernameFromToken(token);
        } catch (ExpiredJwtException e){
            throw new BadRequestException(HttpStatus.UNAUTHORIZED,"Token令牌已过期");
        }

        return username;
    }

    private Date calculateExpirationDate(Date createdDate) {
        return new Date(createdDate.getTime() + expiration);
    }
}

 

转载于:https://www.cnblogs.com/tonggc1668/p/11216939.html