<!--引入jwt相關(guān)包來(lái)生成token-->
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt-api</artifactId>
            <version>0.11.2</version>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt-impl</artifactId>
            <version>0.11.2</version>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt-jackson</artifactId>
            <version>0.11.2</version>
            <scope>runtime</scope>
        </dependency>

dependencies {  
    implementation 'io.jsonwebtoken:jjwt-api:0.11.2' 
    runtimeOnly 'io.jsonwebtoken:jjwt-impl:0.11.2'   
    runtimeOnly 'io.jsonwebtoken:jjwt-jackson:0.11.2' 
}

import com.certificateManage.common.R;
import com.certificateManage.controller.exception.TokenException;
import io.jsonwebtoken.*;
import io.jsonwebtoken.security.Keys;
import io.jsonwebtoken.security.SignatureException;

import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.util.Date;

//用于生成token的類(lèi)
public class JwtTokenUtil {

    private static final String SECRET_KEY = "abcdefgabcdefghijklmnopqrstuvwxyz"; // 密鑰
    private static final SignatureAlgorithm signatureAlgorithm = SignatureAlgorithm.HS256;//加密方式
    //ttMillis是token持續(xù)時(shí)間
    public static String createToken(String id, long ttlMillis) {
        // 簽名密鑰
        byte[] secretKeyBytes = SECRET_KEY.getBytes(StandardCharsets.UTF_8);
        SecretKeySpec secretKeySpec = new SecretKeySpec(secretKeyBytes, signatureAlgorithm.getJcaName());

        // 設(shè)置JWT的簽發(fā)時(shí)間和過(guò)期時(shí)間
        Date now = new Date();
        Date expiration = new Date(now.getTime() + ttlMillis);
        // 使用指定的密鑰和算法生成JWT
        return Jwts.builder()
                .setSubject(id)//設(shè)置id
                .setIssuedAt(now) // 設(shè)置簽發(fā)時(shí)間
                .setExpiration(expiration) // 設(shè)置過(guò)期時(shí)間
                .signWith(secretKeySpec,signatureAlgorithm) // 設(shè)置簽名密鑰和簽名算法
                .compact(); // 生成JWT字符串
    }


    //驗(yàn)證token如果正確返回用戶id
    public static R checkToken(String token){
        try {
            // 解析token  
            Claims claims = Jwts.parser()
                    .setSigningKey(Keys.hmacShaKeyFor(SECRET_KEY.getBytes(StandardCharsets.UTF_8))) // 設(shè)置密鑰  
                    .parseClaimsJws(token) // 解析token  
                    .getBody(); // 獲取負(fù)載  

            // 驗(yàn)證負(fù)載中的信息  
            String subject = claims.getSubject(); // 獲取用戶ID或其他信息  
            Date expiration = claims.getExpiration(); // 獲取過(guò)期時(shí)間  
            System.out.println(expiration.toString());

            // 驗(yàn)證token是否過(guò)期  
            if (expiration.before(new Date())) {
                throw new TokenException("token失效");
            }
            return R.success(subject);

        } catch (ExpiredJwtException e) {
            // 當(dāng)token過(guò)期時(shí)，會(huì)捕獲到ExpiredJwtException異常  
            return R.error("Token已過(guò)期");
        } catch (UnsupportedJwtException e) {
            // 當(dāng)token不受支持時(shí)，會(huì)捕獲到UnsupportedJwtException異常  
            return R.error("Token不受支持");
        } catch (MalformedJwtException e) {
            // 當(dāng)token格式錯(cuò)誤時(shí)，會(huì)捕獲到MalformedJwtException異常  
            return R.error("Token格式錯(cuò)誤");
        } catch (SignatureException e) {
            // 當(dāng)token簽名錯(cuò)誤時(shí)，會(huì)捕獲到SignatureException異常  
            return R.error("Token簽名錯(cuò)誤");
        } catch (IllegalArgumentException e) {
            // 當(dāng)token為空或非法時(shí)，會(huì)捕獲到IllegalArgumentException異常  
            return R.error("Token為空或非法");
        } catch (TokenException e) {
            // 處理TokenException  
            return R.error("Token驗(yàn)證失敗: " + e.getMessage());
        } catch (Exception e) {
            // 處理其他異常  
            return R.error("發(fā)生未知錯(cuò)誤: " + e.getMessage());
        }
    }
}
// TokenException類(lèi)，用于處理與Token相關(guān)的異常  
public class TokenException extends Exception {  
    public TokenException(String message) {  
        super(message);  
    }  
}  
}

//統(tǒng)一返回為結(jié)果集R   1為成功,0為失敗
public class R<T>  {

    private Integer code; //編碼：1成功，0和其它數(shù)字為失敗
    private String msg; //錯(cuò)誤信息
    private T data; //數(shù)據(jù)

    //靜態(tài)方法返回成功時(shí)候,R的屬性
    public static <T> R<T> success(T object) {
        R<T> r = new R<>();
        r.data = object;
        r.code = 1;
        return r;
    }

    //靜態(tài)方法返回失敗時(shí)傳入消息
    public static <T> R error(String msg) {
        R r = new R();
        r.msg = msg;
        r.code = 0;
        return r;
    }
    // getter和setter方法省略...  
}

 String token=JwtTokenUtil.createToken(String.valueOf(user.getId()),3600000L);//生成token返回前端
 return R.success(token);

public class BaseContext {
    // 使用ThreadLocal來(lái)存儲(chǔ)用戶ID
    private static final ThreadLocal<String> userIdThreadLocal = new ThreadLocal<>();

    // 設(shè)置用戶ID
    public static void setUserId(String userId) {
        userIdThreadLocal.set(userId);
    }

    // 獲取用戶ID
    public static String getUserId() {
        return userIdThreadLocal.get();
    }

    // 清除用戶ID（通常在請(qǐng)求處理完畢后調(diào)用）
    public static void clearUserId() {
        userIdThreadLocal.remove();
    }
}

import com.certificateManage.common.BaseContext;
import com.certificateManage.common.R;
import com.certificateManage.util.tokenUtil.JwtTokenUtil;
import org.springframework.lang.Nullable;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@Component
public class JwtInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        // 從請(qǐng)求頭中獲取JWT
        String token = request.getHeader("Authorization");
        if ("OPTIONS".equalsIgnoreCase(request.getMethod())){
            System.out.println("OPTIONS請(qǐng)求，放行");
            return true;
        }
        if (token == null || !token.startsWith("Bearer ")) {
            // 如果沒(méi)有JWT或者格式不正確，返回錯(cuò)誤
            response.sendError(HttpServletResponse.SC_UNAUTHORIZED, "token令牌不存在或請(qǐng)求頭格式錯(cuò)誤");
            return false;
        }
        // 去除"Bearer "前綴，獲取真正的JWT
        token = token.substring(7);

        try {
            // 驗(yàn)證JWT
            R r=JwtTokenUtil.checkToken(token);
            // JWT驗(yàn)證成功，繼續(xù)處理請(qǐng)求
            if (r.getCode()==1) {
                // 將用戶ID存儲(chǔ)在ThreadLocal中
                BaseContext.setUserId(String.valueOf(r.getData()));
                return true;
            }else {
                // JWT驗(yàn)證失敗，返回錯(cuò)誤
                response.sendError(HttpServletResponse.SC_UNAUTHORIZED, "Token驗(yàn)證失敗");
                return false;
            }
        } catch (Exception e) {
            // JWT驗(yàn)證失敗，返回錯(cuò)誤
            response.sendError(HttpServletResponse.SC_UNAUTHORIZED, "Token驗(yàn)證失敗");
            return false;
        }
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, @Nullable ModelAndView modelAndView) throws Exception {
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        // 在請(qǐng)求處理完畢后清除用戶ID
        BaseContext.clearUserId();
    }
}