<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-api</artifactId>
<version>0.11.5</version>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-impl</artifactId>
<version>0.11.5</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-jackson</artifactId>
<version>0.11.5</version>
<scope>runtime</scope>
</dependency>

import io.jsonwebtoken.*;
import io.jsonwebtoken.security.Keys;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import javax.crypto.SecretKey;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
@Component
public class JwtUtils {
@Value("${jwt.secret}")
private String secret;
@Value("${jwt.expiration}")
private long expiration;
// 生成token
public String generateToken(String username) {
Map<String, Object> claims = new HashMap<>();
SecretKey key = Keys.hmacShaKeyFor(secret.getBytes());
return Jwts.builder()
.setClaims(claims)
.setSubject(username)
.setIssuedAt(new Date())
.setExpiration(new Date(System.currentTimeMillis() + expiration * 1000))
.signWith(key, SignatureAlgorithm.HS256)
.compact();
}
// 解析token獲取用戶名
public String getUsernameFromToken(String token) {
SecretKey key = Keys.hmacShaKeyFor(secret.getBytes());
return Jwts.parserBuilder()
.setSigningKey(key)
.build()
.parseClaimsJws(token)
.getBody()
.getSubject();
}
// 驗證token是否有效
public boolean validateToken(String token) {
try {
SecretKey key = Keys.hmacShaKeyFor(secret.getBytes());
Jwts.parserBuilder().setSigningKey(key).build().parseClaimsJws(token);
return true;
} catch (Exception e) {
return false;
}
}
}

@Component
public class JwtAuthenticationFilter extends OncePerRequestFilter {
@Autowired
private JwtUtils jwtUtils;
@Override
protected void doFilterInternal(HttpServletRequest request,
HttpServletResponse response,
FilterChain chain)
throws ServletException, IOException {
String token = request.getHeader("Authorization");
// 如果請求頭中沒有token，直接放行
if (StringUtils.isEmpty(token)) {
chain.doFilter(request, response);
return;
}
// 驗證token有效性
if (!jwtUtils.validateToken(token)) {
response.setStatus(HttpStatus.UNAUTHORIZED.value());
response.getWriter().write("無效的Token");
return;
}
// 獲取用戶名并設(shè)置到SecurityContext中
String username = jwtUtils.getUsernameFromToken(token);
UsernamePasswordAuthenticationToken authentication =
new UsernamePasswordAuthenticationToken(username, null, new ArrayList<>());
SecurityContextHolder.getContext().setAuthentication(authentication);
chain.doFilter(request, response);
}
}

@Configuration
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
@Autowired
private JwtAuthenticationFilter jwtAuthenticationFilter;
@Override
protected void configure(HttpSecurity http) throws Exception {
http.csrf().disable()
.authorizeRequests()
.antMatchers("/api/auth/**").permitAll()
.anyRequest().authenticated()
.and()
.addFilterBefore(jwtAuthenticationFilter, UsernamePasswordAuthenticationFilter.class);
}
}