添加依赖

<!--JWT依赖-->
<dependency>
    <groupId>io.jsonwebtoken</groupId>
    <artifactId>jjwt</artifactId>
    <version>0.9.1</version>
</dependency>

解析的代码

@GetMapping("/getCurrentUser")
public Object getCurrentUser(Authentication authentication,
                             HttpServletRequest request) {
    String header = request.getHeader("Authorization");
    String token = null;
    if(header!=null){
        token = header.substring(header.indexOf("bearer") + 7);
    }else {
        token = request.getParameter("access_token");
    }
    return Jwts.parser()
        .setSigningKey("123123".getBytes(StandardCharsets.UTF_8))
        .parseClaimsJws(token)
        .getBody();
}

测试