spring security token鉴权时返回403，我想返回自定义异常

可以通过实现 Spring Security 中的 AccessDeniedHandler 接口来自定义处理访问被拒绝的情况。具体实现可以参考以下代码：

@Component
public class CustomAccessDeniedHandler implements AccessDeniedHandler {

    @Override
    public void handle(HttpServletRequest request, HttpServletResponse response, AccessDeniedException accessDeniedException) throws IOException, ServletException {
        response.setStatus(HttpServletResponse.SC_FORBIDDEN);
        response.setContentType("application/json;charset=utf-8");
        PrintWriter out = response.getWriter();
        out.write("{\"status\":\"error\",\"msg\":\"权限不足，请联系管理员!\"}");
        out.flush();
        out.close();
    }
}

然后在 Spring Security 的配置类中将该处理器添加进去：

@Configuration
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {

    @Autowired
    private CustomAccessDeniedHandler customAccessDeniedHandler;

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.authorizeRequests()
                .anyRequest().authenticated()
                .and()
                .exceptionHandling()
                .accessDeniedHandler(customAccessDeniedHandler);
    }
}

这样，当访问被拒绝时，就会返回自定义的异常信息了。