loadUserByUsername获取空用户名

我正在使用spring boot 2.1.9.RELEASE spring-boot-starter-security 2.1.8.RELEASE但是当我使用loadByUsername函数时，我得到一个空用户名

我的登录页面

      this.$axios({
        method: 'post',
        url: "api/login",
        data:this.loginForm,
        headers:{'Content-Type': 'application/x-www-form-urlencoded'}}
      )

我的安全性配置

@Configuration public class WebSecurityConfig extends WebSecurityConfigurerAdapter { @Autowired UserServiceImpl userServiceImpl;

@Override
protected void configure(AuthenticationManagerBuilder auth) throws Exception{
    auth.userDetailsService(userServiceImpl).passwordEncoder(new BCryptPasswordEncoder() {
        @Override
        public String encode(CharSequence charSequence) {
            return DigestUtils.md5DigestAsHex(charSequence.toString().getBytes());
        }
        @Override
        public boolean matches(CharSequence charSequence, String s) {
            return s.equals(DigestUtils.md5DigestAsHex(charSequence.toString().getBytes()));
        }
    });
}

@Override
protected void configure(HttpSecurity http) throws Exception{
    http.authorizeRequests()
            .antMatchers("/admin/category/all").authenticated()
            .antMatchers("/admin/**","/reg").hasRole("超级管理员")
            .anyRequest().anonymous()
            .and().formLogin().loginPage("/api/login")
            .usernameParameter("username")
            .passwordParameter("password")
            .permitAll()
            .and().logout().permitAll().and().csrf().disable().exceptionHandling();

}

@Override
public void configure(WebSecurity web) throws Exception {
    web.ignoring().antMatchers("/blogimg/**","/index.html","/static/**");
}

} 我的loadUserByUserName方法

@Override public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException { Optional user = Optional.ofNullable(userMapper.loadUserByUsername(username)); User user1 = user.orElse(new User()); List roles = rolesMapper.getRolesByUid(user1.getId()); user1.setRoles(roles); return user1; } 方法loadUserByUsername（）始终为空用户；

如果我在url.loadUserByUserName（）中加入参数，则可以获取用户名；