对于@Primary注解的使用

当一个接口存在多个实现的时候会报org.springframework.beans.factory.NoUniqueBeanDefinitionException类似的异常信息,项目中碰到引用别人事先写好的框架,但是对于其中个别实现并不是很需要,因此可以通过使用@Primary注解进行处理

比如处理登录失败时

@Component
public class OtherAuthenticationFailureHandler extends SimpleUrlAuthenticationFailureHandler {
    public HcAuthenticationFailureHandler() {
    }

    public void onAuthenticationFailure(HttpServletRequest request, HttpServletResponse response, AuthenticationException exception) {
        if (exception instanceof SessionAuthenticationException) {
            ResponseUtil.out(response, HttpStatus.UNAUTHORIZED, AjaxMessage.error("该账户登录数量已达上限，请先下线别处的登录！"));
        } else {
            ResponseUtil.out(response, HttpStatus.UNAUTHORIZED, AjaxMessage.error(exception.getMessage()));
        }

    }
}


我需要对返回的异常再进一步处理，@Primary指优先使用本处理器

@Primary
@Component
public class AuthenticationFailureHandler extends HcAuthenticationFailureHandler {

    @Override
    public void onAuthenticationFailure(HttpServletRequest request, HttpServletResponse response, AuthenticationException exception) {
        if (exception instanceof SessionAuthenticationException) {
            ResponseUtil.out(response, HttpStatus.UNAUTHORIZED, AjaxMessage.error("该账户登录数量已达上限，请先下线别处的登录！"));
        } else {
            if (exception instanceof ValidateLoginException && exception.getMessage().equals("账户不存在")) {
                ResponseUtil.out(response, HttpStatus.UNAUTHORIZED, AjaxMessage.error("用户名或密码错误"));
            } else {
                ResponseUtil.out(response, HttpStatus.UNAUTHORIZED, AjaxMessage.error(exception.getMessage()));
            }
        }

    }
}