No enclosing instance of type Face is accessible. Must qualify the allocation with an enclosing inst

刚才在练习内部类的时候遇到了这个报错：

No enclosing instance of type Face is accessible. Must qualify the allocation with an enclosing instance of type Face (e.g. x.new A() where x is an instance of Face).

意思大概是没有可访问的内部类的实例

我这里忘了放代码，只记得是往内部类前面加个static成为静态就好了。