If the nested class is a static class, a box showing a preview of the refactoring displays right away.

如果这个嵌套类是一个静态类，那么就会立即出现一个框，显示这个重构的预览。

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If it is not a static class, you first need to declare the name of the field that will hold the reference to the parent class of the nested class before you get to the preview box.

如果它不是一个静态类，那么需要首先声明保存有对此嵌套类的父类的引用的那个字段的名称，之后才能看到这个预览框。

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