为了使生成的图形用户界面与操作系统无关，Java语言提供了布局管理器来管理组件在容器中的布局，而不使用直接设置组件的位置和大小的方式。-In order to make the generated graphical user interface (GUI) has nothing to do with the operating system, the Java language provides the layout manager to manage the components in the layout in the container, instead of using the method of setting the size and location of the component directly.