实现打开文件夹的功能，用JAVA语言，虽然简单，但对初学者很有帮助-Open folder realize the function, using JAVA language, although simple, but very helpful for beginners

Java语言编写的文件操作方法，打开并且返回文件的输入流对象。-File operation methods write with Java, open and returns file input stream object。