一个Java源文件只能有一个public class

文件名与公有类类名一致

源文件中可以有多个类, 但是不能都是公有的

如果没有公有类, 文件名与某个类类名一致-A Java source file can have only one public class file name and class name of the public class in the same source file can have more than one class, but can not are public if there is no public class, the file name with the same class name of a class