FactoryDemo\classes
...........\.......\city
...........\.......\....\BeiJing.class
...........\.......\....\HaiNan.class
...........\.......\....\ShangHai.class
...........\.......\provinceFactory
...........\.......\...............\FactoryDemo.class
...........\.......\...............\ProvinceFactory.class
...........\.......\provinceInterface
...........\.......\.................\Province.class
...........\.......\.................\ProvinceInterface.class
...........\FactoryDemo.jcp
...........\src
...........\...\BeiJing.java
...........\...\FactoryDemo.java
...........\...\HaiNan.java
...........\...\Province.java
...........\...\ProvinceFactory.java
...........\...\ShangHai.java