动物园
......\.classpath
......\.project
......\.settings
......\.........\org.eclipse.jdt.core.prefs
......\bin
......\...\animals
......\...\.......\Animal.class
......\...\.......\Cat.class
......\...\.......\Duck.class
......\...\.......\Legs.class
......\...\.......\Test.class
......\src
......\...\animals
......\...\.......\Animal.java
......\...\.......\Cat.java
......\...\.......\Duck.java
......\...\.......\Legs.java
......\...\.......\Test.java