demo_28\.classpath
.......\.project
.......\.settings\org.eclipse.jdt.core.prefs
.......\bin\demo_01\Demo1.class
.......\...\......2\Demo.class
.......\...\.......\Demo2.class
.......\src\demo_01\Demo1.java
.......\...\......2\Demo.java
.......\...\.......\Demo2.java
.......\在一个包中调用另一个包中某个类的方法
.......\bin\demo_01
.......\...\demo_02
.......\src\demo_01
.......\...\demo_02
.......\.settings
.......\bin
.......\src
demo_28