File list (Check if you may need any files):
ObserverTest\.classpath
............\.project
............\.settings\org.eclipse.jdt.core.prefs
............\bin\com\example\observer\BeObserved.class
............\...\...\.......\........\ListenerTest.class
............\...\...\.......\........\MainTest.class
............\...\...\.......\........\ObserverClass.class
............\...\...\.......\........\ObserverManager.class
............\src\com\example\observer\BeObserved.java
............\...\...\.......\........\ListenerTest.java
............\...\...\.......\........\MainTest.java
............\...\...\.......\........\ObserverClass.java
............\...\...\.......\........\ObserverManager.java
............\bin\com\example\observer
............\src\com\example\observer
............\bin\com\example
............\src\com\example
............\bin\com
............\src\com
............\.settings
............\bin
............\src
ObserverTest