很抱歉打扰你们，谢谢您的帮助.
我找到了问题的答案，并且与Maven无关.对于1.4版以上的Java版本，您只能从命名包中导入默认包中的类，我使用的是1.7版.
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4989710

Sorry to bother you guys and thanks for your help.
I found the answer to my question and it has nothing to do with maven. You just cannot import classes in default package from named package for java versions above 1.4, I was using 1.7 version for compilation.
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4989710