EJB programming model: http://www-900.ibm.com/developerWorks/cn/java/what-are-ejbs/part2/index.shtml
Abstract, inheritance: http://www.jdon.com/jive/Article.jsp?forum=16&thread=15603
For the doubts of transactions managed by the YBOSS HTTP: //www.jdon.com/jive/thread.jsp?forum=16&thread=16072
Http://www.goway.cn/baojian Download Resources