多项选择题
A. A
B. The echo tag handler must define the setAttribute （String key， String value） method
C. The
D. The class implementing the echo tag handler must implement the javax.sevlet.jsp.tagext.IterationTag interface
E. The class implementing the echo tag handler must implement the javax.sevlet.jsp.tagext.DynamicAttributes interface
多项选择题 Whichthe twoarevalidandequivalent？（）
单项选择题 A developer is designing a web application which extensively uses EJBs and JMS. The developer finds that there is a lot of duplicated code to build the JNDI contexts to access the beans and queues. Further， because of the complexity， there are numerous errors in the code. Which J2EE design pattern provides a solution for this problem？（）
多项选择题 Whichthe twoarecharacteristicsoftheServiceLocatorpattern？（）