Efficient Dynamic Multikeys in Enterprise JavaBeans

The J2EE platform allows the rapid development of a large class of complex and robust server-side applications. However, some J2EE constraints pose serious challenges to the development of J2EE applications that interact with legacy systems outside the originally targeted J2EE domain. One such constraint is the static nature of identities of entity Enterprise JavaBeans (EJBs). We present a case study that motivates the introduction of dynamic sets of identities of entity EJBs, which we call dynamic multikeys, and describe five different ways of implementing dynamic multikeys based on static EJB identities. We compare the characteristics of our dynamic multikey solutions and demonstrate through performance tests that one of them is superior from a performance point of view. However, each one of the slower solutions offers distinct advantages that may make it attractive to some developers and for applications where the performance of dynamic multikeys is not a critical factor.