Enterprise JavaBeans规范要求每一个bean提供者遵循一组编程指南,旨在确保bean将便携式和行为始终在任何EJB容器。在这种情况下,EJB产品违反下列指南:“企业bean必须不使用线程同步原语同步执行的多个实例。”The specification justifies this requirement in the following way: "This rule is required to ensure consistent runtime semantics because while some EJB containers may use a single JVM to execute all enterprise bean's instances, others may distribute the instances across multiple JVMs."