Chapter 1. Introduction

JBoss Transaction Service does not provide a security layer. The objects stored in the JBoss Transactions Object Store are typically owned by the user running the application that created them. The Object Store and Object Manager facilities do not enforce ownership of objects. Ownership of objects is not checked or enforced by the Transaction Manager.

Persistent objects created in the Object Store are never deleted unless the StateManager.destroy method is invoked on an object, or an application explicitly deletes them. This means that the Object Store gradually accumulates garbage, especially during application development and testing phases. JBoss Transaction Service provides no automated garbage collection facility. This lack of garbage collection can create dangling references. Here is an example of a dangling reference. A persistent object called ObjectA stores a Uid for ObjectB, which is also a persistent object, in its passive representation on disk. An application can delete ObjectB even though ObjectA still contains a reference to it. When ObjectA is next activated and attempts to access ObjectB, a run-time error occurs.

JBoss Transaction Service includes no version control of objects or database reconfiguration in the event of class structure changes. If you change the definition of a class of persistent objects, you must ensure that existing instances of the object in the Object Store are converted to the new representation. The JBoss Transactions Service software cannot detect or correct references to old object state by new operation versions or vice versa.

Object store management is critically important to the transaction service.