Local transaction containment (LTC)
A local transaction containment (LTC) is used to define the appserver behavior in an unspecified transaction context.
Unspecified transaction context is defined in the Enterprise JavaBeans 2.0 (or later) specification; for example, at http://java.sun.com/products/ejb/2.0.html.
A LTC is a bounded unit-of-work scope, within which zero, one, or more resource manager local transactions (RMLTs) can be accessed. The LTC defines the boundary at which all RMLTs must be complete; any incomplete RMLTs are resolved, according to policy, by the container. An LTC is local to a bean instance; it is not shared across beans, even if those beans are managed by the same container. LTCs are started by the container before dispatching a method on a J2EE component (such as an enterprise bean or servlet) whenever the dispatch occurs in the absence of a global transaction context. LTCs are completed by the container depending on the application-configured LTC boundary; for example at the end of the method dispatch. There is no programmatic interface to the LTC support; rather LTCs are managed exclusively by the container and configured by the application deployer through transaction attributes in the application deployment descriptor. A local transaction containment cannot exist concurrently with a global transaction. If application component dispatch occurs in the absence of a global transaction, the container always establishes an LTC for J2EE components at J2EE 1.3 or later. The only exceptions to this are as follows:
- Where application component dispatch occurs without container interposition; for example, for a stateless session bean create or a servlet-initiated thread.
- J2EE 1.2 web components.
- J2EE 1.2 BMT enterprise beans.
A local transaction containment can be scoped to an ActivitySession context that lives longer than the enterprise bean method in which it is started, as described in ActivitySessions and transaction contexts.
Related concepts
ActivitySession and transaction contexts
Unshareable and shareable connections
Transaction support in WAS
Related tasks
Configure transactional deployment attributes
Related Reference
Local transaction containment considerations