7.4. Managed and Non-Managed Environments
The terms managed and non-managed have been used at various points in the book to differentiate between traditional two-tier Java applications and multi-tier Java applications.
A two-tier Java application explicitly connects to the underlying datastore (which constitutes the second tier) and begins and ends its own local transactions. A two-tier application typically starts, does something at the bequest of a user and ends.
A multi-tier Java application requests connections from a connection manager and may delegate transaction control to an external coordinator. This coordinator begins and ends transactions implicitly, potentially coordinating multiple different data sources into a single distributed ...