NHibernateUnitOfWork¶

NHibernateUnitOfWork owns the transaction boundary for a single NHibernate session and hands out Repository<TEntity> instances bound to that session. It is returned by IUnitOfWorkFactory.GetUnitOfWork and is the type application code interacts with directly to begin/commit/roll back work and obtain repositories. It is classified as a framework-inherited type because it implements the external IUnitOfWork contract, which could not be located in this repository (see Dependencies).

Purpose¶

Enforces the unit-of-work transaction lifecycle: Begin() starts a transaction (rejecting a second Begin() while one is active — BR-001); Commit() requires a prior Begin() (BR-002); Rollback() unconditionally disposes the session after rolling back any active transaction.
Provides GetRepository<TEntity>(), which always constructs a new Repository<TEntity> bound to this unit of work's Session/SessionHelper, per BR-005 — every repository obtained from the same unit of work shares the same transaction.
Exposes Session (the underlying ISessionStrategy) and SessionHelper (the engine-specific date/ID helper) for repository construction.

Context¶

Namespace: SAIF.Data.NHibernate.UnitOfWork
Assembly/package: SAIF.Framework.Data.NHibernate

Public members¶

Member	Signature	Purpose
Session	`public ISessionStrategy Session { get; }`	The session strategy (stateful or stateless) this unit of work wraps; shared by every repository obtained from `GetRepository<TEntity>()`.
SessionHelper	`public ISessionHelper SessionHelper { get; }`	The engine-specific session helper (`OracleSessionHelper`/`SqlServerSessionHelper`) used for `SystemDate` and related engine-specific behavior.
Begin	`public void Begin()`	Checks `IsTransactionInProgress()` (transaction `IsActive`, `WasCommitted`, or `WasRolledBack`); throws `InvalidOperationException("There is a transaction already in progress.")` if so. Otherwise calls `Session.Clear()` then `Session.BeginTransaction(IsolationLevel.ReadCommitted)`. See BR-001.
Commit	`public void Commit()`	Gets the current `ITransaction`; throws `InvalidOperationException("You must call Begin() on the unit of work before you can commit.")` if it is not active. Otherwise calls `transaction.Commit()` then `Session.Clear()`. See BR-002.
Rollback	`public void Rollback()`	If the transaction `IsActive`, calls `transaction.Rollback()`; then always calls `Session.Dispose()` regardless of whether a transaction was active.
GetRepository<TEntity>	`public Repository<TEntity> GetRepository<TEntity>() where TEntity : IDataEntity`	Constructs and returns a new `Repository<TEntity>` bound to `this` unit of work's session — every call returns a fresh repository instance sharing the same underlying session/transaction.
Dispose	`public void Dispose()`	Standard dispose pattern: if not already disposed and `Session` is not null, calls `Session.Dispose()`.

Behavioral notes¶

Rollback() disposes the session even when no transaction was active — callers should treat any Rollback() call as terminal for the unit of work.
All repositories obtained from a given NHibernateUnitOfWork instance (via GetRepository<TEntity>()) participate in the same transaction — the NHibernate-stack analogue of a BOF-style transaction-wrapping pattern per the nhibernate-data-access skill.*

Constraints and usage notes¶

A single NHibernateUnitOfWork instance must not have Begin() called twice without an intervening Commit()/Rollback() (BR-001).
Commit() must always be preceded by Begin() on the same instance (BR-002).

Note: Statements marked with * were inferred from code structure, naming conventions, or contextual evidence where direct confirmation was not available in source artifacts.

Sources¶

UnitOfWork/NHibernateUnitOfWork.cs
Repositories/Repository.cs