Interface to be implemented by a component that interacts with transaction logic.
The client code that uses transaction logic looks like this:
TransactionAware dataSet = // ... // dataSet is one example of component that interacts with tx logic
Transaction tx = txClient.start();
dataSet.startTx(tx); // notifying about new transaction
dataSet.write(...);
// ... do other operations on dataSet
Collection changes = dataSet.getTxChanges();
boolean rollback = true;
if (txClient.canCommit(changes)) { // checking conflicts before commit, if none, commit tx
if (dataSet.commitTx()) { // try persisting changes
if (txClient.commit(tx)) { // if OK, make tx visible; if not - tx stays invisible to others
dataSet.postTxCommit(); // notifying dataset about tx commit success via callback
rollback = false;
}
}
}
if (rollback) { // if there are conflicts (or cannot commit), try rollback changes
if (dataSet.rollbackTx()) { // try undo changes
txClient.abort(tx); // if OK, make tx visible; if not - tx stays invisible to others
}
}