- private final class ThreePhaseCommitImpl implements DOMStoreThreePhaseCommitCohort {
- private final SnapshotBackedWriteTransaction<String> transaction;
- private final DataTreeModification modification;
-
- private ResolveDataChangeEventsTask listenerResolver;
- private DataTreeCandidate candidate;
-
- public ThreePhaseCommitImpl(final SnapshotBackedWriteTransaction<String> writeTransaction, final DataTreeModification modification) {
- this.transaction = writeTransaction;
- this.modification = modification;
- }
-
- @Override
- public ListenableFuture<Boolean> canCommit() {
- try {
- dataTree.validate(modification);
- LOG.debug("Store Transaction: {} can be committed", transaction.getIdentifier());
- return CAN_COMMIT_FUTURE;
- } catch (ConflictingModificationAppliedException e) {
- LOG.warn("Store Tx: {} Conflicting modification for {}.", transaction.getIdentifier(),
- e.getPath());
- warnDebugContext(transaction);
- return Futures.immediateFailedFuture(new OptimisticLockFailedException("Optimistic lock failed.", e));
- } catch (DataValidationFailedException e) {
- LOG.warn("Store Tx: {} Data Precondition failed for {}.", transaction.getIdentifier(),
- e.getPath(), e);
- warnDebugContext(transaction);
-
- // For debugging purposes, allow dumping of the modification. Coupled with the above
- // precondition log, it should allow us to understand what went on.
- LOG.trace("Store Tx: {} modifications: {} tree: {}", modification, dataTree);
-
- return Futures.immediateFailedFuture(new TransactionCommitFailedException("Data did not pass validation.", e));
- } catch (Exception e) {
- LOG.warn("Unexpected failure in validation phase", e);
- return Futures.immediateFailedFuture(e);
- }
- }
-
- @Override
- public ListenableFuture<Void> preCommit() {
- try {
- candidate = dataTree.prepare(modification);
- listenerResolver = ResolveDataChangeEventsTask.create(candidate, listenerTree);
- return SUCCESSFUL_FUTURE;
- } catch (Exception e) {
- LOG.warn("Unexpected failure in pre-commit phase", e);
- return Futures.immediateFailedFuture(e);
- }
- }
-
- @Override
- public ListenableFuture<Void> abort() {
- candidate = null;
- return SUCCESSFUL_FUTURE;
- }
-
- @Override
- public ListenableFuture<Void> commit() {
- checkState(candidate != null, "Proposed subtree must be computed");
-
- /*
- * The commit has to occur atomically with regard to listener
- * registrations.
- */
- synchronized (InMemoryDOMDataStore.this) {
- dataTree.commit(candidate);
- changePublisher.publishChange(candidate);
- listenerResolver.resolve(dataChangeListenerNotificationManager);
- }