@Override
public void begin(Transaction txn) {
// debug("%s begin", txn.getLabel()) ;
if (this.txn.getTxnId() != txn.getTxnId())
throw new TDBException(
String.format("Different transactions: %s %s", this.txn.getLabel(), txn.getLabel()));
if (passthrough) throw new TDBException("Already active");
passthrough = false;
allocOffset = base.allocOffset().getId();
// base node table empty e.g. first use.
journalObjFileStartOffset = journalObjFile.length();
// Because the data is written in prepare, the journal of object data is
// always empty at the start of a transaction.
if (journalObjFileStartOffset != 0)
warn(
log,
"%s journalStartOffset not zero: %d/0x%02X",
txn.getLabel(),
journalObjFileStartOffset,
journalObjFileStartOffset);
allocOffset += journalObjFileStartOffset;
this.nodeTableJournal = new NodeTableNative(nodeIndex, journalObjFile);
this.nodeTableJournal = NodeTableCache.create(nodeTableJournal, CacheSize, CacheSize, 100);
// This class knows about non-mappable inline values. mapToJournal(NodeId)/mapFromJournal.
this.nodeTableJournal = NodeTableInline.create(nodeTableJournal);
}
@Override
public void commitPrepare(Transaction txn) {
debug("commitPrepare");
// The node table is append-only so it can be written during prepare.
// The index isn't written (via the transaction journal) until enact.
if (nodeTableJournal == null)
throw new TDBTransactionException(
txn.getLabel() + ": Not in a transaction for a commit to happen");
writeNodeJournal();
if (journalObjFile != null && journalObjFile.length() != 0) {
long x = journalObjFile.length();
throw new TDBTransactionException(
txn.getLabel() + ": journalObjFile not cleared (" + x + ")");
}
}
private void writeNodeJournal() {
long expected = base.allocOffset().getId();
long len = journalObjFile.length();
if (expected != allocOffset)
warn(log, "Inconsistency: base.allocOffset() = %d : allocOffset = %d", expected, allocOffset);
long newbase = -1;
append(); // Calls all() which does a buffer flish.
// Reset (in case we use this again)
nodeIndex.clear();
journalObjFile.truncate(journalObjFileStartOffset); // Side effect is a buffer flush.
// journalObjFile.sync() ;
journalObjFile.close(); // Side effect is a buffer flush.
journalObjFile = null;
base.sync();
allocOffset =
-99; // base.allocOffset().getId() ; // Will be invalid as we may write through to the base
// table later.
passthrough = true;
}