/** Initialize the scan, returning false if there was some error. */
public boolean init(TransactionManager tran) throws StandardException {
if (SanityManager.DEBUG) {
// We really expect to have at least one
// merge run.
SanityManager.ASSERT(mergeRuns != null);
SanityManager.ASSERT(mergeRuns.size() > 0);
// This sort scan also expects that the
// caller has ensured that the sort buffer
// capacity will hold a row from all the
// merge runs.
SanityManager.ASSERT(sortBuffer.capacity() >= mergeRuns.size());
}
// Clear the sort buffer.
sortBuffer.reset();
// Create an array to hold a scan controller
// for each merge run.
openScans = new StreamContainerHandle[mergeRuns.size()];
if (openScans == null) return false;
// Open a scan on each merge run.
int scanindex = 0;
Enumeration e = mergeRuns.elements();
while (e.hasMoreElements()) {
// get the container id
long id = ((Long) e.nextElement()).longValue();
Transaction rawTran = tran.getRawStoreXact(); // get raw transaction
int segmentId = StreamContainerHandle.TEMPORARY_SEGMENT;
openScans[scanindex++] = rawTran.openStreamContainer(segmentId, id, hold);
}
// Load the initial rows.
for (scanindex = 0; scanindex < openScans.length; scanindex++) mergeARow(scanindex);
// Success!
return true;
}
