public void testBackwardIteration() throws IOException {
final int records = 10000;
long seed = System.currentTimeMillis();
MersenneTwisterFast mersenneTwisterFast = new MersenneTwisterFast(1381162033616L);
System.out.println("testBackwardIteration seed : " + seed);
NavigableMap<OClusterPosition, byte[]> positionRecordMap = new TreeMap<OClusterPosition, byte[]>();
ORecordVersion recordVersion = OVersionFactory.instance().createVersion();
recordVersion.increment();
recordVersion.increment();
for (int i = 0; i < records; i++) {
int recordSize = mersenneTwisterFast.nextInt(2 * OClusterPage.MAX_RECORD_SIZE) + 1;
byte[] record = new byte[recordSize];
mersenneTwisterFast.nextBytes(record);
final OPhysicalPosition physicalPosition = paginatedCluster.createRecord(record, recordVersion, (byte) 2);
positionRecordMap.put(physicalPosition.clusterPosition, record);
}
Iterator<OClusterPosition> positionIterator = positionRecordMap.keySet().iterator();
while (positionIterator.hasNext()) {
OClusterPosition clusterPosition = positionIterator.next();
if (mersenneTwisterFast.nextBoolean()) {
Assert.assertTrue(paginatedCluster.deleteRecord(clusterPosition));
positionIterator.remove();
}
}
OPhysicalPosition physicalPosition = new OPhysicalPosition();
physicalPosition.clusterPosition = OClusterPositionFactory.INSTANCE.valueOf(Long.MAX_VALUE);
OPhysicalPosition[] positions = paginatedCluster.floorPositions(physicalPosition);
Assert.assertTrue(positions.length > 0);
positionIterator = positionRecordMap.descendingKeySet().iterator();
int counter = 0;
while (positionIterator.hasNext()) {
Assert.assertTrue(positions.length > 0);
OClusterPosition testedPosition = positionIterator.next();
Assert.assertEquals(positions[positions.length - 1].clusterPosition, testedPosition);
OPhysicalPosition positionToFind = positions[positions.length - 1];
positions = paginatedCluster.lowerPositions(positionToFind);
counter++;
}
Assert.assertEquals(paginatedCluster.getEntries(), counter);
Assert.assertEquals(paginatedCluster.getFirstPosition(), positionRecordMap.firstKey());
Assert.assertEquals(paginatedCluster.getLastPosition(), positionRecordMap.lastKey());
}
