Examples with CloseableIterator org.apache.druid.java.util.common.parsers.CloseableIterator used on opensource projects

Example 16 with CloseableIterator

use of org.apache.druid.java.util.common.parsers.CloseableIterator in project druid by druid-io.

the class HashVectorGrouper method iterator.

@Override
public CloseableIterator<Grouper.Entry<Memory>> iterator() {
    if (!initialized) {
        // a nested groupBy's subquery has an empty result set (see testEmptySubquery() in GroupByQueryRunnerTest)
        return CloseableIterators.withEmptyBaggage(Collections.emptyIterator());
    }
    final IntIterator baseIterator = hashTable.bucketIterator();
    return new CloseableIterator<Grouper.Entry<Memory>>() {

        @Override
        public boolean hasNext() {
            return baseIterator.hasNext();
        }

        @Override
        public Grouper.Entry<Memory> next() {
            final int bucket = baseIterator.nextInt();
            final int bucketPosition = hashTable.bucketMemoryPosition(bucket);
            final Memory keyMemory = hashTable.memory().region(bucketPosition + hashTable.bucketKeyOffset(), hashTable.keySize());
            final Object[] values = new Object[aggregators.size()];
            final int aggregatorsOffset = bucketPosition + hashTable.bucketValueOffset();
            for (int i = 0; i < aggregators.size(); i++) {
                values[i] = aggregators.get(hashTable.memory().getByteBuffer(), aggregatorsOffset, i);
            }
            return new Grouper.Entry<>(keyMemory, values);
        }

        @Override
        public void close() {
        // Do nothing.
        }
    };
}