Examples with KVIterator io.mycat.memory.unsafe.KVIterator used on opensource projects

Example 1 with KVIterator

use of io.mycat.memory.unsafe.KVIterator in project Mycat-Server by MyCATApache.

the class UnsafeFixedWidthAggregationMap method iterator.

/**
   * Returns an iterator over the keys and values in this map. This uses destructive iterator of
   * BytesToBytesMap. So it is illegal to call any other method on this map after `iterator()` has
   * been called.
   *
   * For efficiency, each call returns the same object.
   */
public KVIterator<UnsafeRow, UnsafeRow> iterator() {
    return new KVIterator<UnsafeRow, UnsafeRow>() {

        private final BytesToBytesMap.MapIterator mapLocationIterator = map.iterator();

        private final UnsafeRow key = new UnsafeRow(groupingKeySchema.length());

        private final UnsafeRow value = new UnsafeRow(aggregationBufferSchema.length());

        @Override
        public boolean next() {
            if (mapLocationIterator.hasNext()) {
                final BytesToBytesMap.Location loc = mapLocationIterator.next();
                if (loc == null)
                    return false;
                key.pointTo(loc.getKeyBase(), loc.getKeyOffset(), loc.getKeyLength());
                value.pointTo(loc.getValueBase(), loc.getValueOffset(), loc.getValueLength());
                return true;
            } else {
                return false;
            }
        }

        @Override
        public UnsafeRow getKey() {
            return key;
        }

        @Override
        public UnsafeRow getValue() {
            return value;
        }

        @Override
        public void close() {
        }
    };
}