Java 类it.unimi.dsi.fastutil.ints.Int2IntSortedMap 实例源码

/**
 * Given a table, generate the Next K items in Sorted Order starting from a specified
 * rowSnapShot (topRow), together with counts.
 * @param data The input table on which we want to compute the NextK list.
 * @return A NextKList.
 */
@Override
public NextKList create(ITable data) {
    IndexComparator comp = this.recordOrder.getComparator(data);
    IntTreeTopK topK = new IntTreeTopK(this.maxSize, comp);
    IRowIterator rowIt = data.getRowIterator();
    int i = rowIt.getNextRow();
    int position = 0;
    VirtualRowSnapshot vw = new VirtualRowSnapshot(data);
    while (i >= 0) {
        vw.setRow(i);
        if ((this.topRow == null) ||
                (this.topRow.compareTo(vw, this.recordOrder) <= 0))
            topK.push(i);
        else
            position++;
        i = rowIt.getNextRow();
    }
    Int2IntSortedMap topKList = topK.getTopK();
    IRowOrder rowOrder = new ArrayRowOrder(topKList.keySet());
    SmallTable topKRows = data.compress(this.recordOrder.toSubSchema(), rowOrder);
    List<Integer> count = new ArrayList<Integer>(topKList.size());
    count.addAll(topKList.values());
    return new NextKList(topKRows, count, position, data.getNumOfRows());
}

public Int2IntSortedMap getTopK() {
    final Int2IntSortedMap finalMap = new Int2IntRBTreeMap(this.greater);
    this.data.forEach((k, v) -> finalMap.put(k.intValue(), v.get()));
    return finalMap;
}