presto-main/src/main/java/io/prestosql/operator/aggregation/TypedHeap.java/TypedHeap/TypedHeap
class TypedHeap:    public TypedHeap(BlockComparator comparator, Type type, int capacity)
    {
        this.comparator = comparator;
        this.type = type;
        this.capacity = capacity;
        this.heapIndex = new int[capacity];
        this.heapBlockBuilder = type.createBlockBuilder(null, capacity);
    }