presto-orc/src/main/java/io/prestosql/orc/stream/BooleanInputStream.java/BooleanInputStream/getSetBits
class BooleanInputStream:    public byte[] getSetBits(int batchSize)
            throws IOException
    {
        byte[] vector = new byte[batchSize];
        getSetBits(vector, batchSize);
        return vector;
    }