odbtest/test/arrow/memory.go

package main

import (
	"fmt"

	"github.com/apache/arrow/go/arrow/array"
	"github.com/apache/arrow/go/arrow/memory"
)

func main() {
	// create LSB packed bits with the following pattern:
	// 01010011 11000101
	data := memory.NewBufferBytes([]byte{0xca, 0xa3})

	// create LSB packed validity (null) bitmap, where every 4th element is null:
	// 11101110 11101110
	nullBitmap := memory.NewBufferBytes([]byte{0x77, 0x77})

	// Create a boolean array and lazily determine NullN using UnknownNullCount
	bools := array.NewBoolean(16, data, nullBitmap, array.UnknownNullCount)
	defer bools.Release()

	// Show the null count
	fmt.Printf("NullN()  = %d\n", bools.NullN())

	// Enumerate the values.
	n := bools.Len()
	for i := 0; i < n; i++ {
		fmt.Printf("bools[%d] = ", i)
		if bools.IsNull(i) {
			fmt.Println("(null)")
		} else {
			fmt.Printf("%t\n", bools.Value(i))
		}
	}

}