Poiで便利なロジック

英語表記で指定したセルを数値に変換する
例）A　  　0
      AA　　26

public class Sample2 {

    public static void main(String[] args) {
        Sample2 sample2 = new Sample2();
        System.out.println(sample2.sample("BA"));
    }

    private int sample(String val){
        int result = 0;
        // 桁数
        int length = val.length();
        StringBuilder builder = new StringBuilder(val);
        builder.reverse();
        String temp = builder.toString();
        for (int i = 0; i < length; i++) {
            char c = temp.charAt(i);
            int num = this.sample(c);
            result += num * Math.pow(26, i);
        }
        return result - 1;
    }

    private int sample(char val) {
        int result = 0;
        for (int i = 'A', count = 1; i <= 'Z'; i++, count++) {
            if (val == i) {
                result = count;
                break;
            }
        }
        return result;
    }
}