public class FormatRubles { String Rubles(float sum) { int sum1 = (int) Math.floor(sum); if (sum1 > 100) sum1 %= 100; if (sum1 > 20) sum1 %= 10; switch (sum1) { case 1: return "рубль"; case 2: case 3: case 4: return "рубля"; default: return "рублей"; } } }