java计算整型相除后小数再四舍五入得到整型数值

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public class PercentCalculateUtils {

private static final Integer HUNDRED = 100;

  public Integer getPercent(Integer num, Integer sum) {

      Integer percent = sum == 0 ? 0 :
            new BigDecimal(num)   //创建BigDecimal对象
                    .divide(new BigDecimal(sum), 2, RoundingMode.DOWN)  //保留2位小数
                    .multiply(new BigDecimal(HUNDRED)) //小数乘以100
                    .intValue(); //转成Integer

     return percent;
  }
  // 将乘法的结果四舍五入
  public  static Integer testMultiply(){
   int money = new BigDecimal(
           new BigDecimal(2510).multiply(new BigDecimal(0.24)).doubleValue())
           .setScale(0, BigDecimal.ROUND_HALF_UP).intValue();
    return money;
}

}

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    @Test
    public void testPer(){
        System.out.println("percent : "+getPercent(1,3));
    }

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percent : 33