public class TestDemo {
      public static void main(String[] args) {
          String format = new DecimalFormat("##0.#######").format(10.000001);         System.out.println(format);         DecimalFormat f = new DecimalFormat("#,##0.00");         f.setRoundingMode(RoundingMode.HALF_UP);         String format1 = f.format(1.126);         System.out.println(format1);     } } output: 1.12

DecimalFormat f = new DecimalFormat("#,##0.00");

f.setRoundingMode(RoundingMode.HALF_UP); double d = 1.125; System.out.println(f.format(d)); // 输出 1.12

d = 1.135;

System.out.println(f.format(d)); // 输出 1.14

 

 

public static float div(int v1, int v2, int scale) { 

  if (v2 != 0) {     BigDecimal b1 = new BigDecimal(Double.toString(v1));     BigDecimal b2 = new BigDecimal(Double.toString(v2));     return b1.divid(b2,scale,BigDecimal.ROUND_HALF_UP).doubleValue();   } else {       return 0;   } } //scale表示保留几位小数