double f = 111231.035; BigDecimal l = new BigDecimal(f); double c = l.setScale(2, RoundingMode.HALF_UP).doubleValue(); System.out.println("返回值:"+c)
double d = 323.5627614; DecimalFormat format = new DecimalFormat("#.000"); String c = format.format(d); System.out.println("格式化后 "+c); 格式化后 323.563
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