保留小数位与只保留整数 发表于 2016-08-01 常用的几种小数位操作方法 保留小数位1234567891011121314151617181920212223242526272829303132333435double f = 111231.5585;@Testpublic void demo1() { BigDecimal bigDecimal = new BigDecimal(f); //四舍六入五凑偶 f = bigDecimal.setScale(3, RoundingMode.HALF_UP).doubleValue(); System.out.println(f);}@Testpublic void demo2() { //四舍六入五凑偶 DecimalFormat df = new DecimalFormat("#.000"); String f2 = df.format(f); double f3 = Double.valueOf(f2); System.out.println(f3);}@Testpublic void demo3() { //四舍五入 String ff = String.format("%.3f", f); System.out.println(ff);}@Testpublic void demo4() { //四舍六入五凑偶 NumberFormat nf = NumberFormat.getNumberInstance(); nf.setMaximumFractionDigits(3); String ff = nf.format(f); System.out.println(ff);} 只保留整数位1234567double f = 111231.5585;@Testpublic void demo5() { Double d = Double.valueOf(f); //只保留整数位,小数位直接舍弃 System.out.println(d.intValue());}