Java 十进制格式舍入
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时间：2020-08-16 06:01:19 来源:igfitidea点击:
DecimalFormat rounding
提问by mainstringargs
Here is small code to illustrate what I am seeing
这是小代码来说明我所看到的
float floater = 59.999f;
DecimalFormat df = new DecimalFormat("00.0");
System.out.println(df.format(floater));
This prints:
这打印：
60.0
I would like it to print
我想打印
59.9
What do I need to do?
我需要做什么？
采纳答案by Michael Borgwardt
Add this line before using the DecimalFormat:
在使用之前添加这一行DecimalFormat：
df.setRoundingMode(RoundingMode.DOWN);
Take a look at the other rounding modes and see which one is best for you.
看看其他舍入模式，看看哪一种最适合您。
Note : this method works only in JDK 1.6 or above
注意：此方法仅适用于 JDK 1.6 或更高版本
回答by Pablo Fernandez
float d = 59.999f;
BigDecimal bd = new BigDecimal(d);
// Use the returned value from setScale, as it doesn't modify the caller.
bd = bd.setScale(1, BigDecimal.ROUND_FLOOR);
String formatted = bd.toString();
