我如何使用 String.format() 在 Java 中格式化双打

Question

I am trying to format double the same way as this but my Java is giving me an "IllegalFormatPrecisionException". How do I fix this.

public static void main(String[] args) {
    double t = 321.4532;
    String str = String.format("%.1d", t);
}    

Answer 1

%d is used for integer values try using

public static void main(String[] args) {
    double t = 321.4532;
    String str = String.format("%.1f", t);
}  

Answer 2

Quoting from this [site][1]:

Don't try to use "d" for double here, because that is used to format integer and stands for decimal in formatting instruction.

Use %.2f and you will be good.

[1]: https://www.java67.com/2014/06/how-to-format-float-or-double-number-java-example.html#:~:text=format(%22%25.,float%20data%20type%20in%20Java.