How to nicely format floating numbers to string without unnecessary decimal 0's

Question

A 64-bit double can represent integer +/- 2⁵³ exactly.

Given this fact, I choose to use a double type as a single type for all my types, since my largest integer is an unsigned 32-bit number.

But now I have to print these pseudo integers, but the problem is they are also mixed in with actual doubles.

So how do I print these doubles nicely in Java?

I have tried String.format("%f", value), which is close, except I get a lot of trailing zeros for small values.

Here's an example output of of %f

 232.00000000 0.18000000000 1237875192.0 4.5800000000 0.00000000 1.23450000 

What I want is:

 232 0.18 1237875192 4.58 0 1.2345 

Sure I can write a function to trim those zeros, but that's lot of performance loss due to string manipulation. Can I do better with other format code?

---

The answers by Tom E. and Jeremy S. are unacceptable as they both arbitrarily rounds to two decimal places. Please understand the problem before answering.

---

Please note that String.format(format, args...) is locale-dependent (see answers below).

Answer 1

If the idea is to print integers stored as doubles as if they are integers, and otherwise print the doubles with the minimum necessary precision:

public static String fmt(double d) {     if(d == (long) d)         return String.format("%d",(long)d);     else         return String.format("%s",d); } 

Produces:

232 0.18 1237875192 4.58 0 1.2345 

And does not rely on string manipulation.

Answer 2

String.format("%.2f", value);