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

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).

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new DecimalFormat("#.##").format(1.199); //"1.2"

As pointed in the comments, this is not the right answer to the original question.
That said, it is a very useful way to format numbers without unnecessary trailing zeros.


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