Way to get number of digits in an int?

java integer
fnst picture fnst · Aug 20, 2009 · Viewed 576.1k times · Source

Is there a neater way for getting the number of digits in an int than this method?

int numDigits = String.valueOf(1000).length();

Answer

Michael Borgwardt picture Michael Borgwardt · Aug 20, 2009

Your String-based solution is perfectly OK, there is nothing "un-neat" about it. You have to realize that mathematically, numbers don't have a length, nor do they have digits. Length and digits are both properties of a physical representation of a number in a specific base, i.e. a String.

A logarithm-based solution does (some of) the same things the String-based one does internally, and probably does so (insignificantly) faster because it only produces the length and ignores the digits. But I wouldn't actually consider it clearer in intent - and that's the most important factor.

Related questions

How do I generate random integers within a specific range in Java?

How do I generate a random int value in a specific range? I have tried the following, but those do not work: Attempt 1: randomNum = minimum + (int)(Math.random() * maximum); // Bug: `randomNum` can be bigger than `maximum`. Attempt 2: Random rn = new …

Read More
max value of integer

In C, the integer (for 32 bit machine) is 32 bits, and it ranges from -32,768 to +32,767. In Java, the integer(long) is also 32 bits, but ranges from -2,147,483,648 to +2,147,483,647. I do not understand how the range is different in Java, even …

Read More
How to get the separate digits of an int number?

I have numbers like 1100, 1002, 1022 etc. I would like to have the individual digits, for example for the first number 1100 I want to have 1, 1, 0, 0. How can I get it in Java?

Read More