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# Numberformater or substring or ????

Frank Jacobsen
Ranch Hand
Posts: 358
If have a string that looks like this:

String test = "111122223333444";

I have to convert this string to:

String result = "1111-2222-3333-4444";

I now i can do this very easy, when i take a sbbstring 4 times like this:

But is there a easyer or better way, maybe with NumberFormatter, im running java 1.3 ???

Frank Jacobsen

Leo Deegan
Greenhorn
Posts: 12
Hi there Frank,

I'm not sure what your parsing rules are exactly, but I'm guessing that you want a dash between every grouping of four digits for a number that is 16 digits long. A number that large can be handled by a java.math.BigDecimal. Here's my main method to test out a DecimalFormat approach (sorry, I did this in JDK 1.4.2, but try it out in 1.3 and see if it works):

Jim Yingst
Wanderer
Sheriff
Posts: 18671
One problem here is, what if the number begins with zeros? E.g. "0000111122223333" will be written as "1111-2222-3333", which probably isn't what you'd want. It's possible to write code to prepend 0's and -'s as necessary, but this will end up being more complex than the initial solution with substring.

One possible problem with the substring() approach - is it possible that the string might be less than 12 digits? If the input is "123456", is that an error? Or should that be rendered as "0000-0012-3456"? The latter will require some extra coding. Hopefully this is an erroneous input you don't have to deal with, but it might be worth considering.

Frank Jacobsen
Ranch Hand
Posts: 358
Thanks

That helpt me a lot !

Frank

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