I have managed to build my first java application which generates a sequence of numbers, formats them as a string (i.e. 10 reads as 00010), adds a delimiter and outputs them to a text file.

This all works however the performance is atrocious! I have tried several ways of generating my output string but none of them come close to the same application I wrote in perl.

Bearing in mind I am aiming to generate a text file with numbers of up to 1000000 what suggestions does anyone have as to the best way to accomplish this?