Handling long strings - Advice needed

Being an old fashioned programmer (retired 12 years ago) I am used to VB and string handling was not so complicated as its become for developing web sites. I run a independent developer community for the wall.fm and oxwall community software packages, mostly dealing with CSS. I have thrown myself at the wall so to speak and back at playing with code.

My problem is that I need to split some code in to to string segments and place a string in the center of the pile so to speak: First_string.... Last_String then an input String (A Url to a image file) so I have the following result.

Endproduct = FirstString + InputUrl + Last_string

The Endproduct needs to go into a text form (its an ebedded code to be used by a mermber of a community to copy and past as a background image in their profile page)

So far I have used StringBuffer and now sitting back thinking what next?

The two strings concerned and further information and my results can be found at this link.

I think this problem will invite interest to the most creative experienced Java guri's because of the source strings are complex and need special handling. I rather hope that's the case.

Your help will be much appreciated.

Best wishes for the year 2011

Bob Johnson-Perkins
Code.wall.fm