I'm having some trouble understanding your question. I'm guessing you're making a line chart and you want the scale of the time axis to compress, presumably as you add more data. Is that about right? What problems are you having?
Also, please read our article on isolating the problem. Unfortunately, posting 100 lines of code or more usually scares everyone away and pretty much guarantees that no one will help you.
Since this question isn't related to Java IO and since JFreeChart seems to be free and open source, I'll move this thread over to our "Other Open Source Projects" forum.
I do have a couple of a recommendations though. Start with with simplest example you can and get that working. Then gradually add features that you want it to have. If you get stuck adding a particular feature, then you can ask about that. There are few online communities as eagerly helpful as JavaRanch, but you have to provide more details than, "It's not working."
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