Java Graph

I'm trying to make a graph to put into a JPanel or JFrame, but my coordinates are huge. The range on my x-axis are 0 - 1024 and the y axis range is 0 - 300.
I plotted it using a polyline, but that was a fucking disaster. How do you graph coordinates and then modify the graph to keep the points relative (so I could have a graph that's 500px X 500px that has 1024 points)?

x = x / 1024.0 * 500.0
y = y / 300.00 * 500.0
path.add(x,y)