Create multiple polygons (Bar chart) with JOGL

Hello,

I'm working on a project for school and am completely stumped. OpenGL is required and seems great but I have no idea how to code multiple objects/polygons. I can get one object to appear but need to create multiple (8) objects based on a dataset. My goal is to read a datafile and create a bar chart based on certain attributes. I'm using Java since I'm most familiar with that but if you have advice or snippets of code I could see to understand how to create a bar chart (or similar) I'd greatly appreciate it. Thanks!

~Jennifer