[java] Software Design With JOGL

Hello, Well, I am having issues with the way in which I should design a game using JOGL. What I am doing now is this: I have a project in which terrain is generated via a height map. Now, in my GameTerrain class I load the heightmap, generate all the normals, ect. However, in the public void display(GLDrawable gld) method within my GameRenderer class(which is obviously the GLEventListener) I am not sure whether I should use something like GameTerrain.render(gld) which would then get the gl object from within the render method of the GameTerrain class or if I should do something like vertexData = GameTerrain.getVertexList() from within the display() method itself and have all the gl function calls done within the display method instead of passing a gl object to the GameTerrain object and having the gl function calls done in the render method of said GameTerrain object. Am I making any sense here? Does it really matter? Or perhaps I am going about this all wrong in the first place? Anyhow, anyhelp anyone could give me would be very much appreciated. Thank you in advance.