OpenGL Normals (java)

[mclarenv8]

Hey guys, sorry need some more help, im slightly confused

I have this code for a normal constructor in a class that works when you enter 4 vectors, I also have one for 3 vector shapes like triangles which i wont include here.

But how can i stretch this for 5 or 6 vectors??? I dont know what order to do the numbers in, in the code..

code:

public Normal(Vector vector1, Vector vector2, Vector vector3, Vector vector4)     {         x = (vector1.getY()-vector2.getY())*(vector1.getZ()+vector2.getZ()) +             (vector2.getY()-vector3.getY())*(vector2.getZ()+vector3.getZ()) +             (vector3.getY()-vector4.getY())*(vector3.getZ()+vector4.getZ()) +             (vector4.getY()-vector1.getY())*(vector4.getZ()+vector1.getZ());         y = (vector1.getZ()-vector2.getZ())*(vector1.getX()+vector2.getX()) +             (vector2.getZ()-vector3.getZ())*(vector2.getX()+vector3.getX()) +             (vector3.getZ()-vector4.getZ())*(vector3.getX()+vector4.getX()) +             (vector4.getZ()-vector1.getZ())*(vector4.getX()+vector1.getX());         z = (vector1.getX()-vector2.getX())*(vector1.getY()+vector2.getY()) +             (vector2.getX()-vector3.getX())*(vector2.getY()+vector3.getY()) +             (vector3.getX()-vector4.getX())*(vector3.getY()+vector4.getY()) +             (vector4.getX()-vector1.getX())*(vector4.getY()+vector1.getY());                 normalise();            }