JOGL problem

hey i ve got a problem with JOGL(Java + openGL). I have created a hero that the user controls. any ideas how i can make it move to explore an area? till now i have achieved to make him move forward and rotate its body but when it rotates and i press the forward key again it keeps on moving in the same direction as before the rotation but with its body rotated.

i tried s1 = (float)Math.cos(rotate%360)
and s2 = (float)Math.sin(rotate%360)

but now when i hit 'a' or 'd' the whole screen rotates not just the object!