Hello all, could anybody tell me how to zoom in/out images
and lines?

I want to create a application like google maps or mapquest,
find the shortest path between two points in the image, then draw
the path in the image,

After drawing the shortest path, user need to zoom in/out the
direction map,
so I need to zoom in/out the .jpg image, from my research, seems that
I can use AffineTransform to zoom in/out the image, but how can I
redraw the
path(lines) in the picture?

Also, after zoom in, the user also need to see different parts of the
whole picture,
for example, use can click up/down/left/right button to see different
parts of the map?

Thank you for any ideas or example code.