Question

I’m cropping a image in java swing, but when I select a part of image for cropping, I need to make selection part visible to user.
Like a transparent rectangle on that image.

Answer 1

GraphPanel shows one approach to rendering such a selection rectangle, mouseRect. The rendering is controlled by the boolean selecting attribute.

Addendum: Once you know the bounds of the selection, you can use getSubimage() to clone the corresponding part of the image. There’s a related example here.