Icon inside button

Hello, icon iside the button dosn’t change its size.
My code is:

FileResource right = new FileResource(new File("right.png")); Image upT = new Image(); upT.setIcon(right); upT.setWidth("100%"); upT.setHeight("100%") Button takes all possible place in layout, but icon is bigger than button size.
What should I do to make Icon resize, accordingly button size&

Have you tried to set the image size with CSS?

Kind regards,