Setting an Accessible Name for an Image Button
You should also set the accessible name for components that only show an image. The tool tip text, if set, serves as the accessible name for a component. However, if the tool tip text is being used for something else, set the component's accessible name. 

    
 JButton button = new JButton(new ImageIcon("image.gif"));
 button.setToolTipText("Button Name");
     
 // If tool tip is being used for something else,
 // set the accessible name.
 button.getAccessibleContext().setAccessibleName(
   "Button Name");