A FocusListener object is registered via addFocusListener. They shall be added onto the content-pane of the top-level container.

Javadoc can be used to describe information at the package, class, member and method level. Makes this Component undisplayable by destroying it native screen resource. The Image object is used in the drawImage method for custom drawing which shall be discussed later.

They shall be added onto the content-pane of the top-level container. If listener is null , no exception is thrown and no action is performed.