"Java 2 (formerly JDK 1.2) introduced the ability to transfer data using the familiar drag and drop (D&D) metaphor. In Java 2, D&D utilizes the underlying data-transfer mechanism introduced in JDK 1.1 (java.awt.datatransfer) for use with the clipboard. Although this article discusses D&D operations in the context of GUI components, the specification includes no restrictions that prevent direct programmatic operations."
"If you need a single D&D-enabled component, you can create a subclass that defines DragGestureListener, DragSourceListener, and DropTargetListener as inner classes. This was the technique used in the first article. If you need a number of D&D-enabled components, you will write very similar code for each component's listeners."
"Listing 1's state variables and event handlers (responding to mouse-press, mouse-release, and mouse-drag events) collectively describe checker dragging. I won't delve into how those state variables and event handlers interact because a careful study of the source code and its many comments reveals how checker dragging works. However, there is one item that I want to discuss: flicker and its elimination."
"One of the new capabilities now available is improved data transfer support within and between applications. Data transfer includes two tasks: cut, copy, and paste access to the user or system clipboard and drag-and-drop support. Neither of these features is totally new to the standard library set. However, what you can do with them now in the 1.4 release and how you interact with the features has totally changed. Older programs, designed for the earlier data transfer mechanism, will continue to work fine, but in many cases the source code for the task can be simplified considerably."
