There are two ways to implement a clipboard. One method uses a private clipboard that only the applet or application can use. The other is to use the system clipboard and share data with all other applications that can access the clipboard. Both methods are described here.
A private clipboard is probably best if you're just manipulating data within a single application. You won't run the risk of a conflict with another application where the data you expect is gone or altered.
The system clipboard is essential if you're planning to share data between applications.
One thing to remember is that a private Clipboard object must remain in scope during the period when you need to retrieve data. A Clipboard object that goes out ...