The DataHandler class provides a consistent interface to data
available in many different sources and formats.
It manages simple stream to string conversions and related operations
using DataContentHandlers.
It provides access to commands that can operate on the data.
The commands are found using a CommandMap.
DataHandler and the Transferable Interface
DataHandler implements the Transferable interface so that data can
be used in AWT data transfer operations, such as cut and paste and
drag and drop. The implementation of the Transferable interface
relies on the availability of an installed DataContentHandler
object corresponding to the MIME type of the data represented in
the specific instance of the DataHandler.
DataHandler and CommandMaps
The DataHandler keeps track of the current CommandMap that it uses to
service requests for commands (getCommand
,
getAllCommands
, getPreferredCommands
).
Each instance of a DataHandler may have a CommandMap associated with
it using the setCommandMap
method. If a CommandMap was
not set, DataHandler calls the getDefaultCommandMap
method in CommandMap and uses the value it returns. See
CommandMap for more information.
DataHandler and URLs
The current DataHandler implementation creates a private
instance of URLDataSource when it is constructed with a URL.