Start data transfer from ContentProvider
start( is called each time
MATLAB® is ready to start the transfer of a data stream by calling
getData one or more times. Each time this is called, the provider
is expected to reset so that the next call to
getData goes back to the
beginning of the data stream.
start indicates that a connection to the server has been
established and transfer of data is about to start. A subsequent call to
start (without an intervening call to the
method) might indicate that the server requested a redirect to a different server, or
requires another try with authentication credentials, and this could occur before,
during, or after transmission of the data stream.
If your provider is restartable, reset your provider so that the next call to
getData returns to the beginning of the data stream, and insure
restartable method returns
If your provider is not restartable for the same message, but can be reused for a new
restartable returns false.
Subclasses that override this method should always call their superclass method first.
If the provider was already started and is not restartable, then
throws an exception by default.
This method is the best place to implement costly initialization that is not needed
until the server is ready to receive data, as opposed to the
method, which must do initialization necessary to create the message header. If the
server cannot be contacted or rejects the message, then MATLAB does not call
provider— Content provider
Content provider, specified as a