A program calling method is to be implemented by a control module, which uses a first channel during execution of a first Java applet, and includes creating a virtual channel that corresponds to a second channel when the first Java applet intends to call a second Java applet which is to be executed using the second channel, in response to a channel management instruction associated with the virtual channel, opening the second channel for allowing execution of the second Java applet, determining whether the virtual channel is still open, and receiving an output from the second Java applet for use by the first Java applet when it is determined that the virtual channel is still open.