Java™ How To Program (Early Objects), Tenth Edition

Server Class

Class Server (Fig. 28.7) declares two DatagramPackets that the server uses to send and receive information and one DatagramSocket that sends and receives the packets. The constructor (lines 19–37), which is called from main (Fig. 28.8, lines 7–12), creates the GUI in which the packets of information will be displayed. Line 30 creates the DatagramSocket in a try block. Line 30 in Fig. 28.7 uses the DatagramSocket constructor that takes an integer port-number argument (5000 in this example) to bind the server to a port where it can receive packets from clients. Clients sending packets to this Server specify the same port number in the packets they send. A SocketException is thrown if the DatagramSocket constructor fails to bind the ...