Zero Configuration Networking: The Definitive Guide

Chapter 8. Using the Java APIs

Starting in Mac OS X 10.3.9, new APIs enable Java software to advertise and discover services on the network using Zeroconf’s DNS Service Discovery. The same Java DNS-SD APIs are also available in Bonjour for Windows, Bonjour for Linux, Solaris, *BSD, etc., enabling Java software to make use of Zeroconf’s DNS Service Discovery across a wide range of platforms, not just on Mac OS X. In this chapter, you will take a quick look through the APIs, see short examples of how to register, browse for, add TXT records to, and resolve services, and finally see a complete example of using Java DNS-SD in a tic-tac-toe game.

Understanding the APIs

The com.apple.dnssd package exposes an abstract factory class, DNSSD, used to create the various types of DNSSDService objects, two classes used to manipulate DNS records, a collection of interfaces that are implemented as appropriate by client code to receive callback messages, and an exception:

• Factory Class :

  • DNSSD

• References to ongoing asynchronous operations :

  • DNSSDService

  • DNSSDRegistration

• DNS Record Classes:

  • DNSRecord

  • TXTRecord

• Callback Interface Classes , implemented by client:

  • BaseListener

  • RegisterListener

  • BrowseListener

  • ResolveListener

  • DomainListener

  • QueryListener

• DNSSD Error Exception:

  • DNSSDException

The pattern for using the APIs will most often consist of calling a static method from the DNSSD factory class, passing in an instance of a class that implements the appropriate interface to receive callback ...