Java Network Programming, Second Edition

Creating Secure Client Sockets

If you don’t care very much about the underlying details, using an encrypted SSL socket to talk to an existing secure server is truly straightforward. Rather than constructing a java.net.Socket object with a constructor, you get one from a javax.net.ssl.SSLSocketFactory by using its createSocket( ) method. SSLSocketFactory is an abstract class that follows the abstract factory design pattern:

public abstract class SSLSocketFactory extends SocketFactory

Since the SSLFactorySocket class is itself abstract, you get an instance of it by invoking the static SSLSocketFactory.getDefault( ) method:

public static SocketFactory getDefault(  ) throws InstantiationException

This either returns an instance of SSLSocketFactory or throws an InstantiationException if no concrete subclass can be found. Once you have a reference to the factory, use one of the five overloaded createSocket( ) methods to build an SSLSocket:

public abstract Socket createSocket(String host, int port) throws IOException, UnknownHostException public abstract Socket createSocket(InetAddress host, int port) throws IOException public abstract Socket createSocket(String host, int port, InetAddress interface, int localPort) throws IOException, UnknownHostException public abstract Socket createSocket(InetAddress host, int port, InetAddress interface, int localPort) throws IOException, UnknownHostException public abstract Socket createSocket(Socket proxy, String host, int port, boolean autoClose) ...