Module java.rmi

Class RMISocketFactory

  • All Implemented Interfaces:
    RMIClientSocketFactory, RMIServerSocketFactory

    public abstract class RMISocketFactory
    extends Object
    implements RMIClientSocketFactory, RMIServerSocketFactory
    An RMISocketFactory instance is used by the RMI runtime in order to obtain client and server sockets for RMI calls. An application may use the setSocketFactory method to request that the RMI runtime use its socket factory instance instead of the default implementation.

    The default socket factory implementation creates a direct socket connection to the remote host.

    The default socket factory implementation creates server sockets that are bound to the wildcard address, which accepts requests from all network interfaces.

    Implementation Note:

    You can use the RMISocketFactory class to create a server socket that is bound to a specific address, restricting the origin of requests. For example, the following code implements a socket factory that binds server sockets to an IPv4 loopback address. This restricts RMI to processing requests only from the local host.

    
         class LoopbackSocketFactory extends RMISocketFactory {
             public ServerSocket createServerSocket(int port) throws IOException {
                 return new ServerSocket(port, 5, InetAddress.getByName("127.0.0.1"));
             }
    
             public Socket createSocket(String host, int port) throws IOException {
                 // just call the default client socket factory
                 return RMISocketFactory.getDefaultSocketFactory()
                                        .createSocket(host, port);
             }
         }
    
         // ...
    
         RMISocketFactory.setSocketFactory(new LoopbackSocketFactory());
     
    Set the java.rmi.server.hostname system property to 127.0.0.1 to ensure that the generated stubs connect to the right network interface.
    Since:
    1.1
    • Constructor Detail

      • RMISocketFactory

        public RMISocketFactory()
        Constructs an RMISocketFactory.
        Since:
        1.1
    • Method Detail

      • createSocket

        public abstract Socket createSocket​(String host,
                                            int port)
                                     throws IOException
        Creates a client socket connected to the specified host and port.
        Specified by:
        createSocket in interface RMIClientSocketFactory
        Parameters:
        host - the host name
        port - the port number
        Returns:
        a socket connected to the specified host and port.
        Throws:
        IOException - if an I/O error occurs during socket creation
        Since:
        1.1
      • createServerSocket

        public abstract ServerSocket createServerSocket​(int port)
                                                 throws IOException
        Create a server socket on the specified port (port 0 indicates an anonymous port).
        Specified by:
        createServerSocket in interface RMIServerSocketFactory
        Parameters:
        port - the port number
        Returns:
        the server socket on the specified port
        Throws:
        IOException - if an I/O error occurs during server socket creation
        Since:
        1.1
      • setSocketFactory

        public static void setSocketFactory​(RMISocketFactory fac)
                                     throws IOException
        Set the global socket factory from which RMI gets sockets (if the remote object is not associated with a specific client and/or server socket factory). The RMI socket factory can only be set once. Note: The RMISocketFactory may only be set if the current security manager allows setting a socket factory; if disallowed, a SecurityException will be thrown.
        Parameters:
        fac - the socket factory
        Throws:
        IOException - if the RMI socket factory is already set
        SecurityException - if a security manager exists and its checkSetFactory method doesn't allow the operation.
        Since:
        1.1
        See Also:
        getSocketFactory(), SecurityManager.checkSetFactory()
      • getSocketFactory

        public static RMISocketFactory getSocketFactory()
        Returns the socket factory set by the setSocketFactory method. Returns null if no socket factory has been set.
        Returns:
        the socket factory
        Since:
        1.1
        See Also:
        setSocketFactory(RMISocketFactory)
      • getDefaultSocketFactory

        public static RMISocketFactory getDefaultSocketFactory()
        Returns a reference to the default socket factory used by this RMI implementation. This will be the factory used by the RMI runtime when getSocketFactory returns null.
        Returns:
        the default RMI socket factory
        Since:
        1.1
      • setFailureHandler

        public static void setFailureHandler​(RMIFailureHandler fh)
        Sets the failure handler to be called by the RMI runtime if server socket creation fails. By default, if no failure handler is installed and server socket creation fails, the RMI runtime does attempt to recreate the server socket.

        If there is a security manager, this method first calls the security manager's checkSetFactory method to ensure the operation is allowed. This could result in a SecurityException.

        Parameters:
        fh - the failure handler
        Throws:
        SecurityException - if a security manager exists and its checkSetFactory method doesn't allow the operation.
        Since:
        1.1
        See Also:
        getFailureHandler(), RMIFailureHandler.failure(Exception)