If this value is true and the java.rmi.server.disableHttp
system property is not set, then RMI's default socket factory will fall back to HTTP tunneling when any java.net.SocketException
is thrown from an initial (direct) connection attempt, as opposed to the default behavior of falling back to HTTP tunneling only if an initial connection attempt throws a java.net.UnknownHostException
or java.net.NoRouteToHostException
.
This setting can be useful when dealing with firewalls that deny (instead of ignore) connection attempts to unauthorized ports, resulting in java.net.ConnectionException
s inside the client's default RMI socket factory. If this system property is not enabled, then such ConnectionException
s will not trigger HTTP fallback, since they are neither UnknownHostException
s nor NoRouteToHostException
s. However, if this system property is enabled, then the ConnectionException
s will cause HTTP fallback to occur, because ConnectionException
is a subclass of SocketException
.