Refactor SshProxyServer class

Adapt SshProxyServer to deal with
apache/mina-sshd#424

JIRA: NETCONF-1267
Change-Id: I254c8fa2563553a22e3197b658bb0c367c51e232
Signed-off-by: Matej Sramcik <matej.sramcik@pantheon.tech>

apps/netconf-nb/src/main/java/org/opendaylight/netconf/northbound/ssh/SshProxyServer.java

@@ -33,11 +33,11 @@
 import org.opendaylight.netconf.shaded.sshd.common.io.IoServiceEventListener;
 import org.opendaylight.netconf.shaded.sshd.common.io.IoServiceFactory;
 import org.opendaylight.netconf.shaded.sshd.common.io.IoServiceFactoryFactory;
-import org.opendaylight.netconf.shaded.sshd.common.io.nio2.Nio2Acceptor;
-import org.opendaylight.netconf.shaded.sshd.common.io.nio2.Nio2Connector;
+import org.opendaylight.netconf.shaded.sshd.common.io.nio2.Nio2ServiceFactory;
 import org.opendaylight.netconf.shaded.sshd.common.io.nio2.Nio2ServiceFactoryFactory;
 import org.opendaylight.netconf.shaded.sshd.common.session.SessionHeartbeatController.HeartbeatType;
 import org.opendaylight.netconf.shaded.sshd.common.util.closeable.AbstractCloseable;
+import org.opendaylight.netconf.shaded.sshd.common.util.threads.NoCloseExecutor;
 import org.opendaylight.netconf.shaded.sshd.core.CoreModuleProperties;
 import org.opendaylight.netconf.shaded.sshd.server.SshServer;
 
@@ -127,16 +127,16 @@ public void close() throws IOException {
  }
 
  private abstract static class AbstractNioServiceFactory extends AbstractCloseable implements IoServiceFactory {
- private final FactoryManager manager;
  private final AsynchronousChannelGroup group;
  private final ExecutorService resumeTasks;
+ private final Nio2ServiceFactory serviceFactory;
  private IoServiceEventListener eventListener;
 
  AbstractNioServiceFactory(final FactoryManager manager, final AsynchronousChannelGroup group,
  final ExecutorService resumeTasks) {
- this.manager = requireNonNull(manager);
  this.group = requireNonNull(group);
  this.resumeTasks = requireNonNull(resumeTasks);
+ serviceFactory = new Nio2ServiceFactory(manager, null, new NoCloseExecutor(resumeTasks));
  }
 
  final AsynchronousChannelGroup group() {
@@ -149,12 +149,12 @@ final ExecutorService resumeTasks() {
 
  @Override
  public final IoConnector createConnector(final IoHandler handler) {
- return new Nio2Connector(manager, handler, group, resumeTasks);
+ return serviceFactory.createConnector(handler);
  }
 
  @Override
  public final IoAcceptor createAcceptor(final IoHandler handler) {
- return new Nio2Acceptor(manager, handler, group, resumeTasks);
+ return serviceFactory.createAcceptor(handler);
  }
 
  @Override