### Question:
PlainMailboxManager implements MailboxManager { public Object transportQuery( Object query ) throws Exception { return transport.transportQuery( query ); } PlainMailboxManager( TransportMessage transport, String uri,
		Resources resources );  PlainMailboxManager( TransportMessage transport, URL uri,
		Resources resources ); TransportMessage getTransport(); @Override String toString(); boolean sessionMessage( Who sender, Message msg ); void transportMessage( Who recipient, Message msg ); Mailbox transportCall( Who recipient, Message msg ); void register( Mailbox mb ); void unregister( Mailbox mb ); Mailbox getMailbox( Long msgid ); void redeliver( Who sender, Message msg ); int size(); Object sessionQuery( Object query ); void sessionControl( Object control, Object value ); void sessionNotify( Object event ); Object transportQuery( Object query ); void transportControl( Object control, Object value ); void transportNotify( Object event ); SessionMessage getSession(); void setSession( SessionMessage session );  }### Answer:
@Test public void transportQuery() throws Exception { Object QUERY = "foo"; Object RESULT = "bar"; assertNull( transport.what ); assertNull( transport.query ); transport.query_result = RESULT; Object result = mmgr.transportQuery( QUERY ); assertSame( What.TRANSPORT_QUERY, transport.what ); assertSame( QUERY, transport.query ); assertSame( RESULT, result ); }