请参阅: 说明
| 类 | 说明 | 
|---|---|
| Main | 
 (Entry point) An 'in-VM pipe' example which simulates a tennis game
 between client and server. 
 | 
| TennisBall | 
 A tennis ball which has TTL value and state whose value is one of 'PING' and
 'PONG'. 
 | 
| TennisPlayer | 
 A  
IoHandler implementation which plays a tennis game. |