ConnectionListener (Project Darkstar Shared 1.1 API)

```
public interface ConnectionListener
```
Receives asynchronous notification of events from an associated Connection. The connected method is invoked when the connection is established, either actively from a Connector or passively by an Acceptor. The bytesReceived method is invoked when data arrives on the connection. The exceptionThrown method is invoked to forward asynchronous network exceptions. The disconnected method is invoked when the connection has been closed, or if the connection could not be initiated at all (e.g., when a connector fails to connect).
The IO framework ensures that only one notification is processed at a time for each instance of Connection. Thus, a ConnectionListener does not need to take special steps to ensure thread safety so long as it does not access resources shared among the listeners of other connections.

Methods
Modifier and Type	Method and Description
`void`	`bytesReceived(Connection conn, byte[] message)` Notifies this listener that data arrives on a connection.
`void`	`connected(Connection conn)` Notifies this listener that the connection is established, either actively from a `Connector` or passively by an `Acceptor`.
`void`	`disconnected(Connection conn)` Notifies this listener that the connection has been closed, or that it could not be initiated (e.g., when a `Connector` fails to connect).
`void`	`exceptionThrown(Connection conn, Throwable exception)` Notifies this listener that a network exception has occurred on the connection.

Interface ConnectionListener