com.connecterra.ale.reader
Class ByteStreamDeviceChannel

java.lang.Object
  com.connecterra.ale.reader.DeviceChannel
      com.connecterra.ale.reader.SocketDeviceChannel
          com.connecterra.ale.reader.ByteStreamDeviceChannel

public class ByteStreamDeviceChannel
extends com.connecterra.ale.reader.SocketDeviceChannel

A DeviceChannel implemented by a TCP connection initiated by the device driver. It extends the SocketDeviceChannel to provide buffering on the input and output streams.

Nested Class Summary

Nested classes/interfaces inherited from class com.connecterra.ale.reader.SocketDeviceChannel

com.connecterra.ale.reader.SocketDeviceChannel.BlockingSocketInputListener, com.connecterra.ale.reader.SocketDeviceChannel.SocketInputListener

Nested classes/interfaces inherited from class com.connecterra.ale.reader.DeviceChannel

DeviceChannel.AbstractOpenChannel, DeviceChannel.MarkingInputStream

Constructor Summary

ByteStreamDeviceChannel(PluginConfig rc, String portName)
Creates a new ByteStreamDeviceChannel instance where the remote host is read from the hostname parameter and the remote port is read from the parameter named by the portName argument in the given PluginConfig.

Method Summary

BufferedInputStream	getInputStream() Returns a BufferedInputStream for reading from an open channel.
BufferedOutputStream	getOutputStream()

Methods inherited from class com.connecterra.ale.reader.SocketDeviceChannel

addDeviceAttributes, addToPluginMeta, addToPluginMeta, close, getHostname, getPort, getSocket, open, ready, setBlockingListener, setListener, toString

Methods inherited from class com.connecterra.ale.reader.DeviceChannel

getLogger, getReactor, markUsed, reactivateChannels

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ByteStreamDeviceChannel

public ByteStreamDeviceChannel(PluginConfig rc,
                               String portName)
                        throws com.connecterra.ale.resources.PluginLoadException

Creates a new ByteStreamDeviceChannel instance where the remote host is read from the hostname parameter and the remote port is read from the parameter named by the portName argument in the given PluginConfig. The timeout for socket operations is read from the socketTimeout parameter in the PluginConfig.

Parameters:

portName - the String key name of the remote port parameter

Throws:

com.connecterra.ale.resources.PluginLoadException - if a configuration error occurs

Method Detail

getInputStream

public BufferedInputStream getInputStream()
                                   throws IOException

Returns a BufferedInputStream for reading from an open channel.

If this method is used by a driver which expects to receive data asynchronously, and this method is used to read a synchronous result from a command, then there is a pitfall to avoid: if the device sent asynchronous data before the synchronous command was received and processed, then the command "response" may actually be the asynchronous data. The reader should be aware of this, and be prepared to handle the asynchronous data, either immediately or by queueing it for later processing.

Overrides:

getInputStream in class com.connecterra.ale.reader.SocketDeviceChannel

Returns:

a BufferedInputStream for reading from an open channel.

Throws:

IOException - if the channel is not open

getOutputStream

public BufferedOutputStream getOutputStream()
                                     throws IOException

Overrides:

getOutputStream in class com.connecterra.ale.reader.SocketDeviceChannel

Returns:

a BufferedOutputStream for writing to an open channel.

Throws:

IOException - if the channel is not open