org.jmythapi.protocol.impl
Class BackendConnection

java.lang.Object
  org.jmythapi.protocol.impl.BackendConnection

All Implemented Interfaces:

Closeable, IVersionable, IBackendConnection

public class BackendConnection
extends Object
implements IVersionable, Closeable, IBackendConnection

Field Summary

Fields inherited from interface org.jmythapi.protocol.IBackendConnection

DEFAULT_COMMAND_PORT

Constructor Summary

BackendConnection(String hostname)

BackendConnection(String hostname, int port)

Method Summary

void	addEventListener(IMythEventPacketListener listener) Registers a new event listener.
boolean	canReadData() Checks if data is available to read without blocking.
boolean	canReadPacket() Checks if at least PacketUtils.SIZE_STRING_LENGTH bytes can be read from the underlying input stream without blocking.
void	close() Closes the connection to the MythTV-backend.
void	enableEventListening() Enables event listening.
int	getConnectTimeout()
String	getHostname() Gets the host name of the backend.
int	getPort() Gets the port of the backend.
int	getReadTimeout()
ProtocolVersion	getVersionNr() Gets the protocol-version of an object.
boolean	isAnnotated()
boolean	isClosed() Gets the curernt connection state.
boolean	isOpen()
protected boolean	negotiate()
void	open() Opens the connection.
void	open(int streamBufferSize, boolean tcpNoDelay) Opens the connection.
int	readData(byte[] b, int offset, int len) Reads bytes from the socket.
IMythPacket	readPacket() Receives the next packet from the backend.
protected IMythPacket	readPacketFromQueue()
protected IMythPacket	readPacketFromSocket()
void	removeEventListener(IMythEventPacketListener listener) Unregisters an event listener.
void	setConnectTimeout(int connectTimeout)
void	setInitialVersionNr(ProtocolVersion initialProtoVersion) Sets the initla protocol-version to use.
void	setMsgDebugOut(PrintStream out) Sets a print stream used to log packets.
void	setReadTimeout(int readTimeout)
String	toString()
void	writeMessage(IMythRequest msg) Sends a request-message to the backend.
void	writePacket(IMythPacket packet) Sends a packet to the backend.

Methods inherited from class java.lang.Object

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

Constructor Detail

BackendConnection

public BackendConnection(String hostname)

BackendConnection

public BackendConnection(String hostname,
                         int port)

Method Detail

setInitialVersionNr

public void setInitialVersionNr(ProtocolVersion initialProtoVersion)
                         throws IllegalStateException

Description copied from interface: IBackendConnection

Sets the initla protocol-version to use.

This function sets the initial protocol-version that will be used by the connection during version negotiation in the course of IBackendConnection.open().

This is mainly usefull to speedup connection establishing.

Specified by:

setInitialVersionNr in interface IBackendConnection

Parameters:

initialProtoVersion - the initial protocol version.

Throws:

IllegalStateException - if the connection is already opened.

getConnectTimeout

public int getConnectTimeout()

Specified by:

getConnectTimeout in interface IBackendConnection

setConnectTimeout

public void setConnectTimeout(int connectTimeout)

Specified by:

setConnectTimeout in interface IBackendConnection

getReadTimeout

public int getReadTimeout()

Specified by:

getReadTimeout in interface IBackendConnection

setReadTimeout

public void setReadTimeout(int readTimeout)

Specified by:

setReadTimeout in interface IBackendConnection

setMsgDebugOut

public void setMsgDebugOut(PrintStream out)

Description copied from interface: IBackendConnection

Sets a print stream used to log packets.

This method sets a print-stream that is used to log incoming and outgoing packets.
This is mainly used for debugging.

Usage example

Printing the packets to std-out.

    backendConnection.setMsgDebugOut(System.out);
  

Due to the above statement the following will be printed to std-out, e.g.

Specified by:

setMsgDebugOut in interface IBackendConnection

Parameters:

out - a print-stream to log messages.

getHostname

public String getHostname()

Description copied from interface: IBackendConnection

Gets the host name of the backend.

Specified by:

getHostname in interface IBackendConnection

Returns:

the host name of the backend.

getPort

public int getPort()

Description copied from interface: IBackendConnection

Gets the port of the backend.

Specified by:

getPort in interface IBackendConnection

Returns:

the port of the backend.

getVersionNr

public ProtocolVersion getVersionNr()

Description copied from interface: IVersionable

Gets the protocol-version of an object.

Specified by:

getVersionNr in interface IVersionable

Returns:

the version a given object was created for.

open

public void open()
          throws IOException

Description copied from interface: IBackendConnection

Opens the connection.

This function opens the connection to the MythTV-backend and negotiates the protocol version to use.

Specified by:

open in interface IBackendConnection

Throws:

IOException - on communication errors.

open

public void open(int streamBufferSize,
                 boolean tcpNoDelay)
          throws IOException

Description copied from interface: IBackendConnection

Opens the connection.

This function opens the connection to the MythTV-backend and negotiates the protocol version to use.

Specified by:

open in interface IBackendConnection

Parameters:

streamBufferSize - the stream buffer size to use

Throws:

IOException - on communication errors

close

public void close()

Description copied from interface: IBackendConnection

Closes the connection to the MythTV-backend.

Specified by:

close in interface Closeable

Specified by:

close in interface IBackendConnection

isClosed

public boolean isClosed()

Description copied from interface: IBackendConnection

Gets the curernt connection state.

Specified by:

isClosed in interface IBackendConnection

Returns:

true if the connection was not established so far or is already closed.

isOpen

public boolean isOpen()

isAnnotated

public boolean isAnnotated()

negotiate

protected boolean negotiate()
                     throws IOException

Throws:

IOException

readPacket

public IMythPacket readPacket()
                       throws IOException

Description copied from interface: IBackendConnection

Receives the next packet from the backend.

Specified by:

readPacket in interface IBackendConnection

Returns:

the next read packet.

Throws:

IOException - on communication errors.

readPacketFromQueue

protected IMythPacket readPacketFromQueue()
                                   throws IOException

Throws:

IOException

readPacketFromSocket

protected IMythPacket readPacketFromSocket()
                                    throws IOException

Throws:

IOException

canReadPacket

public boolean canReadPacket()
                      throws IOException

Description copied from interface: IBackendConnection

Checks if at least PacketUtils.SIZE_STRING_LENGTH bytes can be read from the underlying input stream without blocking.

This function can be used to check if we should start reading the next packet.

Specified by:

canReadPacket in interface IBackendConnection

Returns:

true if the next packet can be read

Throws:

IOException - on communication errors

writePacket

public void writePacket(IMythPacket packet)
                 throws IOException

Description copied from interface: IBackendConnection

Sends a packet to the backend.

Specified by:

writePacket in interface IBackendConnection

Parameters:

packet - to packet to transfer

Throws:

IOException - on communication errors.

writeMessage

public void writeMessage(IMythRequest msg)
                  throws IOException

Description copied from interface: IBackendConnection

Sends a request-message to the backend.

Specified by:

writeMessage in interface IBackendConnection

Parameters:

msg - the request message to be send

Throws:

IOException - on communication errors

UnknownCommandException - if the given command is unknown

UnsupportedCommandException - if the given command is not supported by the given protocol version

readData

public int readData(byte[] b,
                    int offset,
                    int len)
             throws IOException

Description copied from interface: IBackendConnection

Reads bytes from the socket.

Specified by:

readData in interface IBackendConnection

Parameters:

b - the byte array to fill with data

offset - to offset used to start writing into the array

len - the amount of bytes to read

Returns:

the amount of read bytes.

Throws:

IOException - on communication errors

canReadData

public boolean canReadData()
                    throws IOException

Description copied from interface: IBackendConnection

Checks if data is available to read without blocking.

Specified by:

canReadData in interface IBackendConnection

Returns:

true if at least one byte is available to read without blocking.

Throws:

IOException - on communication errors

enableEventListening

public void enableEventListening()

Description copied from interface: IBackendConnection

Enables event listening.

This function starts a new thread, which reads incoming IMythPacket and passes them to event listeners, if the received packets are event packets.

Specified by:

enableEventListening in interface IBackendConnection

addEventListener

public void addEventListener(IMythEventPacketListener listener)

Description copied from interface: IBackendConnection

Registers a new event listener.

Specified by:

addEventListener in interface IBackendConnection

Parameters:

listener - the listener to register

removeEventListener

public void removeEventListener(IMythEventPacketListener listener)

Description copied from interface: IBackendConnection

Unregisters an event listener.

Specified by:

removeEventListener in interface IBackendConnection

Parameters:

listener - the listener to unregister.

toString

public String toString()

Overrides:

toString in class Object