de.htw.berlin.polysun4diac.forte.comm

Class AbstractCommunicationLayer

java.lang.Object

de.htw.berlin.polysun4diac.forte.comm.AbstractCommunicationLayer

All Implemented Interfaces:

ICommunicationLayer, java.io.Serializable

Direct Known Subclasses:

de.htw.berlin.polysun4diac.forte.comm.AbstractDataBufferLayer, CommFunctionBlockLayer, IPcommunicationLayer, TCPcommunicationLayer, UDPcommunicationLayer

public abstract class AbstractCommunicationLayer
extends java.lang.Object
implements java.io.Serializable, ICommunicationLayer

Abstract class providing the default implementation of an OSI layer. Loosely based on the OSI layer interface implemented in FORTE.

Author:

Marc Jakobi

HTW Berlin

July 2017

See Also:

FORTE communication architecture, Serialized Form

Constructor Summary

Constructors

Constructor and Description
AbstractCommunicationLayer()

Method Summary

Modifier and Type	Method and Description
boolean	closeConnection() Closes this layer and calls closeConnection() on the layer below.
ICommunicationLayer	getAbove()
ICommunicationLayer	getBelow()
boolean	getConnectionState()
byte[]	getRawBytes()
boolean	openConnection(CommLayerParams params) Opens the connection and sets up the communication stack.
byte	readByte() Reads a byte from the communication layer below or the connected device if this layer is the bottom layer.
double	readDouble() Reads 8 bytes from the communication layer below or the connected device if this layer is the bottom layer.
float	readFloat() Reads 4 bytes from the communication layer below or the connected device if this layer is the bottom layer.
long	readLong() Reads 4 bytes from the communication layer below or the connected device if this layer is the bottom layer.
void	recvData() Performs the necessary actions for receiving data.
void	sendData(byte[] data) Performs the necessary actions for sending data.
void	sendData(byte[] data, int off, int len) Performs the necessary actions for sending data.
void	setAbove(ICommunicationLayer layer) Sets the communication layer above this layer.
void	setBelow(ICommunicationLayer layer) Sets the communication layer below this layer.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AbstractCommunicationLayer

public AbstractCommunicationLayer()

Method Detail

openConnection

public boolean openConnection(CommLayerParams params)
                       throws java.io.IOException

Description copied from interface: ICommunicationLayer

Opens the connection and sets up the communication stack. If necessary, additional layers below this layer are created.

Specified by:

openConnection in interface ICommunicationLayer

Parameters:

params - CommLayerParams object holding the connection info

Returns:

true if the connection was opened successfully, false otherwise

Throws:

java.io.IOException

closeConnection

public boolean closeConnection()
                        throws java.io.IOException

Description copied from interface: ICommunicationLayer

Closes this layer and calls closeConnection() on the layer below.

Specified by:

closeConnection in interface ICommunicationLayer

Returns:

true if the connection was closed successfully, false otherwise

Throws:

java.io.IOException

sendData

public void sendData(byte[] data,
                     int off,
                     int len)
              throws java.io.IOException

Description copied from interface: ICommunicationLayer

Performs the necessary actions for sending data.

Specified by:

sendData in interface ICommunicationLayer

Parameters:

data - Byte array containing the data

len - Length of the data to be sent

Throws:

java.io.IOException

sendData

public void sendData(byte[] data)
              throws java.io.IOException

Description copied from interface: ICommunicationLayer

Performs the necessary actions for sending data. Equivalent to calling sendData(data, 0, data.length);

Specified by:

sendData in interface ICommunicationLayer

Parameters:

data - Byte array containing the data

Throws:

java.io.IOException

recvData

public void recvData()
              throws java.io.IOException

Description copied from interface: ICommunicationLayer

Performs the necessary actions for receiving data.

Specified by:

recvData in interface ICommunicationLayer

Throws:

java.io.IOException

getAbove

public ICommunicationLayer getAbove()

Specified by:

getAbove in interface ICommunicationLayer

Returns:

the communication layer above this layer

getBelow

public ICommunicationLayer getBelow()

Specified by:

getBelow in interface ICommunicationLayer

Returns:

the communication layer below this layer

setAbove

public void setAbove(ICommunicationLayer layer)

Description copied from interface: ICommunicationLayer

Sets the communication layer above this layer.

Specified by:

setAbove in interface ICommunicationLayer

setBelow

public void setBelow(ICommunicationLayer layer)

Description copied from interface: ICommunicationLayer

Sets the communication layer below this layer.

Specified by:

setBelow in interface ICommunicationLayer

readByte

public byte readByte()
              throws java.io.IOException

Description copied from interface: ICommunicationLayer

Reads a byte from the communication layer below or the connected device if this layer is the bottom layer.

Specified by:

readByte in interface ICommunicationLayer

Throws:

java.io.IOException

readLong

public long readLong()
              throws java.io.IOException

Description copied from interface: ICommunicationLayer

Reads 4 bytes from the communication layer below or the connected device if this layer is the bottom layer.

Specified by:

readLong in interface ICommunicationLayer

Returns:

the long value represented by the 4 bytes.

Throws:

java.io.IOException

readDouble

public double readDouble()
                  throws java.io.IOException

Description copied from interface: ICommunicationLayer

Reads 8 bytes from the communication layer below or the connected device if this layer is the bottom layer.

Specified by:

readDouble in interface ICommunicationLayer

Returns:

the double value represented by the 8 bytes.

Throws:

java.io.IOException

readFloat

public float readFloat()
                throws java.io.IOException

Description copied from interface: ICommunicationLayer

Reads 4 bytes from the communication layer below or the connected device if this layer is the bottom layer.

Specified by:

readFloat in interface ICommunicationLayer

Returns:

the float value represented by the 4 bytes.

Throws:

java.io.IOException

getConnectionState

public boolean getConnectionState()

Specified by:

getConnectionState in interface ICommunicationLayer

Returns:

true if the layer is connected, false otherwise.

getRawBytes

public byte[] getRawBytes()

Specified by:

getRawBytes in interface ICommunicationLayer

Returns:

a byte array holding the raw data retrieved by calling ICommunicationLayer.recvData()