AX25Stack

java.lang.Object
- org.ka2ddo.ax25.AX25Stack

All Implemented Interfaces:

java.lang.Runnable, FrameListener
```
public class AX25Stack
extends java.lang.Object
implements FrameListener, java.lang.Runnable
```
This class implements the internal AX.25 protocol stack for a TNC (layer 2). It does not implement the level 7 applications or any layer 3 protocols.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addAprsMessageListener(AprsMessageListener listener)` Register an AprsMessageListener to be notified of incoming parsed APRS messages.
`void`	`addAX25FrameListener(AX25FrameListener l)` Add a listener for incoming AX.25 frames.
`void`	`addParsedAX25MessageListener(ParsedAX25MessageListener listener)` Register an ParsedAX25MessageListener to be notified of incoming parsed level 3 protocol messages (other than APRS).
`void`	`consumeFrame(AX25Frame frame)` Queue one AX.25 frame (containing some sort of message) for parsing and processing.
`void`	`consumeFrameNow(Connector connector, AX25Frame frame)` Process an incoming AX,25 frame.
`void`	`fireConsumeAX25Frame(AX25Frame frame, Connector connector)` Send the specified incoming frame to all registered AX25FrameListeners.
`java.util.Map<AX25Callsign,java.util.Map<AX25Callsign,ConnState>>`	`getConnectionMap()` Get the map of all outstanding I-frame connected sessions observed by or end-pointed at this station.
`int`	`getCurrentBacklog()` Return the current number of backlogged frames to be processed by the AX25Stack thread.
`static java.lang.String[]`	`getDigipeaters()` Get the default list of digipeaters for this stack.
`static AX25Stack`	`getInstance()` Get a handle to the AX25Stack singleton.
`int`	`getMaxBacklog()` Return the maximum backlog ever incurred by the AX25Stack parser thread.
`int`	`getMaxQueueCapacity()` Return the maximum allowed size of the queue.
`int`	`getNumConsumedMsgs()` Return the number of AX.25 messages consumed by the AX25Stack.
`AX25Parser`	`getParser(byte pid)` Get the protocol parsing handler for the specified protocol.
`static ConnState.ConnType`	`getStateOf(AX25Callsign src, AX25Callsign dst)` Get the connection state of an I-frame connection session between the specified two callsigns.
`static java.lang.String`	`getToCall()` Get the destination callsign (tocall) that should be used for messages originated by this station.
`boolean`	`isFrozen()` Report if parser thread is frozen.
`static boolean`	`isLocalDest(AX25Callsign dest)` Test if this callsign is addressed to the local station.
`static boolean`	`isLocalDest(java.lang.String destCallsign)` Test if this callsign is addressed to the local station.
`void`	`openConnection(AX25Callsign src, AX25Callsign dest, AX25Callsign[] via, ConnectionEstablishmentListener callback, java.lang.Object sessionIdentifier)` Attempt to initiate an I-frame connected-mode session from the specified source (usually, the local station) to another station by sending a SABM frame.
`void`	`processAPRSPacket(AX25Frame frame, AX25Message aprsMsg)` Send this message (and its associated frame) to the APRS consumers.
`boolean`	`processIBody(AX25Frame frame, boolean isUI, Connector connector, long rcvTimestamp)` This method consumes one information frame.
`void`	`processParsedAX25Message(AX25Frame frame, AX25Message parsedMsg)` Dispatch an AX.25 frame that was parsed into a higher-level protocol to all registered listeners.
`void`	`registerProtocolParser(byte pid, AX25Parser parser)` Register another protocol parsing handler for a particular AX.25 UI/I message PID.
`void`	`removeAprsMessageListener(AprsMessageListener listener)` Unregister an AprsMessageListener to be notified of incoming parsed APRS messages.
`void`	`removeAX25FrameListener(AX25FrameListener l)` Remove a listener for incoming AX.25 frames.
`void`	`removeParsedAX25MessageListener(ParsedAX25MessageListener listener)` Unregister an ParsedAX25MessageListener to be notified of incoming parsed level 3 protocol messages (other than APRS).
`static AX25Callsign[]`	`reverseDigipeaters(AX25Callsign[] srcRelays)` Reverse the order of a sequence of digipeaters (explicit and APRS aliases).
`void`	`run()` Private method to asynchronously consume AX25Frame objects for parsing.
`static void`	`setDigipeaters(java.lang.String[] digipeaters)` Set the default list of digipeaters for this stack.
`void`	`setFrozen(boolean frozen)` Specify whether the AX.25 parser thread should be paused (frozen) to allow the user to view the output without it moving constantly
`static void`	`setToCall(java.lang.String toCall)` Set the destination callsign (tocall) that should be used for messages originated by this station.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - getInstance
```
public static AX25Stack getInstance()
```
    Get a handle to the AX25Stack singleton.
    
    Returns:
    
    AX25Stack instance
  - getDigipeaters
```
public static java.lang.String[] getDigipeaters()
```
    Get the default list of digipeaters for this stack.
    
    Returns:
    
    array of String digipeater aliases supported by this stack
  - setDigipeaters
```
public static void setDigipeaters(java.lang.String[] digipeaters)
```
    Set the default list of digipeaters for this stack.
    
    Parameters:
    
    digipeaters - array of String digipeater aliases
  - getToCall
```
public static java.lang.String getToCall()
```
    Get the destination callsign (tocall) that should be used for messages originated by this station.
    
    Returns:
    
    destination callsign (tocall)
  - setToCall
```
public static void setToCall(java.lang.String toCall)
```
    Set the destination callsign (tocall) that should be used for messages originated by this station.
    
    Parameters:
    
    toCall - destination callsign (tocall)
  - addAX25FrameListener
```
public void addAX25FrameListener(AX25FrameListener l)
```
    Add a listener for incoming AX.25 frames.
    
    Parameters:
    
    l - AX25FrameListener to register
  - removeAX25FrameListener
```
public void removeAX25FrameListener(AX25FrameListener l)
```
    Remove a listener for incoming AX.25 frames.
    
    Parameters:
    
    l - AX25FrameListener to unregister
  - registerProtocolParser
```
public void registerProtocolParser(byte pid,
                                   AX25Parser parser)
```
    Register another protocol parsing handler for a particular AX.25 UI/I message PID.
    
    Parameters:
    
    pid - pid byte code for this protocol
    
    parser - AX25Parser to handle receiving this protocol
  - getParser
```
public AX25Parser getParser(byte pid)
```
    Get the protocol parsing handler for the specified protocol.
    
    Parameters:
    
    pid - level 3 protocol ID byte (as defined by the AX.25 protocol specification)
    
    Returns:
    
    AX25Parser object, or null if no parser registered for the specified protocol
  - fireConsumeAX25Frame
```
public void fireConsumeAX25Frame(AX25Frame frame,
                                 Connector connector)
```
    Send the specified incoming frame to all registered AX25FrameListeners.
    
    Parameters:
    
    frame - AX25Frame to dispatch
    
    connector - Connector that received the frame
  - consumeFrame
```
public void consumeFrame(AX25Frame frame)
```
    Queue one AX.25 frame (containing some sort of message) for parsing and processing.
    
    Specified by:
    
    consumeFrame in interface FrameListener
    
    Parameters:
    
    frame - the AX25Frame to be processed
  - getCurrentBacklog
```
public int getCurrentBacklog()
```
    Return the current number of backlogged frames to be processed by the AX25Stack thread.
    
    Returns:
    
    current queue size
  - getMaxBacklog
```
public int getMaxBacklog()
```
    Return the maximum backlog ever incurred by the AX25Stack parser thread.
    
    Returns:
    
    maximum queue backlog
  - getMaxQueueCapacity
```
public int getMaxQueueCapacity()
```
    Return the maximum allowed size of the queue.
    
    Returns:
    
    total capacity of the backlog queue
  - getNumConsumedMsgs
```
public int getNumConsumedMsgs()
```
    Return the number of AX.25 messages consumed by the AX25Stack.
    
    Returns:
    
    count of messages consumed
  - run
```
public void run()
```
    Private method to asynchronously consume AX25Frame objects for parsing. This tries to prevent back-pressuring any sources (particularly fast-moving TCP connections to APRS-IS servers). Can only be executed from the singleton thread created by this class.
    
    Specified by:
    
    run in interface java.lang.Runnable
  - isFrozen
```
public boolean isFrozen()
```
    Report if parser thread is frozen.
    
    Returns:
    
    boolean true if parser thread is stopped
  - setFrozen
```
public void setFrozen(boolean frozen)
```
    Specify whether the AX.25 parser thread should be paused (frozen) to allow the user to view the output without it moving constantly
    
    Parameters:
    
    frozen - boolean true to freeze the parser thread, or false to resume execution
  - consumeFrameNow
```
public void consumeFrameNow(Connector connector,
                            AX25Frame frame)
```
    Process an incoming AX,25 frame.
    
    Parameters:
    
    connector - Connector that received the frame
    
    frame - AX25Frame to process
  - getConnectionMap
```
public java.util.Map<AX25Callsign,java.util.Map<AX25Callsign,ConnState>> getConnectionMap()
```
    Get the map of all outstanding I-frame connected sessions observed by or end-pointed at this station.
    
    Returns:
    
    Map by initiating callsign of Maps by destination callsign of connection states
  - getStateOf
```
public static ConnState.ConnType getStateOf(AX25Callsign src,
                                            AX25Callsign dst)
```
    Get the connection state of an I-frame connection session between the specified two callsigns.
    
    Parameters:
    
    src - AX25Callsign of originating end of session
    
    dst - AX25Callsign of receiving end of session
    
    Returns:
    
    ConnType of the session, or ConnType.NONE if there is no such connection session known to this protocol stack
  - reverseDigipeaters
```
public static AX25Callsign[] reverseDigipeaters(AX25Callsign[] srcRelays)
```
    Reverse the order of a sequence of digipeaters (explicit and APRS aliases).
    
    Parameters:
    
    srcRelays - array of AX25Callsign indicating the path used to get from sender to recipient
    
    Returns:
    
    array of AX25Callsigns needed to go from recipient back to sender
  - processIBody
```
public boolean processIBody(AX25Frame frame,
                            boolean isUI,
                            Connector connector,
                            long rcvTimestamp)
```
    This method consumes one information frame. The caller handles any flow control issues for I (versus UI) frames.
    
    Parameters:
    
    frame - AX25Frame to be decoded
    
    isUI - where frame was received in a UI AX.25 frame instead of an I frame
    
    connector - PortConnector over which message arrived, or null for file playback
    
    rcvTimestamp - time (in Java-standard milliseconds since Jan 1 1970 UTC) that message was received
    
    Returns:
    
    boolean true if message has already been reported to listeners
  - processParsedAX25Message
```
public void processParsedAX25Message(AX25Frame frame,
                                     AX25Message parsedMsg)
```
    Dispatch an AX.25 frame that was parsed into a higher-level protocol to all registered listeners.
    
    Parameters:
    
    frame - AX25Frame of incoming message
    
    parsedMsg - AX25Message subclass containing protocol decoding of message
  - processAPRSPacket
```
public void processAPRSPacket(AX25Frame frame,
                              AX25Message aprsMsg)
```
    Send this message (and its associated frame) to the APRS consumers.
    
    Parameters:
    
    frame - AX25Frame containing the APRS message
    
    aprsMsg - Message that was sent
  - addAprsMessageListener
```
public void addAprsMessageListener(AprsMessageListener listener)
```
    Register an AprsMessageListener to be notified of incoming parsed APRS messages.
    
    Parameters:
    
    listener - AprsMessageListener to register
  - removeAprsMessageListener
```
public void removeAprsMessageListener(AprsMessageListener listener)
```
    Unregister an AprsMessageListener to be notified of incoming parsed APRS messages.
    
    Parameters:
    
    listener - AprsMessageListener to unregister
  - addParsedAX25MessageListener
```
public void addParsedAX25MessageListener(ParsedAX25MessageListener listener)
```
    Register an ParsedAX25MessageListener to be notified of incoming parsed level 3 protocol messages (other than APRS).
    
    Parameters:
    
    listener - ParsedAX25MessageListener to register
  - removeParsedAX25MessageListener
```
public void removeParsedAX25MessageListener(ParsedAX25MessageListener listener)
```
    Unregister an ParsedAX25MessageListener to be notified of incoming parsed level 3 protocol messages (other than APRS).
    
    Parameters:
    
    listener - ParsedAX25MessageListener to unregister
  - isLocalDest
```
public static boolean isLocalDest(AX25Callsign dest)
```
    Test if this callsign is addressed to the local station.
    
    Parameters:
    
    dest - AX25Callsign to test as a destination
    
    Returns:
    
    boolean true if this callsign is for the local station
  - isLocalDest
```
public static boolean isLocalDest(java.lang.String destCallsign)
```
    Test if this callsign is addressed to the local station.
    
    Parameters:
    
    destCallsign - String of AX.25 callsign-SSID to test as a destination
    
    Returns:
    
    boolean true if this callsign is for the local station
  - openConnection
```
public void openConnection(AX25Callsign src,
                           AX25Callsign dest,
                           AX25Callsign[] via,
                           ConnectionEstablishmentListener callback,
                           java.lang.Object sessionIdentifier)
                    throws java.io.IOException
```
    Attempt to initiate an I-frame connected-mode session from the specified source (usually, the local station) to another station by sending a SABM frame.
    
    Parameters:
    
    src - AX25Callsign of originating station
    
    dest - AX25Callsign of destination for connection
    
    via - digipeater path (may be null)
    
    callback - ConnectionEstablishmentListener to be notified of changes in state of the connection
    
    sessionIdentifier - arbitrary unique identifier for the connection, so that the ConnectionEstablishmentListener can tell which connection is being reported about
    
    Throws:
    
    java.io.IOException - if connection initiation (SABM frame) could not be sent

Class AX25Stack

Method Summary

Methods inherited from class java.lang.Object

Method Detail

getInstance

getDigipeaters

setDigipeaters

getToCall

setToCall

addAX25FrameListener

removeAX25FrameListener

registerProtocolParser

getParser

fireConsumeAX25Frame

consumeFrame

getCurrentBacklog

getMaxBacklog

getMaxQueueCapacity

getNumConsumedMsgs

run

isFrozen

setFrozen

consumeFrameNow

getConnectionMap

getStateOf

reverseDigipeaters

processIBody

processParsedAX25Message

processAPRSPacket

addAprsMessageListener

removeAprsMessageListener

addParsedAX25MessageListener

removeParsedAX25MessageListener

isLocalDest

isLocalDest

openConnection