mil.navy.nps.dis
Class BehaviorStreamBufferTCP

java.lang.Object
  mil.navy.nps.dis.BehaviorStreamBuffer
      mil.navy.nps.dis.BehaviorStreamBufferTCP

All Implemented Interfaces:

AllPermissionsBadge, java.lang.Runnable

public abstract class BehaviorStreamBufferTCP

extends BehaviorStreamBuffer

implements java.lang.Runnable, AllPermissionsBadge

BehaviorStreamBufferTCP is a class responsible for interpreting data received via a TCP socket and interpreting it as DIS PDUs.

DIS is by nature packet-oriented, while TCP is stream-oriented. this means that we must parse the data as it comes in, to determine how many bytes to read. This can be done via the PDU length field in the PDU header. This is always at the same point in the packet, and describes how many bytes to read. By nature, if this count is off, the stream will get scrambled.

Author:

DMcG

Field Summary

static boolean	DEBUG
static int	MAX_DATAGRAM_SIZE
protected SecurityStrategy	strategy SecurityStrategy is used as a way to get around the java sandbox.

Fields inherited from class mil.navy.nps.dis.BehaviorStreamBuffer

info, inputThreadStarted, readThreadRunning, rtpEnabled, runContinue

Constructor Summary

BehaviorStreamBufferTCP(java.net.Socket pSocket)
Constructor, takes a connected socket.

BehaviorStreamBufferTCP(java.lang.String pAddress, int port)
Constructor; takes a string inet address and a port number.

Method Summary

void	cleanup() Closes down input buffers, sockets, or open files nicely
void	debug(java.lang.String pMessage) Debugging output
protected void	finalize() Finalize method--used to clean up any sockets that are still open
ProtocolDataUnit	getNextPdu() Get the next PDU from the input stream.
java.util.Vector	receivedPdus() Returns a vector of all the PDUs received since the last time we asked.
void	resumeReading() Start reading packets from the datagramStreamBuffer again.
void	run() Threading method to read/write until shutdown.
void	sendPdu(ProtocolDataUnit pPdu) Sends a PDU.
void	sendPdu(ProtocolDataUnit pPdu, java.lang.Object pAddress1, java.lang.Object pAddress2) Send a PDU to an address.
void	shutdown() Terminate the run loop and shutdown the thread.
void	startInputThread() Simple method to launch thread.
void	suspendReading() suspend reading in the DatagramStreamBuffer
void	trace(java.lang.String pMessage) tracing output

Methods inherited from class mil.navy.nps.dis.BehaviorStreamBuffer

checkForThreadStart, getDEBUG, getInfo, getRtpEnabled, sendPdu, setDEBUG, setInfo, setRtpEnabled, startInputThreadWithSecurity

Methods inherited from class java.lang.Object

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

Field Detail

MAX_DATAGRAM_SIZE

public static final int MAX_DATAGRAM_SIZE

See Also:

Constant Field Values

DEBUG

public static boolean DEBUG

strategy

protected SecurityStrategy strategy

SecurityStrategy is used as a way to get around the java sandbox. A security scheme is picked at runtime for whatever type of box we are running on.

Constructor Detail

BehaviorStreamBufferTCP

public BehaviorStreamBufferTCP(java.net.Socket pSocket)

Constructor, takes a connected socket. Also starts up a listening thread on this socket.

BehaviorStreamBufferTCP

public BehaviorStreamBufferTCP(java.lang.String pAddress,
                               int port)

Constructor; takes a string inet address and a port number. Establishes a connection to this server and uses that connection for communications. This also starts up a thread for communications with that server.

Method Detail

startInputThread

public void startInputThread()

Simple method to launch thread. This kicks of the BSBTCP and starts it reading in its own thread. This is required for some subclasses of BSB, such as sockets; for files, this is optional-- we can read one PDU at a time from them without blocking.

Specified by:

startInputThread in class BehaviorStreamBuffer

shutdown

public void shutdown()

Terminate the run loop and shutdown the thread. This should be used only for threaded readers.

Specified by:

shutdown in class BehaviorStreamBuffer

suspendReading

public void suspendReading()

suspend reading in the DatagramStreamBuffer

Specified by:

suspendReading in class BehaviorStreamBuffer

resumeReading

public void resumeReading()

Start reading packets from the datagramStreamBuffer again.

Specified by:

resumeReading in class BehaviorStreamBuffer

run

public void run()

Threading method to read/write until shutdown.

Specified by:

run in interface java.lang.Runnable

Specified by:

run in class BehaviorStreamBuffer

receivedPdus

public java.util.Vector receivedPdus()

Returns a vector of all the PDUs received since the last time we asked. Queries the underlying input buffer for this information.\ this is generally used with threaded readers.

Specified by:

receivedPdus in class BehaviorStreamBuffer

getNextPdu

public ProtocolDataUnit getNextPdu()

Get the next PDU from the input stream. This is generally used with unthreaded readers.

Specified by:

getNextPdu in class BehaviorStreamBuffer

sendPdu

public void sendPdu(ProtocolDataUnit pPdu)

Sends a PDU. If the underlying destination address has already been set, for example in a multicast or file, we don't need to supply an address.

Specified by:

sendPdu in class BehaviorStreamBuffer

sendPdu

public void sendPdu(ProtocolDataUnit pPdu,
                    java.lang.Object pAddress1,
                    java.lang.Object pAddress2)

Send a PDU to an address. Since the address can be in many forms, for example an InetAddress and a port number, we cheat here. The destination address is passed in as generic objects; a concrete subclass, such as a Unicast UDP object, will cast the generic objects here to what it expects, such as an InetAddress. (After checking for the right type with instanceof, of course!)

Note that if you're sending to the "standard" tcp destination address, you should use sendPdu().

Specified by:

sendPdu in class BehaviorStreamBuffer

Parameters:

pPdu - protocol data unit being sent

pAddress1 - TCP address of destination

pAddress2 - port of destination

cleanup

public void cleanup()

Closes down input buffers, sockets, or open files nicely

Specified by:

cleanup in class BehaviorStreamBuffer

finalize

protected void finalize()
                 throws java.lang.Throwable

Finalize method--used to clean up any sockets that are still open

Specified by:

finalize in class BehaviorStreamBuffer

Throws:

java.lang.Throwable

trace

public void trace(java.lang.String pMessage)

tracing output

Overrides:

trace in class BehaviorStreamBuffer

debug

public void debug(java.lang.String pMessage)

Debugging output

Overrides:

debug in class BehaviorStreamBuffer