packetCapturer

Class PacketCapturer

java.lang.Object

packetCapturer.PacketCapturer

All Implemented Interfaces:

java.lang.Runnable

public class PacketCapturer
extends java.lang.Object
implements java.lang.Runnable

The class PacketCapturer is the primary class of the Packet Capturer module.

When it is instantiated it sets up a Capturer for all Ethernet network interfaces. Each Capturer runs in its own thread. It also sets up a queue where all captured packets are stored until they are retrieved by the FlowGenerator.

It is intended to run in its own thread.

Author:

Tomasz Bujlow (tbu@es.aau.dk)

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	isStarted Flag used to determine if the thread is fully started.
private static org.apache.log4j.Logger	log Used to log different events.
private java.util.ArrayList<Capturer>	myCapturers List of capturers for particular network interfaces.
private CapturedPacketsQueue	myPacketsQueue Queue of captured packets.
private java.lang.Thread	packetCapturerThread Thread used by this class.
private boolean	runFlag Flag used to stop the thread.
private java.util.ArrayList<org.jnetpcap.PcapIf>	supportedDevices List of interfaces which we support to capture the traffic on.

Constructor Summary

Constructors

Constructor and Description
PacketCapturer() Constructs the object.

Method Summary

Methods

Modifier and Type	Method and Description
private boolean	addedDevices() Checks if new network interfaces were added to the system.
CapturedPacketsQueue	getCapturedPacketsQueue() Gets queue of captured packets.
private java.util.ArrayList<org.jnetpcap.PcapIf>	getValidDevices() Gets list of supported network devices.
boolean	isAlive() Checks if PacketCapturer is alive.
private boolean	isOK() Checks if all the capturers are functioning properly.
void	run() Runs the thread.
void	start() Starts the thread.
void	stop() Stops the thread.

Methods inherited from class java.lang.Object

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

Field Detail

log

private static org.apache.log4j.Logger log

Used to log different events.

packetCapturerThread

private java.lang.Thread packetCapturerThread

Thread used by this class.

runFlag

private boolean runFlag

Flag used to stop the thread.

isStarted

private boolean isStarted

Flag used to determine if the thread is fully started.

myPacketsQueue

private CapturedPacketsQueue myPacketsQueue

Queue of captured packets.

myCapturers

private java.util.ArrayList<Capturer> myCapturers

List of capturers for particular network interfaces.

supportedDevices

private java.util.ArrayList<org.jnetpcap.PcapIf> supportedDevices

List of interfaces which we support to capture the traffic on.

Constructor Detail

PacketCapturer

public PacketCapturer()

Constructs the object.

Method Detail

start

public void start()

Starts the thread.

stop

public void stop()

Stops the thread. Before stopping the thread itself, stop capturers for all interfaces in the system.

isAlive

public boolean isAlive()

Checks if PacketCapturer is alive. It means that:
- the thread must exists
- the thread must be fully started and running (isStarted equals true). This condition is used to check if the thread is fully started or if it needs more time to start.

Returns:

true if the thread is fully started and operational, false otherwise

run

public void run()

Runs the thread. The logic is following:
- get list of supported network devices and create a capturer for each device
- start capturer for each device
- in loop monitor all the capturers and check them for failures. In case of failure exit the thread, to enforce restart of the VBS client

Specified by:

run in interface java.lang.Runnable

getValidDevices

private java.util.ArrayList<org.jnetpcap.PcapIf> getValidDevices()

Gets list of supported network devices.

Returns:

list of supported network devices

addedDevices

private boolean addedDevices()

Checks if new network interfaces were added to the system.

Returns:

true if new devices were added, false otherwise

isOK

private boolean isOK()

Checks if all the capturers are functioning properly.

Returns:

true if all capturers are functioning properly, false if one or more capturers crashed

getCapturedPacketsQueue

public CapturedPacketsQueue getCapturedPacketsQueue()

Gets queue of captured packets.

Returns:

queue of captured packets.