ikr.simlib.messages

Class Message

java.lang.Object

ikr.simlib.messages.Message

Direct Known Subclasses:

IPPacket, LabelMessage

public class Message
extends java.lang.Object

The center of the simulation is the exchange of messages (that represent data packets) between individual model components.
All messages are derived from the class Message and therefore inherit the following characteristics:

- A so-called message type is defined upon constructor call as a 32-bit word and can be retrieved with getMessageType().

- Messages have a length which is set to one by default. This length can be set by the method setLength(long) and retrieved by getLength().

- Messages can contain several time stamps of the type TimeStamp for the purpose of transfer time measurements. They can be managed with the functions addTimeStamp(), getTimeStamp() and removeTimeStamps(). This is especially important when dealing with time measurements.

- Message contains several output functions (#printMessage(PrintWriter), #printHeader(PrintWriter), #printContent(PrintWriter)) that can be overridden if needed.
Creating messages usually takes place in a generator (Generator). Generally a generator contains an element of the class MessageFactory, which copies a given default message on to the heap with the help of the copy constructor (can be overwritten). By using the port concept, a message is passed from one model component to the next, whereby a reference to each message is additionally passed on during the process of the handshake protocol between two components. Messages are usually deleted in so-called sinks (Sink).

Special Message Types

Within an individual model, it might be necessary to have a message with special members. LabelMessage and IPPacket are two implemented examples. LabelMessage has one additional label whereas IPPacket includes the most important fields of the IP header like source and destination id, a group and type field as well as a member for a tag usually used for scheduling. Special Methods to access and set these fields start with get<*>() and set<*>().

The length field of a message does not have to be used (initialized) as the default length is DEFAULT_MESSAGE_LENGTH (1).

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_MESSAGE_LENGTH

Constructor Summary

Constructors

Constructor and Description
Message()
Message(long length)

Method Summary

Methods

Modifier and Type	Method and Description
long	getLength()
void	setLength(long length)
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_MESSAGE_LENGTH

public static final int DEFAULT_MESSAGE_LENGTH

See Also:

Constant Field Values

Constructor Detail

Message

public Message(long length)

Message

public Message()

Method Detail

getLength

public long getLength()

setLength

public void setLength(long length)

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object