jas.engine
Class Sim

java.lang.Object
  jas.engine.Sim

public class Sim
extends java.lang.Object

Sim is a top-level class keeping static references to engine and other system things. From every point of your code you can access the Sim object and obtain some useful services. This class ensures that only one engine is running on the current JVM. Each model will be attached to the same engine.

Title: JAS

Description: Java Agent-based Simulation library

Copyright (C) 2002 Michele Sonnessa

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.

Author:

Michele Sonnessa

Changes (from ) --------------------------

Field Summary

static java.lang.String[]	cmdLineArguments
static int	currentRunNumber In a multi run model this variable is used to identify the current run number.
static SimEngine	engine Reference to the engine running on the current JVM.
static int	EVENT_SHUTDOWN Event descriptor for application quit.
static int	EVENT_SIMULATION_END Event descriptor for engine stop.
static int	EVENT_SIMULATION_RESTART Event descriptor for engine restart.
static int	EVENT_STEP Generic step event used by simple agents.
static int	EVENT_UPDATE Update event for each updatable object.
static java.lang.String	jasProjectsPath Represents the standard root folder where JAS search for user's projects.
static short	majorVersion The current major version of simulation engine.
static short	minorVersion The current minor version of simulation engine.
static java.lang.String	version The description of the current version.

Constructor Summary

Sim()

Method Summary

static void	addDirectoryToClassLoader(java.io.File directory) Insert the specified directory to the local classpath of the SimClassLoader.
static void	editCode(java.lang.String filePath) Open the file with the default editor.
static void	fatalError(java.lang.Object source, java.lang.String errorDescription) This method should be called when a fatal event occurs, such that the simulation cannot be continued.
static long	getAbsoluteTime() Returns the current absolute simulation time.
static java.lang.String	getCurrentDirectoryPath() Return the current user directory path.
static java.lang.String	getEditorPath() Return the external path for the current code editor.
static EventList	getEventList() Return a reference to the current event list of the simulation engine.
ISimModel	getModelWithID(java.lang.String id) Returns a reference of a SimModel with the given id.
SimMultiCastEvent	getMultiCastService(java.lang.String multiCastService) Return the multicast information service with the given name.
static java.lang.String	getPathOf(java.lang.Object targetObject) Return the current path for the given object.
static RandomGenerator	getRnd() Return a reference to the Sim random number generator.
static DynamicClassLoader	getSimClassLoader() Returns the simulation class loader.
static SimulationServer	getSimulationServer() Return the current simulation server.
static java.lang.String	getStartDirectory() Return the directory from where JVM was started.
static SimTime	getTime() Return the SimTime object used by engine.
static void	main(java.lang.String[] args) The main method starts an engine and show the Control Panel.
static ProbeFrame	openProbe(java.lang.Object on, java.lang.String title) Opens a probe on the given object and return its reference.
static ProbeFrame	openProbe(java.lang.Object on, java.lang.String title, ISimModel ownerModel) Opens a probe on the given object and return its reference.
static void	setCurrentClassLoader(DynamicClassLoader loader) Set a new SimClassLoader.
static void	setCurrentDirectoryPath(java.lang.String newPath) Set the current user directory path.
static void	setEditorPath(java.lang.String editorPath) Set the external path for the code editor.
static void	setEngine(SimEngine eng) Set the current simulation engine.
static void	showMessage(java.lang.String message) Show a system message box with the given message.
static void	shutdownSimulationServer() Shutdown and destroy the simulation server.
static void	startSimulationServer() Create an instance of a SimulationServer and start the service.
static void	startSimulationServer(int onTcpPort) Create an instance of a SimulationServer and start the service.
static long	toDays(int value) Converts the given days to the absolute time value.
static long	toHours(int value) Converts the given hours to the absolute time value.
static long	toMillis(int value) Converts the given milliseconds to the absolute time value.
static long	toMins(int value) Converts the given minutes to the absolute time value.
static long	toMonths(int value) Converts the given months to the absolute time value.
static long	toSecs(int value) Converts the given seconds to the absolute time value.
static long	toYears(int value) Converts the given years to the absolute time value.

Methods inherited from class java.lang.Object

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

Field Detail

cmdLineArguments

public static java.lang.String[] cmdLineArguments

currentRunNumber

public static int currentRunNumber

In a multi run model this variable is used to identify the current run number. Every time the simulation is restarted it is incremented.

engine

public static SimEngine engine

Reference to the engine running on the current JVM.

EVENT_SHUTDOWN

public static final int EVENT_SHUTDOWN

Event descriptor for application quit.

See Also:

Constant Field Values

EVENT_SIMULATION_END

public static final int EVENT_SIMULATION_END

Event descriptor for engine stop.

See Also:

Constant Field Values

EVENT_SIMULATION_RESTART

public static final int EVENT_SIMULATION_RESTART

Event descriptor for engine restart.

See Also:

Constant Field Values

EVENT_STEP

public static final int EVENT_STEP

Generic step event used by simple agents.

See Also:

Constant Field Values

EVENT_UPDATE

public static final int EVENT_UPDATE

Update event for each updatable object.

See Also:

Constant Field Values

jasProjectsPath

public static java.lang.String jasProjectsPath

Represents the standard root folder where JAS search for user's projects.

majorVersion

public static final short majorVersion

The current major version of simulation engine.

See Also:

Constant Field Values

minorVersion

public static final short minorVersion

The current minor version of simulation engine.

See Also:

Constant Field Values

version

public static final java.lang.String version

The description of the current version.

See Also:

Constant Field Values

Constructor Detail

Sim

public Sim()

Method Detail

addDirectoryToClassLoader

public static void addDirectoryToClassLoader(java.io.File directory)

Insert the specified directory to the local classpath of the SimClassLoader. If the engine is currently using the System class loader this method will be ignored.

Parameters:

directory - The directory or jar file to be added.

editCode

public static void editCode(java.lang.String filePath)

Open the file with the default editor. If no editor has been set the command is ignored.

Parameters:

filePath - A fully qualified path to a source code file.

fatalError

public static void fatalError(java.lang.Object source,
                              java.lang.String errorDescription)

This method should be called when a fatal event occurs, such that the simulation cannot be continued. When invoked, this method disposes the models and shows an alert message box.

Parameters:

source - The object generated the error.*

errorDescription - A short error description.

getAbsoluteTime

public static long getAbsoluteTime()

Returns the current absolute simulation time.

Returns:

The absolute time.

getCurrentDirectoryPath

public static java.lang.String getCurrentDirectoryPath()

Return the current user directory path.

Returns:

The string representing the current path.

getEditorPath

public static java.lang.String getEditorPath()

Return the external path for the current code editor.

Returns:

The path of the external editor application.

getEventList

public static EventList getEventList()

Return a reference to the current event list of the simulation engine.

Returns:

The event list used by current engine.

getModelWithID

public ISimModel getModelWithID(java.lang.String id)

Returns a reference of a SimModel with the given id. If the model is not present into the engine running models it returns null.

Parameters:

id - The string describing the SimModel. It must be equal to the returning String of the SimModel.getID() method.

Returns:

The asked model.

getMultiCastService

public SimMultiCastEvent getMultiCastService(java.lang.String multiCastService)

Return the multicast information service with the given name.

getPathOf

public static java.lang.String getPathOf(java.lang.Object targetObject)

Return the current path for the given object. The method looks for the path into the DynamicClassLoader, if file is nof found it is returned the start directory path.

Parameters:

targetObject - A generic object loaded by a simulation model.

Returns:

A path in the format "rootDirectory/subDir/dirWhereTheClassFileIs/".

getRnd

public static RandomGenerator getRnd()

Return a reference to the Sim random number generator. Using this generator you can set the seed number using project parameters. Every simulation can be exactly repeated setting always the same simulation random seed.

Returns:

Reference to the random generator used by the engine.

getSimClassLoader

public static DynamicClassLoader getSimClassLoader()

Returns the simulation class loader. If the Control Panel opens a model from an XML file, the engine create an instance of the DynamicClassLoader. It is able to load classes outside the CLASSPATH, according to the classpath specified in the project file.

Returns:

The current class loader.

getSimulationServer

public static SimulationServer getSimulationServer()

Return the current simulation server.

Returns:

The active simultion server. Null if not yet started.

getStartDirectory

public static java.lang.String getStartDirectory()

Return the directory from where JVM was started.

Returns:

The string representing the start path.

getTime

public static SimTime getTime()

Return the SimTime object used by engine.

Returns:

The current SimTime object.

main

public static void main(java.lang.String[] args)

The main method starts an engine and show the Control Panel. The accepted parameters are:

[-v], [--version] shows the version of the simulation engine.

[-s], [--seed] set the current random seed

Parameters:

args - The command prompt list of arguments.

openProbe

public static ProbeFrame openProbe(java.lang.Object on,
                                   java.lang.String title)

Opens a probe on the given object and return its reference.

Parameters:

on - Object to be probed. If on implements the IProbeFields interface the probe will use this set of fields.

title - The title of the probe frame.

Returns:

A new instance of ProbeFrame.

openProbe

public static ProbeFrame openProbe(java.lang.Object on,
                                   java.lang.String title,
                                   ISimModel ownerModel)

Opens a probe on the given object and return its reference.

Parameters:

on - Object to be probed. If on implements the IProbeFields interface the probe will use this set of fields.

title - The title of the probe frame.

ownerModel - The caller SimModel.

Returns:

A new instance of ProbeFrame.

setCurrentClassLoader

public static void setCurrentClassLoader(DynamicClassLoader loader)

Set a new SimClassLoader.

Parameters:

loader - An instance of a class-loader to be used as SimClassLoader.

setCurrentDirectoryPath

public static void setCurrentDirectoryPath(java.lang.String newPath)

Set the current user directory path.

Parameters:

newPath - The string representing the new working directory.

setEditorPath

public static void setEditorPath(java.lang.String editorPath)

Set the external path for the code editor.

setEngine

public static void setEngine(SimEngine eng)

Set the current simulation engine.

Parameters:

eng - The simulation engine.

showMessage

public static void showMessage(java.lang.String message)

Show a system message box with the given message.

Parameters:

message - The message string to be shown.

shutdownSimulationServer

public static void shutdownSimulationServer()

Shutdown and destroy the simulation server.

startSimulationServer

public static void startSimulationServer()

Create an instance of a SimulationServer and start the service. The TCP port is the default one. See SimulationServer API for details.

startSimulationServer

public static void startSimulationServer(int onTcpPort)

Create an instance of a SimulationServer and start the service.

Parameters:

onTcpPort - The TCP port to be attached to the server.

toDays

public static long toDays(int value)

Converts the given days to the absolute time value.

Parameters:

value - The number to be converted.

Returns:

The absoulte corresponding time.

toHours

public static long toHours(int value)

Converts the given hours to the absolute time value.

Parameters:

value - The number to be converted.

Returns:

The absoulte corresponding time.

toMillis

public static long toMillis(int value)

Converts the given milliseconds to the absolute time value.

Parameters:

value - The number to be converted.

Returns:

The absoulte corresponding time.

toMins

public static long toMins(int value)

Converts the given minutes to the absolute time value.

Parameters:

value - The number to be converted.

Returns:

The absoulte corresponding time.

toMonths

public static long toMonths(int value)

Converts the given months to the absolute time value.

Parameters:

value - The number to be converted.

Returns:

The absoulte corresponding time.

toSecs

public static long toSecs(int value)

Converts the given seconds to the absolute time value.

Parameters:

value - The number to be converted.

Returns:

The absoulte corresponding time.

toYears

public static long toYears(int value)

Converts the given years to the absolute time value.

Parameters:

value - The number to be converted.

Returns:

The absoulte corresponding time.