org.jgap
Class Configuration

java.lang.Object
  org.jgap.Configuration

All Implemented Interfaces:

java.io.Serializable, Configurable

Direct Known Subclasses:

DefaultConfiguration, GPConfiguration, PermutingConfiguration

public class Configuration
extends java.lang.Object
implements Configurable, java.io.Serializable

The Configuration class represents the current configuration of plugins and parameters necessary to execute the genetic algorithm (such as fitness function, natural selector, genetic operators, and so on).

Note that, while during setup, the settings, flags, and other values may be set multiple times. But once the lockSettings() method is invoked, they cannot be changed. The default behavior of the Genotype constructor is to invoke this method, meaning that once a Configuration object is passed to a Genotype, it cannot be subsequently modified. There is no mechanism for unlocking the settings once they are locked.

Not all configuration options are required. See the documentation for each of the respective mutator methods to determine whether it is required to provide a value for that setting, and what the setting will default to if not.

Since:

1.0

See Also:

Serialized Form

Field Summary

static java.lang.String	PROPERTY_BFITFNC_INST
static java.lang.String	PROPERTY_EVENT_MGR_INST
static java.lang.String	PROPERTY_FITEVAL_INST
static java.lang.String	PROPERTY_FITFUNC_INST
static java.lang.String	PROPERTY_JGAPFACTORY_CLASS Constant for class name of JGAP Factory to use.
static java.lang.String	PROPERTY_SAMPLE_CHROM_INST
static java.lang.String	S_CHROMOSOME_SIZE
static java.lang.String	S_CONFIGURATION Constants for toString()
static java.lang.String	S_CONFIGURATION_HANDLER
static java.lang.String	S_CONFIGURATION_NAME
static java.lang.String	S_EVENT_MANAGER
static java.lang.String	S_FITNESS_EVALUATOR
static java.lang.String	S_FITNESS_FUNCTION
static java.lang.String	S_GENETIC_OPERATORS
static java.lang.String	S_MINPOPSIZE
static java.lang.String	S_NATURAL_SELECTORS
static java.lang.String	S_NONE
static java.lang.String	S_POPULATION_SIZE
static java.lang.String	S_POST
static java.lang.String	S_PRE
static java.lang.String	S_RANDOM_GENERATOR
static java.lang.String	S_SAMPLE_CHROM
static java.lang.String	S_SIZE
static java.lang.String	S_TOSTRING

Constructor Summary

Configuration()

Configuration(java.lang.String a_name)
Constructs a configuration with an informative name but without a unique ID.

Configuration(java.lang.String a_configFileName, boolean a_ignore)
Reads in the configuration from the given file.

Configuration(java.lang.String a_id, java.lang.String a_name)
Initialize with default values.

Method Summary

void	addGeneticOperator(GeneticOperator a_operatorToAdd) Adds a genetic operator for use in this algorithm.
void	addNaturalSelector(NaturalSelector a_selector, boolean a_processBeforeGeneticOperators) Adds a NaturalSelector to the ordered chain of registered NaturalSelector's.
protected void	checkProperty(java.lang.String a_propname, java.lang.Object a_obj, java.lang.String a_errmsg) Verifies that a property is not set.
BulkFitnessFunction	getBulkFitnessFunction() Retrieves the bulk fitness function previously setup in this Configuration object.
IChromosomePool	getChromosomePool() Retrieves the ChromosomePool instance, if any, that is associated with this configuration.
int	getChromosomeSize() Retrieves the chromosome size being used by this genetic algorithm.
ConfigurationHandler	getConfigurationHandler() Implementation of the Configurable interface.
IEventManager	getEventManager() Retrieves the event manager associated with this configuration.
FitnessEvaluator	getFitnessEvaluator()
FitnessFunction	getFitnessFunction() Retrieves the fitness function previously setup in this Configuration object.
int	getGenerationNr()
java.util.List	getGeneticOperators() Retrieves the genetic operators setup in this Configuration instance.
IJGAPFactory	getJGAPFactory()
int	getMinimumPopSizePercent()
java.lang.String	getName()
NaturalSelector	getNaturalSelector() Deprecated. use getNaturalSelectors(true) or getNaturalSelectors(false) to obtain the relevant chain of NaturalSelector's and then call the chain's get(index) method
NaturalSelector	getNaturalSelector(boolean a_processBeforeGeneticOperators, int a_index)
ChainOfSelectors	getNaturalSelectors(boolean a_processBeforeGeneticOperators) Only use for read-only access!
int	getNaturalSelectorsSize(boolean a_processBeforeGeneticOperators)
int	getPopulationSize() Retrieves the population size setup in this Configuration instance.
RandomGenerator	getRandomGenerator() Retrieves the random generator setup in this Configuration instance.
IChromosome	getSampleChromosome() Retrieves the sample Chromosome that contains the desired Gene setup for each respective gene position (locus).
protected static java.lang.String	getThreadKey(java.lang.Thread current, java.lang.String a_id) Builds a string considering the current thread and the given id
void	incrementGenerationNr()
boolean	isKeepPopulationSizeConstant() See setKeepPopulationSizeConstant for description.
boolean	isLocked() Retrieves the lock status of this object.
boolean	isPreserveFittestIndividual()
void	lockSettings() Locks all of the settings in this configuration object.
protected java.lang.String	makeKey(java.lang.Object a_obj)
void	removeNaturalSelectors(boolean a_processBeforeGeneticOperators) Removes all natural selectors (either pre or post ones)
static void	reset() SHOULD NOT BE NECESSARY TO CALL UNDER NORMAL CIRCUMSTANCES (may be useful for unit tests).
static void	reset(java.lang.String a_id)
static void	resetProperty(java.lang.String a_propName) See Configuration.reset().
static void	resetProperty(java.lang.String a_propName, java.lang.String a_id)
void	setBulkFitnessFunction(BulkFitnessFunction a_functionToSet) Sets the bulk fitness function to be used for this genetic algorithm.
void	setChromosomePool(IChromosomePool a_chromosomePoolToSet) Sets the ChromosomePool that is to be associated with this configuration.
void	setEventManager(IEventManager a_eventManagerToSet) Sets the event manager that is to be associated with this configuration.
void	setFitnessEvaluator(FitnessEvaluator a_fitnessEvaluator) Set the fitness evaluator (deciding if a given fitness value is better when it's higher or better when it's lower).
void	setFitnessFunction(FitnessFunction a_functionToSet) Sets the fitness function to be used for this genetic algorithm.
void	setJGAPFactory(IJGAPFactory a_factory)
void	setKeepPopulationSizeConstant(boolean a_keepPopSizeConstant) Allows to keep the population size constant after one evolution, even if there is no appropriate instance of NaturalSelector (such as WeightedRouletteSelector) registered with the Configuration.
void	setMinimumPopSizePercent(int a_minimumSizeGuaranteedPercent) Minimum size guaranteed for population.
void	setName(java.lang.String a_name)
void	setNaturalSelector(NaturalSelector a_selectorToSet) Deprecated. use addNaturalSelector(false) instead
void	setPopulationSize(int a_sizeOfPopulation) Sets the population size to be used for this genetic algorithm.
void	setPreservFittestIndividual(boolean a_preserveFittest) Determines whether to save (keep) the fittest individual.
void	setRandomGenerator(RandomGenerator a_generatorToSet) Sets the random generator to be used for this genetic algorithm.
void	setSampleChromosome(IChromosome a_sampleChromosomeToSet) Sets the sample Chromosome that is to be used as a guide for the construction of other Chromosomes.
java.lang.String	toString()
protected void	verifyChangesAllowed() Makes sure that this Configuration object isn't locked.
void	verifyStateIsValid() Tests the state of this Configuration object to make sure it's valid.

Methods inherited from class java.lang.Object

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

Field Detail

PROPERTY_JGAPFACTORY_CLASS

public static final java.lang.String PROPERTY_JGAPFACTORY_CLASS

Constant for class name of JGAP Factory to use. Use as: System.setProperty(PROPERTY_JGAPFACTORY_CLASS, "myJGAPFactory"); If none such property set, class JGAPFactory will be used.

See Also:

Constant Field Values

PROPERTY_FITFUNC_INST

public static final java.lang.String PROPERTY_FITFUNC_INST

See Also:

Constant Field Values

PROPERTY_BFITFNC_INST

public static final java.lang.String PROPERTY_BFITFNC_INST

See Also:

Constant Field Values

PROPERTY_FITEVAL_INST

public static final java.lang.String PROPERTY_FITEVAL_INST

See Also:

Constant Field Values

PROPERTY_SAMPLE_CHROM_INST

public static final java.lang.String PROPERTY_SAMPLE_CHROM_INST

See Also:

Constant Field Values

PROPERTY_EVENT_MGR_INST

public static final java.lang.String PROPERTY_EVENT_MGR_INST

See Also:

Constant Field Values

S_CONFIGURATION

public static final java.lang.String S_CONFIGURATION

Constants for toString()

See Also:

Constant Field Values

S_CONFIGURATION_NAME

public static final java.lang.String S_CONFIGURATION_NAME

See Also:

Constant Field Values

S_POPULATION_SIZE

public static final java.lang.String S_POPULATION_SIZE

See Also:

Constant Field Values

S_MINPOPSIZE

public static final java.lang.String S_MINPOPSIZE

See Also:

Constant Field Values

S_CHROMOSOME_SIZE

public static final java.lang.String S_CHROMOSOME_SIZE

See Also:

Constant Field Values

S_SAMPLE_CHROM

public static final java.lang.String S_SAMPLE_CHROM

See Also:

Constant Field Values

S_SIZE

public static final java.lang.String S_SIZE

See Also:

Constant Field Values

S_TOSTRING

public static final java.lang.String S_TOSTRING

See Also:

Constant Field Values

S_RANDOM_GENERATOR

public static final java.lang.String S_RANDOM_GENERATOR

See Also:

Constant Field Values

S_EVENT_MANAGER

public static final java.lang.String S_EVENT_MANAGER

See Also:

Constant Field Values

S_NONE

public static final java.lang.String S_NONE

See Also:

Constant Field Values

S_CONFIGURATION_HANDLER

public static final java.lang.String S_CONFIGURATION_HANDLER

See Also:

Constant Field Values

S_FITNESS_FUNCTION

public static final java.lang.String S_FITNESS_FUNCTION

See Also:

Constant Field Values

S_FITNESS_EVALUATOR

public static final java.lang.String S_FITNESS_EVALUATOR

See Also:

Constant Field Values

S_GENETIC_OPERATORS

public static final java.lang.String S_GENETIC_OPERATORS

See Also:

Constant Field Values

S_NATURAL_SELECTORS

public static final java.lang.String S_NATURAL_SELECTORS

See Also:

Constant Field Values

S_PRE

public static final java.lang.String S_PRE

See Also:

Constant Field Values

S_POST

public static final java.lang.String S_POST

See Also:

Constant Field Values

Constructor Detail

Configuration

public Configuration()

Configuration

public Configuration(java.lang.String a_id,
                     java.lang.String a_name)

Initialize with default values.

Parameters:

a_id - unique id for the configuration within the current thread

a_name - informative name of the configuration, may be null

Since:

1.0

Configuration

public Configuration(java.lang.String a_name)

Constructs a configuration with an informative name but without a unique ID. This practically prevents more than one configurations to be instantiated within the same thread.

Parameters:

a_name - informative name of the configuration, may be null

Configuration

public Configuration(java.lang.String a_configFileName,
                     boolean a_ignore)
              throws ConfigException,
                     InvalidConfigurationException

Reads in the configuration from the given file.

Parameters:

a_configFileName - the config file from which to load the configuration

a_ignore - just there to create distinct signatures :-(

Throws:

ConfigException

InvalidConfigurationException

Since:

2.3

Method Detail

reset

public static void reset()

SHOULD NOT BE NECESSARY TO CALL UNDER NORMAL CIRCUMSTANCES (may be useful for unit tests).

Reset the configuration so that re-setting parameters such as fitness function is possible (without calling this method, an overwriting of a previously set fitness function results in a RuntimeException).

Since:

3.0

reset

public static void reset(java.lang.String a_id)

resetProperty

public static void resetProperty(java.lang.String a_propName)

See Configuration.reset().

Parameters:

a_propName - the property to reset

Since:

3.0

resetProperty

public static void resetProperty(java.lang.String a_propName,
                                 java.lang.String a_id)

setName

public void setName(java.lang.String a_name)

Parameters:

a_name - informative name of the configuration

Since:

2.3

getName

public java.lang.String getName()

Returns:

informative name of the configuration

Since:

2.3

setFitnessFunction

public void setFitnessFunction(FitnessFunction a_functionToSet)
                        throws InvalidConfigurationException

Sets the fitness function to be used for this genetic algorithm. The fitness function is responsible for evaluating a given Chromosome and returning a positive integer that represents its worth as a candidate solution. These values are used as a guide by the natural to determine which Chromosome instances will be allowed to move on to the next round of evolution, and which will instead be eliminated.

Note that it is illegal to set both this fitness function and a bulk fitness function. Although one or the other must be set, the two are mutually exclusive.

Parameters:

a_functionToSet - fitness function to be used

Throws:

InvalidConfigurationException - if the fitness function is null, a bulk fitness function has already been set, or if this Configuration object is locked.

Since:

1.1

checkProperty

protected void checkProperty(java.lang.String a_propname,
                             java.lang.Object a_obj,
                             java.lang.String a_errmsg)

Verifies that a property is not set. If not set, set it, otherwise throw a RuntimeException with a_errmsg as text.

Parameters:

a_propname - the property to check (the current thread will be considered as a part of the property's name, too)

a_obj - the object that should be set in charge of the property

a_errmsg - the error message to throw in case the property is already set for the current thread

Since:

3.0

makeKey

protected java.lang.String makeKey(java.lang.Object a_obj)

Parameters:

a_obj - the object to make a key for, must not be null

Returns:

key produced for the object (hashCode() is used, so it should be implemented properly!)

Since:

3.0

getFitnessFunction

public FitnessFunction getFitnessFunction()

Retrieves the fitness function previously setup in this Configuration object.

Returns:

the fitness function

Since:

1.0

setBulkFitnessFunction

public void setBulkFitnessFunction(BulkFitnessFunction a_functionToSet)
                            throws InvalidConfigurationException

Sets the bulk fitness function to be used for this genetic algorithm. The bulk fitness function may be used to evaluate and assign fitness values to the entire group of candidate Chromosomes in a single batch. This can be useful in cases where it's difficult to assign fitness values to a Chromosome in isolation from the other candidate Chromosomes.

Note that it is illegal to set both a bulk fitness function and a normal fitness function. Although one or the other is required, the two are mutually exclusive.

Parameters:

a_functionToSet - bulk fitness function to be used

Throws:

InvalidConfigurationException - if the bulk fitness function is null, the normal fitness function has already been set, or if this Configuration object is locked

Since:

1.0

getBulkFitnessFunction

public BulkFitnessFunction getBulkFitnessFunction()

Retrieves the bulk fitness function previously setup in this Configuration object.

Returns:

The bulk fitness function

Since:

1.0

setSampleChromosome

public void setSampleChromosome(IChromosome a_sampleChromosomeToSet)
                         throws InvalidConfigurationException

Sets the sample Chromosome that is to be used as a guide for the construction of other Chromosomes. The Chromosome should be setup with each gene represented by the desired concrete Gene implementation for that gene position (locus). Anytime a new Chromosome is created, it will be constructed with the same Gene setup as that provided in this sample Chromosome.

Parameters:

a_sampleChromosomeToSet - Chromosome to be used as the sample

Throws:

InvalidConfigurationException - if the given Chromosome is null or this Configuration object is locked

Since:

1.0

getSampleChromosome

public IChromosome getSampleChromosome()

Retrieves the sample Chromosome that contains the desired Gene setup for each respective gene position (locus).

Returns:

sample Chromosome instance

Since:

1.0

getChromosomeSize

public int getChromosomeSize()

Retrieves the chromosome size being used by this genetic algorithm. This value is set automatically when the sample chromosome is provided.

Returns:

chromosome size used in this configuration

Since:

1.0

setNaturalSelector

public void setNaturalSelector(NaturalSelector a_selectorToSet)
                        throws InvalidConfigurationException

Deprecated. use addNaturalSelector(false) instead

Sets the natural selector to be used for this genetic algorithm. The natural selector is responsible for actually selecting which Chromosome instances are allowed to move on to the next round of evolution (usually guided by the fitness values provided by the fitness function). This setting is required.

Parameters:

a_selectorToSet - the natural selector to be used

Throws:

InvalidConfigurationException - if the natural selector is null or this Configuration object is locked

Since:

1.0

getNaturalSelector

public NaturalSelector getNaturalSelector()

Deprecated. use getNaturalSelectors(true) or getNaturalSelectors(false) to obtain the relevant chain of NaturalSelector's and then call the chain's get(index) method

Retrieves the natural selector setup in this Configuration instance.

Returns:

the natural selector

Since:

1.0

getNaturalSelector

public NaturalSelector getNaturalSelector(boolean a_processBeforeGeneticOperators,
                                          int a_index)

Parameters:

a_processBeforeGeneticOperators - boolean

a_index - int

Returns:

NaturalSelector

Since:

1.1

getNaturalSelectors

public ChainOfSelectors getNaturalSelectors(boolean a_processBeforeGeneticOperators)

Only use for read-only access! Especially don't call clear() for the returned ChainOfSelectors object!

Parameters:

a_processBeforeGeneticOperators - boolean

Returns:

ChainOfSelectors

Since:

1.1

getNaturalSelectorsSize

public int getNaturalSelectorsSize(boolean a_processBeforeGeneticOperators)

Parameters:

a_processBeforeGeneticOperators - boolean

Returns:

int

Since:

1.1

removeNaturalSelectors

public void removeNaturalSelectors(boolean a_processBeforeGeneticOperators)

Removes all natural selectors (either pre or post ones)

Parameters:

a_processBeforeGeneticOperators - true: remove all selectors processed before genetic operators, false: remove the ones processed afterwards

Since:

2.3

setRandomGenerator

public void setRandomGenerator(RandomGenerator a_generatorToSet)
                        throws InvalidConfigurationException

Sets the random generator to be used for this genetic algorithm. The random generator is responsible for generating random numbers, which are used throughout the process of genetic evolution and selection. This setting is required.

Parameters:

a_generatorToSet - random generator to be used

Throws:

InvalidConfigurationException - if the random generator is null or this object is locked

Since:

1.0

getRandomGenerator

public RandomGenerator getRandomGenerator()

Retrieves the random generator setup in this Configuration instance.

Returns:

the random generator

Since:

1.0

addGeneticOperator

public void addGeneticOperator(GeneticOperator a_operatorToAdd)
                        throws InvalidConfigurationException

Adds a genetic operator for use in this algorithm. Genetic operators represent evolutionary steps that, when combined, make up the evolutionary process. Examples of genetic operators are reproduction, crossover, and mutation. During the evolution process, all of the genetic operators added via this method are invoked in the order they were added. At least one genetic operator must be provided.

Parameters:

a_operatorToAdd - The genetic operator to add.

Throws:

InvalidConfigurationException - if the genetic operator is null or if this Configuration object is locked

Since:

1.0

getGeneticOperators

public java.util.List getGeneticOperators()

Retrieves the genetic operators setup in this Configuration instance. Note that once this Configuration instance is locked, a new, immutable list of operators is used and any lists previously retrieved with this method will no longer reflect the actual list in use.

Returns:

The list of genetic operators

Since:

1.0

setPopulationSize

public void setPopulationSize(int a_sizeOfPopulation)
                       throws InvalidConfigurationException

Sets the population size to be used for this genetic algorithm. The population size is a fixed value that represents the number of Chromosomes contained within the Genotype (population). This setting is required.

Parameters:

a_sizeOfPopulation - population size to be used

Throws:

InvalidConfigurationException - if the population size is not positive or this object is locked

Since:

1.0

getPopulationSize

public int getPopulationSize()

Retrieves the population size setup in this Configuration instance.

Returns:

population size

setEventManager

public void setEventManager(IEventManager a_eventManagerToSet)
                     throws InvalidConfigurationException

Sets the event manager that is to be associated with this configuration. The event manager is responsible for the management of event subscribers and event notifications.

Parameters:

a_eventManagerToSet - the EventManager instance to use in this configuration

Throws:

InvalidConfigurationException - if the event manager is null or this Configuration object is locked

Since:

1.0

getEventManager

public IEventManager getEventManager()

Retrieves the event manager associated with this configuration. The event manager is responsible for the management of event subscribers and event notifications.

Returns:

the actively configured event manager instance

setChromosomePool

public void setChromosomePool(IChromosomePool a_chromosomePoolToSet)
                       throws InvalidConfigurationException

Sets the ChromosomePool that is to be associated with this configuration. The ChromosomePool is used to pool discarded Chromosome instances so that they may be recycled later, thereby saving memory and the time to construct them from scratch. The presence of a ChromosomePool is optional. If none exists, then a new Chromosome will be constructed each time one is needed.

Parameters:

a_chromosomePoolToSet - the ChromosomePool instance to use

Throws:

InvalidConfigurationException - if this object is locked

Since:

1.0

getChromosomePool

public IChromosomePool getChromosomePool()

Retrieves the ChromosomePool instance, if any, that is associated with this configuration. The ChromosomePool is used to pool discarded Chromosome instances so that they may be recycled later, thereby saving memory and the time to construct them from scratch. The presence of a ChromosomePool instance is optional. If none exists, then new Chromosomes should be constructed each time one is needed.

Returns:

The ChromosomePool instance associated this configuration, or null if none has been provided

Since:

1.0

lockSettings

public void lockSettings()
                  throws InvalidConfigurationException

Locks all of the settings in this configuration object. Once this method is successfully invoked, none of the settings may be changed. There is no way to unlock this object once it is locked.

Prior to returning successfully, this method will first invoke the verifyStateIsValid() method to make sure that any required configuration options have been properly set. If it detects a problem, it will throw an InvalidConfigurationException and leave the object unlocked.

It's possible to test whether this object is locked through the isLocked() method.

It is ok to lock an object more than once. In that case, this method does nothing and simply returns.

Throws:

InvalidConfigurationException - if this Configuration object is in an invalid state at the time of invocation

Since:

1.0

isLocked

public boolean isLocked()

Retrieves the lock status of this object.

Returns:

true if this object has been locked by a previous successful call to the lockSettings() method, false otherwise

Since:

1.0

verifyStateIsValid

public void verifyStateIsValid()
                        throws InvalidConfigurationException

Tests the state of this Configuration object to make sure it's valid. This generally consists of verifying that required settings have, in fact, been set. If this object is not in a valid state, then an exception will be thrown detailing the reason the state is not valid.

Throws:

InvalidConfigurationException - if the state of this Configuration is not valid. The error message in the exception will detail the reason for invalidity

Since:

1.0

verifyChangesAllowed

protected void verifyChangesAllowed()
                             throws InvalidConfigurationException

Makes sure that this Configuration object isn't locked. If it is, then an exception is thrown with an appropriate message indicating that settings in this object may not be altered. This method should be invoked by any mutator method in this object prior to making any state alterations.

Throws:

InvalidConfigurationException - if this Configuration object is locked

Since:

1.0

addNaturalSelector

public void addNaturalSelector(NaturalSelector a_selector,
                               boolean a_processBeforeGeneticOperators)
                        throws InvalidConfigurationException

Adds a NaturalSelector to the ordered chain of registered NaturalSelector's. It's possible to execute the NaturalSelector before or after (registered) genetic operations have been applied.

Parameters:

a_selector - the selector to be added to the chain

a_processBeforeGeneticOperators - true: execute NaturalSelector before any genetic operator will be applied, false: .. after..

Throws:

InvalidConfigurationException

Since:

1.1

setMinimumPopSizePercent

public void setMinimumPopSizePercent(int a_minimumSizeGuaranteedPercent)

Minimum size guaranteed for population. This is significant during evolution as natural selectors could select fewer chromosomes for the next generation than the initial population size was.

Parameters:

a_minimumSizeGuaranteedPercent - if zero or below then no ensurance for size given, see Genotype.evolve()

getMinimumPopSizePercent

public int getMinimumPopSizePercent()

getFitnessEvaluator

public FitnessEvaluator getFitnessEvaluator()

Returns:

the assigned FitnessEvaluator

Since:

2.0

setFitnessEvaluator

public void setFitnessEvaluator(FitnessEvaluator a_fitnessEvaluator)

Set the fitness evaluator (deciding if a given fitness value is better when it's higher or better when it's lower).

Parameters:

a_fitnessEvaluator - the FitnessEvaluator to be used

Since:

2.0

isPreserveFittestIndividual

public boolean isPreserveFittestIndividual()

Returns:

true: fittest chromosome should always be transferred to next generation

Since:

2.1

setPreservFittestIndividual

public void setPreservFittestIndividual(boolean a_preserveFittest)

Determines whether to save (keep) the fittest individual.

Parameters:

a_preserveFittest - true: always transfer fittest chromosome to next generation

Since:

2.1

incrementGenerationNr

public void incrementGenerationNr()

getGenerationNr

public int getGenerationNr()

getConfigurationHandler

public ConfigurationHandler getConfigurationHandler()

Implementation of the Configurable interface.

Returns:

ConfigurationHandler

Throws:

ConfigException

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

Returns:

string representation of the configuration containing all configurable elements

Since:

2.3

isKeepPopulationSizeConstant

public boolean isKeepPopulationSizeConstant()

See setKeepPopulationSizeConstant for description.

Returns:

true: population size will always be the same size (as given with Configuration.setPopulationSize(int)

Since:

2.4

setKeepPopulationSizeConstant

public void setKeepPopulationSizeConstant(boolean a_keepPopSizeConstant)

Allows to keep the population size constant after one evolution, even if there is no appropriate instance of NaturalSelector (such as WeightedRouletteSelector) registered with the Configuration.

Be aware that keeping the population size constant often means that a higher population size is necessary (e.g. for the MinimizingMakeChange example)!

Parameters:

a_keepPopSizeConstant - true: population size will always be the same size (as given with Configuration.setPopulationSize(int)

Since:

2.4

getJGAPFactory

public IJGAPFactory getJGAPFactory()

getThreadKey

protected static java.lang.String getThreadKey(java.lang.Thread current,
                                               java.lang.String a_id)

Builds a string considering the current thread and the given id

Parameters:

current - the current Thread

a_id - a hopefully unique id of the configuration

Returns:

string built up

Since:

3.01

setJGAPFactory

public void setJGAPFactory(IJGAPFactory a_factory)

Parameters:

a_factory - the IJGAPFactory to use

Since:

3.01