Package org.uma.evolver.algorithm.meta

Class MetaNSGAIIBuilder

java.lang.Object

org.uma.evolver.algorithm.meta.MetaNSGAIIBuilder

public class MetaNSGAIIBuilder
extends Object

Builder for creating NSGA-II instances configured for meta-optimization tasks with double solutions. This builder provides sensible defaults for meta-optimization scenarios and internally manages SBX crossover and polynomial mutation operators.

The builder follows the builder pattern for easy configuration of NSGA-II parameters and creates a fully configured NSGA-II instance ready for execution.

Example usage:

 MetaNSGAIIBuilder builder = new MetaNSGAIIBuilder(problem)
     .setPopulationSize(100)
     .setMaxEvaluations(10000)
     .setNumberOfCores(4);
 EvolutionaryAlgorithm<DoubleSolution> nsgaii = builder.build();
 

See Also:

• EvolutionaryAlgorithm
• DoubleNSGAII
• MetaOptimizationProblem

Constructor Summary

Constructors

Constructor	Description
MetaNSGAIIBuilder(MetaOptimizationProblem<?> problem, ParameterSpace parameterSpace)	Creates a new builder with the specified meta-optimization problem.

Method Summary

Modifier and Type	Method	Description
org.uma.jmetal.component.algorithm.EvolutionaryAlgorithm<org.uma.jmetal.solution.doublesolution.DoubleSolution>	build()	Builds and configures an NSGA-II instance with the specified parameters.
MetaNSGAIIBuilder	setMaxEvaluations(int maxEvaluations)	Sets the maximum number of evaluations for the NSGA-II algorithm.
MetaNSGAIIBuilder	setMutationProbabilityFactor(double mutationProbabilityFactor)	Sets the mutation probability factor for the NSGA-II algorithm.
MetaNSGAIIBuilder	setNumberOfCores(int numberOfCores)	Sets the number of cores to use for parallel evaluation.
MetaNSGAIIBuilder	setOffspringPopulationSize(int offspringPopulationSize)	Sets the offspring population size for the NSGA-II algorithm.
MetaNSGAIIBuilder	setPopulationSize(int populationSize)	Sets the population size for the NSGA-II algorithm.

Methods inherited from class java.lang.Object

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

Constructor Details

MetaNSGAIIBuilder

public MetaNSGAIIBuilder(MetaOptimizationProblem<?> problem,
 ParameterSpace parameterSpace)

Creates a new builder with the specified meta-optimization problem.

Parameters:

problem - the meta-optimization problem to be solved (must not be null)

Throws:

org.uma.jmetal.util.errorchecking.JMetalException - if the problem is null

Method Details

setPopulationSize

public MetaNSGAIIBuilder setPopulationSize(int populationSize)

Sets the population size for the NSGA-II algorithm.

Parameters:

populationSize - the population size (must be non-negative)

Returns:

this builder instance for method chaining

Throws:

org.uma.jmetal.util.errorchecking.JMetalException - if populationSize is negative

setOffspringPopulationSize

public MetaNSGAIIBuilder setOffspringPopulationSize(int offspringPopulationSize)

Sets the offspring population size for the NSGA-II algorithm.

Parameters:

offspringPopulationSize - the offspring population size (must be positive)

Returns:

this builder instance for method chaining

Throws:

org.uma.jmetal.util.errorchecking.JMetalException - if offspringPopulationSize is not positive

setMaxEvaluations

public MetaNSGAIIBuilder setMaxEvaluations(int maxEvaluations)

Sets the maximum number of evaluations for the NSGA-II algorithm.

Parameters:

maxEvaluations - the maximum number of evaluations (must be non-negative)

Returns:

this builder instance for method chaining

Throws:

org.uma.jmetal.util.errorchecking.JMetalException - if maxEvaluations is negative

setNumberOfCores

public MetaNSGAIIBuilder setNumberOfCores(int numberOfCores)

Sets the number of cores to use for parallel evaluation.

Parameters:

numberOfCores - the number of CPU cores to use (must be non-negative)

Returns:

this builder instance for method chaining

Throws:

org.uma.jmetal.util.errorchecking.JMetalException - if numberOfCores is negative

setMutationProbabilityFactor

public MetaNSGAIIBuilder setMutationProbabilityFactor(double mutationProbabilityFactor)

Sets the mutation probability factor for the NSGA-II algorithm.

Parameters:

mutationProbabilityFactor - the mutation probability factor (must be non-negative)

Returns:

this builder instance for method chaining

Throws:

org.uma.jmetal.util.errorchecking.JMetalException - if mutationProbabilityFactor is negative

build

public org.uma.jmetal.component.algorithm.EvolutionaryAlgorithm<org.uma.jmetal.solution.doublesolution.DoubleSolution> build()

Builds and configures an NSGA-II instance with the specified parameters.

The returned NSGA-II instance is configured with the following default operators:

• SBX Crossover (probability=0.9, distribution index=20.0)
• Polynomial Mutation (probability=1.0, distribution index=20.0)
• Tournament Selection (tournament size=2)
• Multi-threaded evaluation

Returns:

a fully configured NSGA-II instance ready for execution

Throws:

org.uma.jmetal.util.errorchecking.JMetalException - if the configuration is invalid