AddNodePolicyHandler.java

package net.bmahe.genetics4j.neat.mutation;

import java.util.random.RandomGenerator;

import org.apache.commons.lang3.Validate;

import net.bmahe.genetics4j.core.chromosomes.Chromosome;
import net.bmahe.genetics4j.core.mutation.GenericMutatorImpl;
import net.bmahe.genetics4j.core.mutation.MutationPolicyHandler;
import net.bmahe.genetics4j.core.mutation.MutationPolicyHandlerResolver;
import net.bmahe.genetics4j.core.mutation.Mutator;
import net.bmahe.genetics4j.core.mutation.chromosome.ChromosomeMutationHandler;
import net.bmahe.genetics4j.core.spec.AbstractEAConfiguration;
import net.bmahe.genetics4j.core.spec.AbstractEAExecutionContext;
import net.bmahe.genetics4j.core.spec.mutation.MutationPolicy;
import net.bmahe.genetics4j.core.util.ChromosomeResolverUtils;
import net.bmahe.genetics4j.neat.spec.mutation.AddNode;

public class AddNodePolicyHandler<T extends Comparable<T>> implements MutationPolicyHandler<T> {

	private final RandomGenerator randomGenerator;

	public AddNodePolicyHandler(final RandomGenerator _randomGenerator) {
		Validate.notNull(_randomGenerator);

		this.randomGenerator = _randomGenerator;
	}

	@Override
	public boolean canHandle(final MutationPolicyHandlerResolver<T> mutationPolicyHandlerResolver,
			final MutationPolicy mutationPolicy) {
		Validate.notNull(mutationPolicyHandlerResolver);
		Validate.notNull(mutationPolicy);

		return mutationPolicy instanceof AddNode;
	}

	@Override
	public Mutator createMutator(final AbstractEAExecutionContext<T> eaExecutionContext,
			final AbstractEAConfiguration<T> eaConfiguration,
			final MutationPolicyHandlerResolver<T> mutationPolicyHandlerResolver, MutationPolicy mutationPolicy) {
		Validate.notNull(eaExecutionContext);
		Validate.notNull(eaConfiguration);
		Validate.notNull(mutationPolicy);
		Validate.notNull(mutationPolicyHandlerResolver);

		final AddNode addNodeMutationPolicy = (AddNode) mutationPolicy;
		final double populationMutationProbability = addNodeMutationPolicy.populationMutationProbability();

		final ChromosomeMutationHandler<? extends Chromosome>[] chromosomeMutationHandlers = ChromosomeResolverUtils
				.resolveChromosomeMutationHandlers(eaExecutionContext, eaConfiguration, mutationPolicy);

		return new GenericMutatorImpl(randomGenerator,
				chromosomeMutationHandlers,
				mutationPolicy,
				populationMutationProbability);
	}
}