1 package net.bmahe.genetics4j.core.selection;
2
3 import java.util.List;
4 import java.util.Objects;
5
6 import org.apache.commons.lang3.Validate;
7
8 import net.bmahe.genetics4j.core.Genotype;
9 import net.bmahe.genetics4j.core.Population;
10 import net.bmahe.genetics4j.core.spec.AbstractEAConfiguration;
11 import net.bmahe.genetics4j.core.spec.AbstractEAExecutionContext;
12 import net.bmahe.genetics4j.core.spec.selection.SelectAll;
13 import net.bmahe.genetics4j.core.spec.selection.SelectionPolicy;
14
15 public class SelectAllPolicyHandler<T extends Comparable<T>> implements SelectionPolicyHandler<T> {
16
17 public SelectAllPolicyHandler() {
18 }
19
20 @Override
21 public boolean canHandle(final SelectionPolicy selectionPolicy) {
22 Objects.requireNonNull(selectionPolicy);
23 return selectionPolicy instanceof SelectAll;
24 }
25
26 @Override
27 public Selector<T> resolve(AbstractEAExecutionContext<T> eaExecutionContext,
28 AbstractEAConfiguration<T> eaConfiguration, SelectionPolicyHandlerResolver<T> selectionPolicyHandlerResolver,
29 SelectionPolicy selectionPolicy) {
30 Objects.requireNonNull(selectionPolicy);
31 Validate.isInstanceOf(SelectAll.class, selectionPolicy);
32
33 return new Selector<>() {
34
35 @Override
36 public Population<T> select(final AbstractEAConfiguration<T> eaConfiguration, final long generation,
37 final int numIndividuals, final List<Genotype> population, final List<T> fitnessScore) {
38 Objects.requireNonNull(eaConfiguration);
39 Objects.requireNonNull(population);
40 Objects.requireNonNull(fitnessScore);
41 Validate.isTrue(numIndividuals > 0);
42 Validate.isTrue(population.isEmpty() == false, "population cannot be empty");
43 Validate.isTrue(fitnessScore.isEmpty() == false, "fitnessScore cannot be empty");
44 Validate.isTrue(fitnessScore.size() == population.size());
45
46 final Population<T> selected = new Population<>();
47
48 int i = 0;
49 while (selected.size() < numIndividuals) {
50 selected.add(population.get(i), fitnessScore.get(i));
51
52 i = (i + 1) % population.size();
53 }
54
55 return selected;
56 }
57 };
58 }
59 }