Module io.jenetics.base

Package io.jenetics

Class Phenotype<G extends Gene<?,G>,C extends Comparable<? super C>>

java.lang.Object

io.jenetics.Phenotype<G,C>

Type Parameters:

G - the gene type

C - the fitness result type

All Implemented Interfaces:

Verifiable, Serializable, Comparable<Phenotype<G,C>>

public final class Phenotype<G extends Gene<?,G>,C extends Comparable<? super C>>
extends Object
implements Comparable<Phenotype<G,C>>, Verifiable, Serializable

The Phenotype consists of a Genotype, the current generation and an optional fitness value. Once the fitness has been evaluated, a new Phenotype instance, with the calculated fitness, can be created with the withFitness(Comparable).

Since:

1.0

Version:

6.0

See Also:

• Genotype
• Serialized Form

Implementation Note:

This class is immutable and thread-safe.

Method Summary

Modifier and Type	Method	Description
long	age(long currentGeneration)	Return the age of this phenotype depending on the given current generation.
int	compareTo(Phenotype<G,C> pt)
boolean	equals(Object obj)
Phenotype<G,C>	eval(Function<? super Genotype<G>,? extends C> ff)	Applies the given fitness function to the underlying genotype and return a new phenotype with the (newly) evaluated fitness function, if not already evaluated.
C	fitness()	Return the fitness value of this Phenotype.
Optional<C>	fitnessOptional()	Return the fitness value of this phenotype, or Optional.empty() if not evaluated yet.
long	generation()	Return the generation this Phenotype was created.
Genotype<G>	genotype()	This method returns a copy of the Genotype, to guarantee a immutable class.
int	hashCode()
boolean	isEvaluated()	A phenotype instance can be created with or without fitness value.
boolean	isValid()	Test whether this phenotype is valid.
boolean	nonEvaluated()	A phenotype instance can be created with or without fitness value.
Phenotype<G,C>	nullifyFitness()	Return a phenotype, where the fitness is set to null.
static <G extends Gene<?, G>, C extends Comparable<? super C>> Phenotype<G,C>	of(Genotype<G> genotype, long generation)	Create a new phenotype from the given arguments.
static <G extends Gene<?, G>, C extends Comparable<? super C>> Phenotype<G,C>	of(Genotype<G> genotype, long generation, C fitness)	Create a new phenotype from the given arguments.
String	toString()
Phenotype<G,C>	withFitness(C fitness)	Return a new Phenotype object with the given raw fitness value.
Phenotype<G,C>	withGeneration(long generation)	Return a new Phenotype object with the given generation.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Details

eval

public Phenotype<G,C> eval(Function<? super Genotype<G>,? extends C> ff)

Applies the given fitness function to the underlying genotype and return a new phenotype with the (newly) evaluated fitness function, if not already evaluated. If the fitness value is already set this phenotype is returned.

Parameters:

ff - the fitness function

Returns:

an evaluated phenotype or this if the fitness value is already set

Throws:

NullPointerException - if the given fitness function is null

Since:

5.0

genotype

public Genotype<G> genotype()

This method returns a copy of the Genotype, to guarantee a immutable class.

Returns:

the cloned Genotype of this Phenotype.

Throws:

NullPointerException - if one of the arguments is null.

isEvaluated

public boolean isEvaluated()

A phenotype instance can be created with or without fitness value. Initially, the phenotype is created without fitness value. The fitness evaluation strategy is responsible for creating phenotypes with fitness value assigned.

Returns:

true is this phenotype has a fitness value assigned, false otherwise

Since:

4.2

See Also:

• nonEvaluated()

nonEvaluated

public boolean nonEvaluated()

A phenotype instance can be created with or without fitness value. Initially, the phenotype is created without fitness value. The fitness evaluation strategy is responsible for creating phenotypes with fitness value assigned.

Returns:

false is this phenotype has a fitness value assigned, true otherwise

Since:

5.0

See Also:

• isEvaluated()

fitness

public C fitness()

Return the fitness value of this Phenotype.

Returns:

The fitness value of this Phenotype.

Throws:

NoSuchElementException - if isEvaluated() returns false

See Also:

• fitnessOptional()

fitnessOptional

public Optional<C> fitnessOptional()

Return the fitness value of this phenotype, or Optional.empty() if not evaluated yet.

Returns:

the fitness value

Since:

5.0

See Also:

• fitness()

generation

public long generation()

Return the generation this Phenotype was created.

Returns:

The generation this Phenotype was created.

See Also:

• age(long)

age

public long age(long currentGeneration)

Return the age of this phenotype depending on the given current generation.

Parameters:

currentGeneration - the current generation evaluated by the GA.

Returns:

the age of this phenotype: currentGeneration - this.getGeneration().

See Also:

• generation()

nullifyFitness

public Phenotype<G,C> nullifyFitness()

Return a phenotype, where the fitness is set to null. If this phenotype isn't evaluated, this instance is returned.

Returns:

a phenotype, where the fitness is set to null

Since:

6.0

isValid

public boolean isValid()

Test whether this phenotype is valid. The phenotype is valid if its Genotype is valid.

Specified by:

isValid in interface Verifiable

Returns:

true if this phenotype is valid, false otherwise.

compareTo

public int compareTo(Phenotype<G,C> pt)

Specified by:

compareTo in interface Comparable<G extends Gene<?,G>>

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object

withFitness

public Phenotype<G,C> withFitness(C fitness)

Return a new Phenotype object with the given raw fitness value. The returned phenotype is automatically evaluated: isEvaluated() == true

Parameters:

fitness - the phenotypes' fitness value

Returns:

a new phenotype with the given fitness value

Throws:

NullPointerException - if the given fitness value is null

Since:

4.2

withGeneration

public Phenotype<G,C> withGeneration(long generation)

Return a new Phenotype object with the given generation.

Parameters:

generation - the generation of the newly created phenotype

Returns:

a new phenotype with the given generation

Since:

5.0

of

public static <G extends Gene<?,
G>,
C extends Comparable<? super C>>
Phenotype<G,C> of(Genotype<G> genotype,
 long generation)

Create a new phenotype from the given arguments. The phenotype is created with a non-assigned fitness function and the call of isEvaluated() will return false.

Type Parameters:

G - the gene type of the chromosome

C - the fitness value type

Parameters:

genotype - the genotype of this phenotype.

generation - the current generation of the generated phenotype.

Returns:

a new phenotype object

Throws:

NullPointerException - if one of the arguments is null.

IllegalArgumentException - if the given generation is < 0.

of

public static <G extends Gene<?,
G>,
C extends Comparable<? super C>>
Phenotype<G,C> of(Genotype<G> genotype,
 long generation,
 C fitness)

Create a new phenotype from the given arguments.

Type Parameters:

G - the gene type of the chromosome

C - the fitness value type

Parameters:

genotype - the genotype of this phenotype.

generation - the current generation of the generated phenotype.

fitness - the known fitness of the phenotype.

Returns:

a new phenotype object

Throws:

NullPointerException - if one of the arguments is null.

IllegalArgumentException - if the given generation is < 0.