org.jgap.impl
Class StringGene

java.lang.Object
  org.jgap.impl.StringGene

All Implemented Interfaces:

java.lang.Comparable, Gene, java.io.Serializable

public class StringGene

extends java.lang.Object

implements Gene

A Gene implementation that supports a string for its allele. The valid alphabet as well as the minimum and maximum length of the string can be specified.

An alphabet == null indicates that all characters are seen as valid.
An alphabet == "" indicates that no character is seen to be valid.

Partly copied from IntegerGene.

Since:

1.1

Author:

Klaus Meffert, Audrius Meskauskas

See Also:

Serialized Form

Field Summary

static java.lang.String	ALPHABET_CHARACTERS_DIGITS
static java.lang.String	ALPHABET_CHARACTERS_LOWER
static java.lang.String	ALPHABET_CHARACTERS_SPECIAL
static java.lang.String	ALPHABET_CHARACTERS_UPPER

Fields inherited from interface org.jgap.Gene

PERSISTENT_FIELD_DELIMITER

Constructor Summary

StringGene()

StringGene(int a_minLength, int a_maxLength)

StringGene(int a_minLength, int a_maxLength, java.lang.String a_alphabet)

Method Summary

void	applyMutation(int index, double a_percentage) Applies a mutation of a given intensity (percentage) onto the atomic element at given index (NumberGenes only have one atomic element)
void	cleanup() Executed by the genetic engine when this Gene instance is no longer needed and should perform any necessary resource cleanup.
int	compareTo(java.lang.Object other) Compares this StringGene with the specified object (which must also be a StringGene) for order, which is determined by the String value of this Gene compared to the one provided for comparison.
boolean	equals(java.lang.Object other) Compares this Gene with the given object and returns true if the other object is a Gene of this type and has the same value (allele) as this Gene.
java.lang.Object	getAllele() Retrieves the value (allele) represented by this Gene.
java.lang.String	getAlphabet()
IGeneConstraintChecker	getConstraintChecker()
int	getMaxLength()
int	getMinLength()
java.lang.String	getPersistentRepresentation() Retrieves a string representation of this Gene that includes any information required to reconstruct it at a later time, such as its value and internal state.
int	hashCode() Retrieves the hash code value for this StringGene.
Gene	newGene() Provides an implementation-independent means for creating new Gene instances.
void	setAllele(java.lang.Object a_newValue) Sets the value (allele) of this Gene to the new given value.
void	setAlphabet(java.lang.String a_alphabet) Sets the valid alphabet of the StringGene
void	setConstraintChecker(IGeneConstraintChecker a_constraintChecker) Sets the constraint checker to be used for this gene whenever method setAllele(Object a_newValue) is called
void	setMaxLength(int m_maxLength)
void	setMinLength(int m_minLength)
void	setToRandomValue(RandomGenerator a_numberGenerator) Sets the value (allele) of this Gene to a random String according to the valid alphabet and boundaries of length
void	setValueFromPersistentRepresentation(java.lang.String a_representation) Sets the value and internal state of this Gene from the string representation returned by a previous invocation of the getPersistentRepresentation() method.
int	size()
java.lang.String	stringValue() Retrieves the String value of this Gene, which may be more convenient in some cases than the more general getAllele() method.
java.lang.String	toString() Retrieves a string representation of this StringGene's value that may be useful for display purposes.

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Field Detail

ALPHABET_CHARACTERS_UPPER

public static final java.lang.String ALPHABET_CHARACTERS_UPPER

See Also:

Constant Field Values

ALPHABET_CHARACTERS_LOWER

public static final java.lang.String ALPHABET_CHARACTERS_LOWER

See Also:

Constant Field Values

ALPHABET_CHARACTERS_DIGITS

public static final java.lang.String ALPHABET_CHARACTERS_DIGITS

See Also:

Constant Field Values

ALPHABET_CHARACTERS_SPECIAL

public static final java.lang.String ALPHABET_CHARACTERS_SPECIAL

See Also:

Constant Field Values

Constructor Detail

StringGene

public StringGene()

Since:

1.1

StringGene

public StringGene(int a_minLength,
                  int a_maxLength)

Parameters:

a_minLength - minimum valid length of allele

a_maxLength - maximum valid length of allele

Since:

1.1

StringGene

public StringGene(int a_minLength,
                  int a_maxLength,
                  java.lang.String a_alphabet)

Parameters:

a_minLength - minimum valid length of allele

a_maxLength - maximum valid length of allele

a_alphabet - valid aplhabet for allele

Since:

2.0

Method Detail

cleanup

public void cleanup()

Executed by the genetic engine when this Gene instance is no longer needed and should perform any necessary resource cleanup.

Specified by:

cleanup in interface Gene

Since:

1.1

setToRandomValue

public void setToRandomValue(RandomGenerator a_numberGenerator)

Sets the value (allele) of this Gene to a random String according to the valid alphabet and boundaries of length

Specified by:

setToRandomValue in interface Gene

Parameters:

a_numberGenerator - The random number generator that should be used to create any random values. It's important to use this generator to maintain the user's flexibility to configure the genetic engine to use the random number generator of their choice.

Since:

1.1

setValueFromPersistentRepresentation

public void setValueFromPersistentRepresentation(java.lang.String a_representation)
                                          throws UnsupportedRepresentationException

Sets the value and internal state of this Gene from the string representation returned by a previous invocation of the getPersistentRepresentation() method. This is an optional method but, if not implemented, XML persistence and possibly other features will not be available. An UnsupportedOperationException should be thrown if no implementation is provided.

Specified by:

setValueFromPersistentRepresentation in interface Gene

Parameters:

a_representation - the string representation retrieved from a prior call to the getPersistentRepresentation() method.

Throws:

java.lang.UnsupportedOperationException - to indicate that no implementation is provided for this method.

UnsupportedRepresentationException - if this Gene implementation does not support the given string representation.

Since:

1.1

getPersistentRepresentation

public java.lang.String getPersistentRepresentation()
                                             throws java.lang.UnsupportedOperationException

Retrieves a string representation of this Gene that includes any information required to reconstruct it at a later time, such as its value and internal state. This string will be used to represent this Gene in XML persistence. This is an optional method but, if not implemented, XML persistence and possibly other features will not be available. An UnsupportedOperationException should be thrown if no implementation is provided.

Specified by:

getPersistentRepresentation in interface Gene

Returns:

A string representation of this Gene's current state.

Throws:

java.lang.UnsupportedOperationException - to indicate that no implementation is provided for this method.

Since:

1.1

getAllele

public java.lang.Object getAllele()

Retrieves the value (allele) represented by this Gene. All values returned by this class will be String instances.

Specified by:

getAllele in interface Gene

Returns:

the String value of this Gene.

Since:

1.1

setAllele

public void setAllele(java.lang.Object a_newValue)

Sets the value (allele) of this Gene to the new given value. This class expects the value to be a String instance. If the value is shorter or longer than the minimum or maximum length or any character is not within the valid alphabet an exception is throwsn

Specified by:

setAllele in interface Gene

Parameters:

a_newValue - the new value of this Gene instance.

Since:

1.1

setConstraintChecker

public void setConstraintChecker(IGeneConstraintChecker a_constraintChecker)

Sets the constraint checker to be used for this gene whenever method setAllele(Object a_newValue) is called

Parameters:

a_constraintChecker - the constraint checker to be set

Since:

2.0

getConstraintChecker

public IGeneConstraintChecker getConstraintChecker()

Returns:

IGeneConstraintChecker the constraint checker to be used whenever method setAllele(Object a_newValue) is called

Since:

2.0

newGene

public Gene newGene()

Provides an implementation-independent means for creating new Gene instances. The new instance that is created and returned should be setup with any implementation-dependent configuration that this Gene instance is setup with (aside from the actual value, of course). For example, if this Gene were setup with bounds on its value, then the Gene instance returned from this method should also be setup with those same bounds. This is important, as the JGAP core will invoke this method on each Gene in the sample Chromosome in order to create each new Gene in the same respective gene position for a new Chromosome.

It should be noted that nothing is guaranteed about the actual value of the returned Gene and it should therefore be considered to be undefined.

Specified by:

newGene in interface Gene

Returns:

A new Gene instance of the same type and with the same setup as this concrete Gene.

Since:

1.1

compareTo

public int compareTo(java.lang.Object other)

Compares this StringGene with the specified object (which must also be a StringGene) for order, which is determined by the String value of this Gene compared to the one provided for comparison.

Specified by:

compareTo in interface java.lang.Comparable

Parameters:

other - the StringGene to be compared to this StringGene.

Returns:

a negative int, zero, or a positive int as this object is less than, equal to, or greater than the object provided for comparison.

Throws:

java.lang.ClassCastException - if the specified object's type prevents it from being compared to this StringGene.

Since:

1.1

size

public int size()

Specified by:

size in interface Gene

Returns:

the size of the gene, i.e the number of atomic elements. Always 1 for numbers

getMaxLength

public int getMaxLength()

getMinLength

public int getMinLength()

setMinLength

public void setMinLength(int m_minLength)

setMaxLength

public void setMaxLength(int m_maxLength)

getAlphabet

public java.lang.String getAlphabet()

setAlphabet

public void setAlphabet(java.lang.String a_alphabet)

Sets the valid alphabet of the StringGene

Parameters:

a_alphabet - valid aplhabet for allele

Since:

1.1

toString

public java.lang.String toString()

Retrieves a string representation of this StringGene's value that may be useful for display purposes.

Specified by:

toString in interface Gene

Returns:

a string representation of this StringGene's value.

Since:

1.1

equals

public boolean equals(java.lang.Object other)

Compares this Gene with the given object and returns true if the other object is a Gene of this type and has the same value (allele) as this Gene. Otherwise it returns false.

Parameters:

other - the object to compare to this Gene for equality.

Returns:

true if this Gene is equal to the given object, false otherwise.

Since:

1.1

hashCode

public int hashCode()

Retrieves the hash code value for this StringGene.

Returns:

this StringGene's hash code.

Since:

1.1

stringValue

public java.lang.String stringValue()

Retrieves the String value of this Gene, which may be more convenient in some cases than the more general getAllele() method.

Returns:

the String value of this Gene.

Since:

1.1

applyMutation

public void applyMutation(int index,
                          double a_percentage)

Applies a mutation of a given intensity (percentage) onto the atomic element at given index (NumberGenes only have one atomic element)

Specified by:

applyMutation in interface Gene

Parameters:

index - index of atomic element, between 0 and size()-1

a_percentage - percentage of mutation (greater than -1 and smaller than 1).

Since:

1.1