dk.rode.thesis.singleton
Class MutatedSimpsonsFamilySequence

java.lang.Object
  dk.rode.thesis.meta.model.AbstractSequence<E>
      dk.rode.thesis.meta.model.ArraySequence<String>
          dk.rode.thesis.singleton.SimpsonsFamilySequence
              dk.rode.thesis.singleton.MutatedSimpsonsFamilySequence

All Implemented Interfaces:

Sequence<String>, Copyable<Sequence<String>>, StrictCopyable<Sequence<String>>, Stringable<Sequence<String>>, Cloneable

public final class MutatedSimpsonsFamilySequence
extends SimpsonsFamilySequence
implements Cloneable

A mutated Simpsons family sequence is a sequence representing a random mutated sub-set of the primary family members in the one and only The Simpsons family.

This class can be sub-classed.

Implementation notes:
Even though the super class SimpsonsFamilySequence is a singleton class, this class is not. Creation and copying works like it does for any other non-singleton sequence. This sequence is also cloneable, but will still not create additional SimpsonsFamilySequence instances.

It would in fact be possible to create SimpsonsFamilySequence instances from the MutatedSimpsonsFamilySequence(int) and MutatedSimpsonsFamilySequence(MutatedSimpsonsFamilySequence) constructors without the call to a super-constructor, i.e. using new. A caller cannot determine how the super-class constructor is invoked from a sub-class, only from where. Hence, any singleton type that allows sub-classing has to trust the sub-classes to some extent. However, it is not possible even for sub-classes to invoke the super constructor from other places than constructors. The evilCreation() method is test method that will try and create a SimpsonsFamilySequence, but will fail because it is not a constructor.

Even though this class references static fields in SimpsonsFamilySequence class, it will not cause the SimpsonsFamilySequence singleton instance to be created.

Author:

Gunni Rode / rode.dk

Nested Class Summary

Nested classes/interfaces inherited from interface dk.rode.thesis.meta.model.Sequence

Sequence.State

Field Summary

Fields inherited from class dk.rode.thesis.singleton.SimpsonsFamilySequence

members, SIZE

Fields inherited from class dk.rode.thesis.meta.model.ArraySequence

elements, index

Fields inherited from class dk.rode.thesis.meta.model.AbstractSequence

state

Constructor Summary

MutatedSimpsonsFamilySequence()
No-arg constructor.

MutatedSimpsonsFamilySequence(int members)
Constructor.

MutatedSimpsonsFamilySequence(MutatedSimpsonsFamilySequence sequence)
Copy constructor.

Method Summary

MutatedSimpsonsFamilySequence	clone() Returns a clone of this sequence.
MutatedSimpsonsFamilySequence	copy() Returns this instance.
SimpsonsFamilySequence	evilCreation() Tries to create a SimpsonsFamilySequence instance based on an off-limit constructor.
private static String[]	getMutatedMembers(int members) Returns a mutated sub-set of the primary family members in The Simpsons family of size members.

Methods inherited from class dk.rode.thesis.singleton.SimpsonsFamilySequence

equals, getFamily, hashCode

Methods inherited from class dk.rode.thesis.meta.model.ArraySequence

bounded, consistent, current, next, reset, size, unique

Methods inherited from class dk.rode.thesis.meta.model.AbstractSequence

getStringablePolicy, state, toString, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface dk.rode.thesis.meta.model.Sequence

state

Methods inherited from interface dk.rode.thesis.strategy.Stringable

getStringablePolicy, toString

Constructor Detail

MutatedSimpsonsFamilySequence

public MutatedSimpsonsFamilySequence()

No-arg constructor.

Half the members of The Simpsons family will be included in this mutated sequence.

MutatedSimpsonsFamilySequence

public MutatedSimpsonsFamilySequence(int members)

Constructor.

The number of members of the The Simpsons family included in this sequence is specified by members.

Parameters:

members - The members; must be within [1, SimpsonsFamilySequence.SIZE].

Throws:

IllegalArgumentException - If members is illegal.

MutatedSimpsonsFamilySequence

public MutatedSimpsonsFamilySequence(MutatedSimpsonsFamilySequence sequence)

Copy constructor.

Parameters:

sequence - The sequence to copy; cannot be null.

Throws:

NullPointerException - If sequence is null.

Method Detail

clone

public MutatedSimpsonsFamilySequence clone()
                                    throws CloneNotSupportedException

Returns a clone of this sequence.

Overrides:

clone in class Object

Returns:

A clone of this sequence; never null.

Throws:

CloneNotSupportedException - If the cloning fails.

copy

public MutatedSimpsonsFamilySequence copy()

Description copied from class: SimpsonsFamilySequence

Returns this instance.

Specified by:

copy in interface Sequence<String>

Specified by:

copy in interface Copyable<Sequence<String>>

Overrides:

copy in class SimpsonsFamilySequence

Returns:

This instance; never null.

evilCreation

public SimpsonsFamilySequence evilCreation()
                                    throws SingletonError

Tries to create a SimpsonsFamilySequence instance based on an off-limit constructor. Doing so should cause a SingletonError to be thrown! If not, it constitutes an internal error and the singleton invariant is broken.

Returns:

Should never return.

Throws:

SingletonError - Always thrown.

getMutatedMembers

private static final String[] getMutatedMembers(int members)

Returns a mutated sub-set of the primary family members in The Simpsons family of size members.

Parameters:

members - The members; must be within [1, SimpsonsFamilySequence.SIZE].

Returns:

The sub-set; never null, and never empty.

Throws:

IllegalArgumentException - If members is illegal.