dk.rode.thesis.factorymethod
Class EvilSequenceCommandCreator<E>

java.lang.Object
  dk.rode.thesis.factorymethod.CommandCreator<E,Sequence.State>
      dk.rode.thesis.factorymethod.SequenceCommandCreator<E>
          dk.rode.thesis.factorymethod.EvilSequenceCommandCreator<E>

Type Parameters:

E - The type of values delivered by created commands (and thus sequences).

@Participant(value="ConcreteCreator")
public class EvilSequenceCommandCreator<E>
extends SequenceCommandCreator<E>

An evil sequence command creator is a test creator that flips the functionality offered by the sequence command creator, and may decide to return a new evil command as a default command.

This creator can create the following commands based on the supplied internal sequence state:

• Sequence.State.NORMAL: creates a new ResetCommand instance.

• Sequence.State.RESET: creates a new NextCommand instance.

• Otherwise a NullCommand or or an EvilCommand is returned.

Notice that the regular commands are flipped based on the supplied state!

An evil sequence command creator is stateless and thread-safe.

Implementation notes:
By throwing exceptions in the factory methods, we test the full functionality of the CommandCreator.getCommand(Sequence, Object) method.

Author:

Gunni Rode / rode.dk

Constructor Summary

EvilSequenceCommandCreator()
No-arg constructor.

Method Summary

protected Command<E>	create(Sequence<E> sequence, Sequence.State state) Factory method to create a new command of the type specified by the token supplied as token.
protected EvilCommand<E>	createDefault(Sequence<E> sequence) Factory method to create a new default command in case the normal command creation failed.

Methods inherited from class dk.rode.thesis.factorymethod.CommandCreator

equals, getCommand, hashCode, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

EvilSequenceCommandCreator

public EvilSequenceCommandCreator()

No-arg constructor.

Method Detail

create

protected Command<E> create(Sequence<E> sequence,
                            Sequence.State state)
                     throws Exception

Description copied from class: CommandCreator

Factory method to create a new command of the type specified by the token supplied as token.

The sequence set as the receiver is supplied as sequence.

Overrides:

create in class SequenceCommandCreator<E>

Parameters:

sequence - The sequence; never null.

state - The token identifying the type of command to create; can be null.

Returns:

The corresponding command, or null if no such command could be created. If null is returned, a default (on null) command is returned by CommandCreator.getCommand(Sequence, Object).

Throws:

Exception - If the creation fails; if so, a default (or null) command will be returned by getCommand.

See Also:

CommandCreator.createDefault(Sequence)

createDefault

protected EvilCommand<E> createDefault(Sequence<E> sequence)
                                throws Exception

Description copied from class: CommandCreator

Factory method to create a new default command in case the normal command creation failed.

Overrides:

createDefault in class CommandCreator<E,Sequence.State>

Parameters:

sequence - The sequence; never null.

Returns:

A new default command; if null is returned, a null command is returned by CommandCreator.getCommand(Sequence, Object). This implementation returns a new NullCommand.

Throws:

Exception - If the creation fails; if so, a null command will be returned by getCommand.