org.refcodes.command

Interface Undoable<CTX,RET,E extends Exception>

Type Parameters:

CTX - The context type to use, can by any Component, service or POJO.

RET - The return type of the Undoable's proceedings.

E - The exception type of the Undoable's erroneous termination.

All Superinterfaces:

Command<CTX,RET,E>

All Known Implementing Classes:

AbstractUndoable

public interface Undoable<CTX,RET,E extends Exception>
extends Command<CTX,RET,E>

An Undoable is a Command) which also provides means to undo its operation applied before. The Undoable is created by a client (e.g. the business logic) and passed to something like a command-bus or command-processor for execution.

Method Summary

Modifier and Type	Method and Description
boolean	isUndoable(CTX aContext) This method determines whether the Undoable can undo the work it has done.
void	undo(CTX aContext) This method tries to undo the Undoable in case it was successfully executed.

Methods inherited from interface org.refcodes.command.Command

execute

Method Detail

isUndoable

boolean isUndoable(CTX aContext)

This method determines whether the Undoable can undo the work it has done.

Parameters:

aContext - The target object which is used by the Undoable to do its Undoable.

Returns:

True if undoable.

undo

void undo(CTX aContext)
   throws NotUndoableRuntimeException,
          UnsupportedOperationException

This method tries to undo the Undoable in case it was successfully executed. Test via isUndoable(Object) beforehand to see whether a call to undo(Object) can be applied.

Parameters:

aContext - The target object which is used by the Undoable to do its Undoable.

Throws:

NotUndoableRuntimeException - Thrown in case the performed operation cannot be undone, or no operation as been done before by this Undoable.

UnsupportedOperationException - Thrown in case the Undoable does not provide undo facilities.