Class MVCCommand

Object
   |
   +--GrvObject
         |
         +--MVCCommand

Direct Known Subclasses:

MVCAJAXReplyCmd, EDOHolderCloseWindowIfSavedCmd, EDOHolderSelectCmd, EDOHolderCancelAllChangesCmd, EDOCmd, MVCScalarEditCmd, EDOHolderSaveAllChangesCmd, EDOHolderSelectInitialCmd

class MVCCommand

extends GrvObject

This class acts as the abstract base class for each Command (ala Command design pattern).

 Subclasses of MVCCommand should define/override:
  (1) the constructor to load the do/undo/redo context data
      which should set the "valid" attribute to a negative
      number if the command cant properly be initiated. 
  (2) the doit() method which executes the command
  (3) the undo() method which "rolls back" the command
  (4) the redo() method which "un-rolls-back" the command
  (5) canUndo property if this cmd is only meant for mutex

 FYI, REDO would be different than DO, for example, in the case
 that DO had to do a database search to get a value, but REDO
 could simply use that saved value without re-searching for it.

- konstructor()

Field Detail

NextID

<static> Object NextID

MVCCommand

MVCCommand()

Version: 2.0

Author: Bruce Wallace (PolyGlotInc.com)
See:
- konstructor()

details

String details()

return details of this command for user viewing

doit

void doit()

"Do command" logic

DOIT

void DOIT()

"DO" this command if in the proper state.

isInvalid

boolean isInvalid()

return true iff this command should not even be started

konstructor

void konstructor( optName, <String> optErrMsg )

Parameters:
optErrMsg - if not null then cancel this cmd
cmdDesc - general description of this command

redo

void redo()

"command REDO" logic. Default is to just call doit()

REDO

void REDO()

"REDO" this command if in the proper state.

syncDo

void syncDo( methodName )

synchronized call with global view blocking

syncDoIt

void syncDoIt()

synchronized this.DOIT()

syncReDo

void syncReDo()

synchronized this.REDO()

syncUnDo

void syncUnDo()

synchronized this.UNDO()

toString

String toString()

return THIS formatted as string

undo

void undo()

"command UNDO" logic

UNDO

void UNDO()

"UNDO" this command if in the proper state.