Package org.eclipse.emf.common.command

Class BasicCommandStack

java.lang.Object
org.eclipse.emf.common.command.BasicCommandStack
All Implemented Interfaces:
CommandStack
public class BasicCommandStack extends Object implements CommandStack
A basic and obvious implementation of an undoable stack of commands. See Command for more details about the command methods that this implementation uses.

  • Field Details

    • commandList

      protected List<Command> commandList
      The list of commands.

    • top

      protected int top
      The current position within the list from which the next execute, undo, or redo, will be performed.

    • mostRecentCommand

      protected Command mostRecentCommand
      The command most recently executed, undone, or redone.

    • listeners

      protected Collection<CommandStackListener> listeners
      The CommandStackListeners.

    • saveIndex

      protected int saveIndex
      The value of top when saveIsDone() is called.

  • Constructor Details

    • BasicCommandStack

      public BasicCommandStack()
      Creates a new empty instance.

  • Method Details

    • execute

      public void execute(Command command)
      Description copied from interface: CommandStack
      Clears any redoable commands not yet redone, adds the command, and then executes the command.
      Specified by:
      execute in interface CommandStack
      Parameters:
      command - the command to execute.

    • canUndo

      public boolean canUndo()
      Description copied from interface: CommandStack
      Returns whether the top command on the stack can be undone.
      Specified by:
      canUndo in interface CommandStack
      Returns:
      whether the top command on the stack can be undone.

    • undo

      public void undo()
      Description copied from interface: CommandStack
      Moves the top of the stack down, undoing what was formerly the top command.
      Specified by:
      undo in interface CommandStack

    • canRedo

      public boolean canRedo()
      Description copied from interface: CommandStack
      Returns whether there are commands past the top of the stack that can be redone.
      Specified by:
      canRedo in interface CommandStack
      Returns:
      whether there are commands past the top of the stack that can be redone.

    • redo

      public void redo()
      Description copied from interface: CommandStack
      Moves the top of the stack up, redoing the new top command.
      Specified by:
      redo in interface CommandStack

    • flush

      public void flush()
      Description copied from interface: CommandStack
      Disposes all the commands in the stack.
      Specified by:
      flush in interface CommandStack

    • getUndoCommand

      public Command getUndoCommand()
      Description copied from interface: CommandStack
      Returns the command that will be undone if CommandStack.undo() is called.
      Specified by:
      getUndoCommand in interface CommandStack
      Returns:
      the command that will be undone if CommandStack.undo() is called.

    • getRedoCommand

      public Command getRedoCommand()
      Description copied from interface: CommandStack
      Returns the command that will be redone if CommandStack.redo() is called.
      Specified by:
      getRedoCommand in interface CommandStack
      Returns:
      the command that will be redone if CommandStack.redo() is called.

    • getMostRecentCommand

      public Command getMostRecentCommand()
      Description copied from interface: CommandStack
      Returns the command most recently executed, undone, or redone.
      Specified by:
      getMostRecentCommand in interface CommandStack
      Returns:
      the command most recently executed, undone, or redone.

    • addCommandStackListener

      public void addCommandStackListener(CommandStackListener listener)
      Description copied from interface: CommandStack
      Adds a listener to the command stack, which will be notified whenever a command has been processed on the stack.
      Specified by:
      addCommandStackListener in interface CommandStack
      Parameters:
      listener - the listener to add.

    • removeCommandStackListener

      public void removeCommandStackListener(CommandStackListener listener)
      Description copied from interface: CommandStack
      Removes a listener from the command stack.
      Specified by:
      removeCommandStackListener in interface CommandStack
      Parameters:
      listener - the listener to remove.

    • notifyListeners

      protected void notifyListeners()
      This is called to ensure that CommandStackListener.commandStackChanged(java.util.EventObject) is called for each listener.

    • handleError

      protected void handleError(Exception exception)
      Handles an exception thrown during command execution by logging it with the plugin.

    • saveIsDone

      public void saveIsDone()
      Called after a save has been successfully performed.

    • isSaveNeeded

      public boolean isSaveNeeded()
      Returns whether the model has changes since saveIsDone() was call the last.
      Returns:
      whether the model has changes since saveIsDone was call the last.