The class org.pentaho.reportdesigner.lib.client.undo.Undo is used to collect changes of the report model on an undo stack and is used to undo/redo the changes on the stack.
The main-method of the Undo class contains some sample code.
The commands UndoCommand and RedoCommand are used to revert/redo changes.
The undo contains the changes as a liked linked list of UndoEntry objects.
An UndoListener can be added to listen for changes.
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