Using the Undo Framework with Swing Text Components : Redo Undo « Swing « Java Tutorial

1. Java Tutorial
2. Swing
3. Redo Undo

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.event.ActionEvent;

import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JToolBar;
import javax.swing.UIManager;
import javax.swing.undo.CannotRedoException;
import javax.swing.undo.CannotUndoException;
import javax.swing.undo.UndoManager;

class UndoManagerHelper {

  public static Action getUndoAction(UndoManager manager, String label) {
    return new UndoAction(manager, label);
  }

  public static Action getUndoAction(UndoManager manager) {
    return new UndoAction(manager, (String) UIManager.get("AbstractUndoableEdit.undoText"));
  }

  public static Action getRedoAction(UndoManager manager, String label) {
    return new RedoAction(manager, label);
  }

  public static Action getRedoAction(UndoManager manager) {
    return new RedoAction(manager, (String) UIManager.get("AbstractUndoableEdit.redoText"));
  }

  private abstract static class UndoRedoAction extends AbstractAction {
    UndoManager undoManager = new UndoManager();

    String errorMessage = "Cannot undo";

    String errorTitle = "Undo Problem";

    protected UndoRedoAction(UndoManager manager, String name) {
      super(name);
      undoManager = manager;
    }

    public void setErrorMessage(String newValue) {
      errorMessage = newValue;
    }

    public void setErrorTitle(String newValue) {
      errorTitle = newValue;
    }

    protected void showMessage(Object source) {
      if (source instanceof Component) {
        JOptionPane.showMessageDialog((Component) source, errorMessage, errorTitle,
            JOptionPane.WARNING_MESSAGE);
      } else {
        System.err.println(errorMessage);
      }
    }
  }

  public static class UndoAction extends UndoRedoAction {
    public UndoAction(UndoManager manager, String name) {
      super(manager, name);
      setErrorMessage("Cannot undo");
      setErrorTitle("Undo Problem");
    }

    public void actionPerformed(ActionEvent actionEvent) {
      try {
        undoManager.undo();
      } catch (CannotUndoException cannotUndoException) {
        showMessage(actionEvent.getSource());
      }
    }
  }

  public static class RedoAction extends UndoRedoAction {
    public RedoAction(UndoManager manager, String name) {
      super(manager, name);
      setErrorMessage("Cannot redo");
      setErrorTitle("Redo Problem");
    }

    public void actionPerformed(ActionEvent actionEvent) {
      try {
        undoManager.redo();
      } catch (CannotRedoException cannotRedoException) {
        showMessage(actionEvent.getSource());
      }
    }
  }
}

public class UndoSample {
  public static void main(String args[]) {
    JFrame frame = new JFrame("Undo Sample");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JTextArea textArea = new JTextArea();
    JScrollPane scrollPane = new JScrollPane(textArea);

    UndoManager manager = new UndoManager();
    textArea.getDocument().addUndoableEditListener(manager);

    JToolBar toolbar = new JToolBar();
    JButton undoButton = new JButton(UndoManagerHelper.getUndoAction(manager));
    toolbar.add(undoButton);
    JButton redoButton = new JButton(UndoManagerHelper.getRedoAction(manager));
    toolbar.add(redoButton);
    frame.add(toolbar, BorderLayout.NORTH);
    frame.add(scrollPane, BorderLayout.CENTER);
    frame.setSize(300, 150);
    frame.setVisible(true);
  }
}

14.113.Redo Undo
	14.113.1.	Undo Editor
	14.113.2.	Using the Undo Framework with Swing Text Components
	14.113.3.	Undoable Drawing
	14.113.4.	Adding Undo and Redo to a Text Component
	14.113.5.	Bind the undo action to ctl-Z
	14.113.6.	Create a redo action and add it to the text component (JTextComponent)
	14.113.7.	Listen for undo and redo events
	14.113.8.	Create an undo action and add it to the text component