StateEdit.java (getPresentationName): Docfix.

2003-11-26  Sascha Brawer  <brawer@dandelis.ch>

	* javax/swing/undo/StateEdit.java (getPresentationName): Docfix.
	* javax/swing/undo/AbstractUndoableEdit.java (canUndo, canRedo,
	isSignificant): Likewise.

2003-11-26  Sascha Brawer  <brawer@dandelis.ch>

	* javax/swing/undo/CompoundEdit.java: Re-format, document.
	(inProgress): Set initial value to true.
	(undo, redo, die, canUndo, canRedo): Also call inherited
	implementation; simplify code structure.
	(getPresentationName, getUndoPresentationName,
	getRedoPresentationName): Make behavior dependent on lastEdit.
	(addEdit, isSignificant): Completely re-written.

2003-11-26  Sascha Brawer  <brawer@dandelis.ch>

	* javax/swing/undo/StateEdit.java: Re-format, document.
	(undo, redo): Also call inherited implementation.

2003-11-26  Sascha Brawer  <brawer@dandelis.ch>

	* javax/swing/undo/StateEditable.java: Re-format, document.

2003-11-26  Sascha Brawer  <brawer@dandelis.ch>

	* javax/swing/undo/AbstractUndoableEdit.java: Re-format, document.
	(AbstractUndoableEdit): Initialize hasBeenDone to true.
	(canUndo, canRedo): Simplify.
	(getUndoPresentationName, getRedoPresentationName): Support
	localized message; call getPresentationName() only once.

From-SVN: r73967

1 files changed, 350 insertions, 240 deletions

diff --git a/libjava/javax/swing/undo/CompoundEdit.java b/libjava/javax/swing/undo/CompoundEdit.java
index be612da..12ff2bd 100644
--- a/libjava/javax/swing/undo/CompoundEdit.java
+++ b/libjava/javax/swing/undo/CompoundEdit.java
@@ -1,5 +1,5 @@
-/* AbstractTableModel.java --
-   Copyright (C) 2002 Free Software Foundation, Inc.
+/* CompoundEdit.java -- Combines multiple UndoableEdits.
+   Copyright (C) 2002, 2003 Free Software Foundation, Inc.
 
 This file is part of GNU Classpath.
 
@@ -41,242 +41,352 @@ package javax.swing.undo;
 import java.util.Vector;
 
 /**
- * CompoundEdit
- * @author Andrew Selkirk
+ * An editing action that consists of multiple
+ * <code>UndoableEdits</code>.
+ *
+ * <p>The use of a <code>CompoundEdit</code> is divided in two separate
+ * phases.
+ *
+ * <ol><li>In the first phase, the <code>CompoundEdit</code> is
+ * initialized.  After a new instance of <code>CompoundEdit</code> has
+ * been created, {@link #addEdit(UndoableEdit)} is called for each
+ * element of the compound.  To terminate the initialization phase,
+ * call {@link #end()}.</li>
+ *
+ * <li>In the second phase, the the <code>CompoundEdit</code> can be
+ * used, typically by invoking {@link #undo()} and {@link
+ * #redo()}.</li></ol>
+ *
+ * @author Andrew Selkirk (aselkirk@sympatico.ca)
+ * @author Sascha Brawer (brawer@dandelis.ch)
  */
-public class CompoundEdit extends AbstractUndoableEdit {
-
-	//-------------------------------------------------------------
-	// Variables --------------------------------------------------
-	//-------------------------------------------------------------
-
-	/**
-	 * The collection of UndoableEdits undone/redone en
-	 * masse by this CompoundEdit
-	 */
-	protected	Vector	edits		= new Vector();
-
-	/**
-	 * TODO
-	 */
-	private		boolean	inProgress	= false;
-
-
-	//-------------------------------------------------------------
-	// Initialization ---------------------------------------------
-	//-------------------------------------------------------------
-
-	/**
-	 * Create new Compound Edit
-	 */
-	public CompoundEdit() {
-	} // CompoundEdit()
-
-
-	//-------------------------------------------------------------
-	// Interface: UndoableEdit ------------------------------------
-	//-------------------------------------------------------------
-
-	/**
-	 * addEdit
-	 * @param anEdit TODO
-	 * @returns TODO
-	 */
-	public boolean addEdit(UndoableEdit anEdit) {
-
-		// Variables
-		UndoableEdit	lastEdit;
-
-		if (inProgress == true) {
-
-			// Get Last Edit
-			lastEdit = lastEdit();
-
-			// Check for null
-			if (lastEdit != null) {
-
-				if (lastEdit.addEdit(anEdit) == false) {
-					if (lastEdit.replaceEdit(anEdit) == false) {
-						edits.add(anEdit);
-					}
-				}
-
-			} // if: lastEdit
-
-			return true;
-
-		} else {
-			return false;
-		}
-	} // addEdit()
-
-	/**
-	 * canRedo
-	 * @returns TODO
-	 */
-	public boolean canRedo() {
-		if (isInProgress() == true || super.canRedo() == false) {
-			return false;
-		}
-		return true;
-	} // canRedo()
-
-	/**
-	 * canUndo
-	 * @returns TODO
-	 */
-	public boolean canUndo() {
-		if (isInProgress() == true || super.canUndo() == false) {
-			return false;
-		}
-		return true;
-	} // canUndo()
-
-	/**
-	 * die
-	 */
-	public void die() {
-
-		// Variables
-		int				index;
-		UndoableEdit	current;
-
-		// Loop through all contained UndoableEdits
-		for (index = edits.size() - 1; index >= 0; index--) {
-			current = (UndoableEdit) edits.elementAt(index);
-			current.die();
-		} // for: index
-
-	} // die()
-
-	/**
-	 * end
-	 */
-	public void end() {
-		inProgress = false;
-	} // end()
-
-	/**
-	 * getPresentationName
-	 * @returns TODO
-	 */
-	public String getPresentationName() {
-		if (edits.size() == 0) {
-			return super.getPresentationName();
-		} else {
-			return lastEdit().getPresentationName();
-		}
-	} // getPresentationName()
-
-	/**
-	 * getRedoPresentationName
-	 * @returns TODO
-	 */
-	public String getRedoPresentationName()	{
-		if (edits.size() == 0) {
-			return super.getRedoPresentationName();
-		} else {
-			return lastEdit().getRedoPresentationName();
-		}
-	} // getRedoPresentationName()
-
-	/**
-	 * getUndoPresentationName
-	 * @returns TODO
-	 */
-	public String getUndoPresentationName()	{
-		if (edits.size() == 0) {
-			return super.getUndoPresentationName();
-		} else {
-			return lastEdit().getUndoPresentationName();
-		}
-	} // getUndoPresentationName()
-
-	/**
-	 * isInProgress
-	 * @returns TODO
-	 */
-	public boolean isInProgress() {
-		return inProgress;
-	} // isInProgress()
-
-
-	/**
-	 * isSignigicant
-	 * @returns TODO
-	 */
-	public boolean isSignificant() {
-
-		// Variables
-		int				index;
-		UndoableEdit	current;
-
-		// Check each edit
-		for (index = 0; index < edits.size(); index++) {
-			current = (UndoableEdit) edits.elementAt(index);
-			if (current.isSignificant() == true) {
-				return true;
-			}
-		} // for: index
-
-		return false;
-
-	} // isSignificant()
-
-	/**
-	 * lastEdit
-	 * @returns TODO
-	 */
-	protected UndoableEdit lastEdit() {
-		if (edits.size() == 0) {
-			return null;
-		}
-		return (UndoableEdit) edits.elementAt(edits.size() - 1);
-	} // lastEdit()
-
-	/**
-	 * redo
-	 * @throws CannotRedoException TODO
-	 */
-	public void redo() throws CannotRedoException {
-
-		// Variables
-		int				index;
-		UndoableEdit	current;
-
-		// Loop through all contained UndoableEdits
-		for (index = 0; index < edits.size(); index++) {
-			current = (UndoableEdit) edits.elementAt(index);
-			current.redo();
-		} // for: index
-
-	} // redo()
-
-	/**
-	 * String representation
-	 * @returns String representation
-	 */
-	public String toString() {
-		return null; // TODO
-	} // toString()
-
-	/**
-	 * undo
-	 * @throws CannotUndoException TODO
-	 */
-	public void undo() throws CannotUndoException {
-
-		// Variables
-		int				index;
-		UndoableEdit	current;
-
-		// Loop through all contained UndoableEdits
-		for (index = edits.size() - 1; index >= 0; index--) {
-			current = (UndoableEdit) edits.elementAt(index);
-			current.undo();
-		} // for: index
-
-	} // undo()
-
-
-} // CompoundEdit
+public class CompoundEdit
+  extends AbstractUndoableEdit
+{
+  /**
+   * The <code>UndoableEdit</code>s being combined into a compound
+   * editing action.
+   */
+  protected Vector edits;
+
+
+  /**
+   * Indicates whether the creation of this CompoundEdit is still in
+   * progress. Initially, the value of this flag is
+   * <code>true</code>. The {@link #end()} method changes the flag to
+   * <code>false</code>. 
+   */
+  private boolean inProgress;
+
+
+  /**
+   * Constructs a new CompoundEdit.
+   */
+  public CompoundEdit()
+  {
+    edits = new Vector();
+    inProgress = true;
+  }
+  
+
+  /**
+   * Undoes all edits that are part of of this
+   * <code>CompoundEdit</code>. The compound elements will receive the
+   * <code>undo</code> message in the reverse order of addition.
+   *
+   * @throws CannotUndoException if {@link #canUndo()} returns
+   * <code>false</code>. This can happen if {@link #end()} has not
+   * been called on this <code>CompoundEdit</code>, or if this edit
+   * has already been undone.
+   *
+   * @see #canUndo()
+   * @see #redo()
+   */
+  public void undo()
+    throws CannotUndoException
+  {
+    // AbstractUndoableEdit.undo() will throw a CannotUndoException if
+    // canUndo returns false.
+    super.undo();
+
+    for (int i = edits.size() - 1; i >= 0; i--)
+      ((UndoableEdit) edits.elementAt(i)).undo();
+  }
+
+
+  /**
+   * Redoes all edits that are part of of this
+   * <code>CompoundEdit</code>. The compound elements will receive the
+   * <code>undo</code> message in the same order as they were added.
+   *
+   * @throws CannotRedoException if {@link #canRedo()} returns
+   * <code>false</code>. This can happen if {@link #end()} has not
+   * been called on this <code>CompoundEdit</code>, or if this edit
+   * has already been redone.
+   *
+   * @see #canRedo()
+   * @see #undo()
+   */
+  public void redo()
+    throws CannotRedoException
+  {
+    // AbstractUndoableEdit.redo() will throw a CannotRedoException if
+    // canRedo returns false.
+    super.redo();
+
+    for (int i = 0; i < edits.size(); i++)
+      ((UndoableEdit) edits.elementAt(i)).redo();
+  }
+
+  
+  /**
+   * Returns the the <code>UndoableEdit</code> that was last added to
+   * this compound.
+   */
+  protected UndoableEdit lastEdit()
+  {
+    if (edits.size() == 0)
+      return null;
+    else
+      return (UndoableEdit) edits.elementAt(edits.size() - 1);
+  }
+
+
+  /**
+   * Informs this edit action, and all compound edits, that they will
+   * no longer be used. Some actions might use this information to
+   * release resources such as open files.  Called by {@link
+   * UndoManager} before this action is removed from the edit queue.
+   *
+   * <p>The compound elements will receive the
+   * <code>die</code> message in the reverse order of addition.
+   */
+  public void die()
+  {
+    for (int i = edits.size() - 1; i >= 0; i--)
+      ((UndoableEdit) edits.elementAt(i)).die();
+
+    super.die();
+  }
+
+
+  /**
+   * Incorporates another editing action into this one, thus forming a
+   * combined edit.
+   *
+   * <p>If this edit&#x2019;s {@link #end()} method has been called
+   * before, <code>false</code> is returned immediately. Otherwise,
+   * the {@linkplain #lastEdit() last added edit} is given the
+   * opportunity to {@linkplain UndoableEdit#addEdit(UndoableEdit)
+   * incorporate} <code>edit</code>.  If this fails, <code>edit</code>
+   * is given the opportunity to {@linkplain
+   * UndoableEdit#replaceEdit(UndoableEdit) replace} the last added
+   * edit.  If this fails as well, <code>edit</code> gets added as a
+   * new compound to {@link #edits}.
+   * 
+   * @param edit the editing action being added.
+   *
+   * @return <code>true</code> if <code>edit</code> could somehow be
+   * incorporated; <code>false</code> if <code>edit</code> has not
+   * been incorporated because {@link #end()} was called before.
+   */
+  public boolean addEdit(UndoableEdit edit)
+  {
+    UndoableEdit last;
+
+    // If end has been called before, do nothing.
+    if (!inProgress)
+      return false;
+
+    last = lastEdit();
+
+    // If edit is the very first edit, just add it to the list.
+    if (last == null)
+    {
+      edits.add(edit);
+      return true;
+    }
+
+    // Try to incorporate edit into last.
+    if (last.addEdit(edit))
+      return true;
+
+    // Try to replace last by edit.
+    if (edit.replaceEdit(last))
+    {
+      edits.set(edits.size() - 1, edit);
+      return true;
+    }
+
+    // If everything else has failed, add edit to the list of compound
+    // edits.
+    edits.add(edit);
+    return true;
+  }
+
+
+  /**
+   * Informs this <code>CompoundEdit</code> that its construction
+   * phase has been completed. After this method has been called,
+   * {@link #undo()} and {@link #redo()} may be called, {@link
+   * #isInProgress()} will return <code>false</code>, and all attempts
+   * to {@linkplain #addEdit(UndoableEdit) add further edits} will
+   * fail.
+   */
+  public void end()
+  {
+    inProgress = false;
+  }
+
+
+  /**
+   * Determines whether it would be possible to undo this editing
+   * action. The result will be <code>true</code> if {@link #end()}
+   * has been called on this <code>CompoundEdit</code>, {@link #die()}
+   * has not yet been called, and the edit has not been undone
+   * already.
+   *
+   * @return <code>true</code> to indicate that this action can be
+   * undone; <code>false</code> otherwise.
+   *
+   * @see #undo()
+   * @see #canRedo()
+   */
+  public boolean canUndo()
+  {
+    return !inProgress && super.canUndo();
+  }
+
+
+  /**
+   * Determines whether it would be possible to redo this editing
+   * action. The result will be <code>true</code> if {@link #end()}
+   * has been called on this <code>CompoundEdit</code>, {@link #die()}
+   * has not yet been called, and the edit has not been redone
+   * already.
+   *
+   * @return <code>true</code> to indicate that this action can be
+   * redone; <code>false</code> otherwise.
+   *
+   * @see #redo()
+   * @see #canUndo()
+   */
+  public boolean canRedo()
+  {
+    return !inProgress && super.canRedo();
+  }
+
+
+  /**
+   * Determines whether the initial construction phase of this
+   * <code>CompoundEdit</code> is still in progress.  During this
+   * phase, edits {@linkplain #addEdit(UndoableEdit) may be
+   * added}. After initialization has been terminated by calling
+   * {@link #end()}, {@link #undo()} and {@link #redo()} can be used.
+   *
+   * @return <code>true</code> if the initialization phase is still in
+   * progress; <code>false</code> if {@link #end()} has been called.
+   *
+   * @see #end()
+   */
+  public boolean isInProgress()
+  {
+    return inProgress;
+  }
+
+
+  /**
+   * Determines whether this editing action is significant enough for
+   * being seperately undoable by the user. A typical significant
+   * action would be the resizing of an object. However, changing the
+   * selection in a text document would usually not be considered
+   * significant.
+   *
+   * <p>A <code>CompoundEdit</code> is significant if any of its
+   * elements are significant.
+   */
+  public boolean isSignificant()
+  {
+    for (int i = edits.size() - 1; i >= 0; i--)
+      if (((UndoableEdit) edits.elementAt(i)).isSignificant())
+        return true;
+
+    return false;
+  }
+  
+
+  /**
+   * Returns a human-readable, localized name that describes this
+   * editing action and can be displayed to the user.
+   *
+   * <p>The implementation delegates the call to the {@linkplain
+   * #lastEdit() last added edit action}. If no edit has been added
+   * yet, the inherited implementation will be invoked, which always
+   * returns an empty string.
+   */
+  public String getPresentationName()
+  {
+    UndoableEdit last;
+
+    last = lastEdit();
+    if (last == null)
+      return super.getPresentationName();
+    else
+      return last.getPresentationName();
+  }
+
+
+  /**
+   * Calculates a localized message text for presenting the undo
+   * action to the user.
+   *
+   * <p>The implementation delegates the call to the {@linkplain
+   * #lastEdit() last added edit action}. If no edit has been added
+   * yet, the {@linkplain
+   * AbstractUndoableEdit#getUndoPresentationName() inherited
+   * implementation} will be invoked.
+   */
+  public String getUndoPresentationName()
+  {
+    UndoableEdit last;
+
+    last = lastEdit();
+    if (last == null)
+      return super.getUndoPresentationName();
+    else
+      return last.getUndoPresentationName();
+  }
+
+
+  /**
+   * Calculates a localized message text for presenting the redo
+   * action to the user.
+   *
+   * <p>The implementation delegates the call to the {@linkplain
+   * #lastEdit() last added edit action}. If no edit has been added
+   * yet, the {@linkplain
+   * AbstractUndoableEdit#getRedoPresentationName() inherited
+   * implementation} will be invoked.
+   */
+  public String getRedoPresentationName()
+  {
+    UndoableEdit last;
+
+    last = lastEdit();
+    if (last == null)
+      return super.getRedoPresentationName();
+    else
+      return last.getRedoPresentationName();
+  }
+  
+  
+  /**
+   * Calculates a string that may be useful for debugging.
+   */
+  public String toString()
+  {
+    return super.toString()
+      + " inProgress: " + inProgress
+      + " edits: " + edits;
+  }
+}