package undofx;

import javafx.beans.value.ObservableBooleanValue;

public interface UndoManager {
    boolean undo();

    boolean redo();

    ObservableBooleanValue undoAvailableProperty();
    boolean isUndoAvailable();

    ObservableBooleanValue redoAvailableProperty();
    boolean isRedoAvailable();

    /**
     * Prevents the next change from being merged with the last one.
     */
    void preventMerge();

    /**
     * Stops listening to change events.
     */
    void close();
}

@@ -100,129 +100,626 @@
     
-boolean undo();%0A%0A    boolean redo();%0A%0A    ObservableBooleanValue undoAvailableProperty();%0A    boolean isUndoAvailable();%0A
+/**%0A     * Undo the most recent change, if there is any change to undo.%0A     * @return %7B@code true%7D if a change was undone, %7B@code false%7D otherwise.%0A     */%0A    boolean undo();%0A%0A    /**%0A     * Redo previously undone change, if there is any change to redo.%0A     * @return %7B@code true%7D if a change was redone, %7B@code false%7D otherwise.%0A     */%0A    boolean redo();%0A%0A    /**%0A     * Indicates whether there is a change that can be undone.%0A     */%0A    ObservableBooleanValue undoAvailableProperty();%0A    boolean isUndoAvailable();%0A%0A    /**%0A     * Indicates whether there is a change that can be redone.%0A     * @return%0A     */
 %0A   
@@ -868,16 +868,18 @@
 h the la
+te
 st one.%0A
@@ -937,20 +937,17 @@
 ops 
-listening to
+observing
  cha

Improve Javadoc.