Some improvements to javadoc have identified a number of missing javadoc tags and comments in the desktop module.
These are mostly in AWT classes although there are also a few in javax/swing/text/GapVector.java. I'll leave it up to the fixer to decide whether to split those off into a separate bug.

/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/javax/swing/text/GapVector.java:82: warning: no @return
    protected final Object getArray() {
                           ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/javax/swing/text/GapVector.java:96: warning: no @return
    protected final int getGapEnd() {
                        ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/javax/swing/text/GapVector.java:89: warning: no @return
    protected final int getGapStart() {
                        ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/javax/swing/text/GapVector.java:132: warning: no @param for addSize
    protected void replace(int position, int rmSize, Object addItems, int addSize) {
                   ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/javax/swing/text/GapVector.java:71: warning: no @param for len
    protected abstract Object allocateArray(int len);
                              ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/javax/swing/text/GapVector.java:71: warning: no @return
    protected abstract Object allocateArray(int len);
                              ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/javax/swing/text/GapVector.java:76: warning: no @return
    protected abstract int getArrayLength();
                           ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/javax/swing/text/GapVector.java:224: warning: no @param for newSize
    protected void shiftEnd(int newSize) {
                   ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/javax/swing/text/GapVector.java:255: warning: no @param for newGapStart
    protected void shiftGap(int newGapStart) {
                   ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/javax/swing/text/GapVector.java:284: warning: no @param for newGapStart
    protected void shiftGapStartDown(int newGapStart) {
                   ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/javax/swing/text/GapVector.java:296: warning: no @param for newGapEnd
    protected void shiftGapEndUp(int newGapEnd) {
                   ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/applet/Applet.java:109: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/applet/Applet.java:109: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/AWTEvent.java:90: warning: no comment
    private byte[] bdata;
                   ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/AWTKeyStroke.java:80: warning: no comment
    private char keyChar = KeyEvent.CHAR_UNDEFINED;
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/AWTKeyStroke.java:81: warning: no comment
    private int keyCode = KeyEvent.VK_UNDEFINED;
                ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/AWTKeyStroke.java:82: warning: no comment
    private int modifiers;
                ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/AWTKeyStroke.java:83: warning: no comment
    private boolean onKeyRelease;
                    ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Button.java:482: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Button.java:482: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Button.java:457: warning: no @throws for java.io.IOException
    private void writeObject(ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Button.java:436: warning: no comment
    private int buttonSerializedDataVersion = 1;
                ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CardLayout.java:564: warning: no @param for s
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CardLayout.java:564: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CardLayout.java:564: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CardLayout.java:595: warning: no @param for s
    private void writeObject(ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CardLayout.java:595: warning: no @throws for java.io.IOException
    private void writeObject(ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CardLayout.java:113: warning: no description for @serialField
     * @serialField hgap int
       ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CardLayout.java:114: warning: no description for @serialField
     * @serialField vgap int
       ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CardLayout.java:115: warning: no description for @serialField
     * @serialField vector Vector
       ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CardLayout.java:116: warning: no description for @serialField
     * @serialField currentCard int
       ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CardLayout.java:74: warning: no comment
    class Card implements Serializable {
    ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Checkbox.java:655: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Checkbox.java:655: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Checkbox.java:630: warning: no @throws for java.io.IOException
    private void writeObject(ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Checkbox.java:609: warning: no comment
    private int checkboxSerializedDataVersion = 1;
                ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CheckboxMenuItem.java:475: warning: no comment
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CheckboxMenuItem.java:454: warning: no @throws for java.io.IOException
    private void writeObject(ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/CheckboxMenuItem.java:433: warning: no comment
    private int checkboxMenuItemSerializedDataVersion = 1;
                ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Choice.java:707: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Choice.java:707: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Choice.java:682: warning: no @throws for java.io.IOException
    private void writeObject(ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Choice.java:661: warning: no comment
    private int choiceSerializedDataVersion = 1;
                ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Component.java:8980: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Component.java:8980: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Component.java:8944: warning: no @throws for java.io.IOException
    private void writeObject(ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Component.java:8335: warning: no comment
    private boolean autoFocusTransferOnDisposal = true;
                    ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Component.java:719: warning: no comment
    boolean isPacked = false;
            ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/ComponentOrientation.java:204: warning: no comment
    private int orientation;
                ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Container.java:3721: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Container.java:3721: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Container.java:3683: warning: no @throws for java.io.IOException
    private void writeObject(ObjectOutputStream s) throws IOException {
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/ContainerOrderFocusTraversalPolicy.java:66: warning: no comment
    private final int BACKWARD_TRAVERSAL = 1;
                      ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/ContainerOrderFocusTraversalPolicy.java:65: warning: no comment
    private final int FORWARD_TRAVERSAL = 0;
                      ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/ContainerOrderFocusTraversalPolicy.java:73: warning: no comment
    private boolean implicitDownCycleTraversal = true;
                    ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Dialog.java:1590: warning: no comment
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/FileDialog.java:603: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/FileDialog.java:603: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/FileDialog.java:85: warning: no comment
    String dir;
           ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/FileDialog.java:96: warning: no comment
    String file;
           ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/FileDialog.java:129: warning: no comment
    FilenameFilter filter;
                   ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/FileDialog.java:75: warning: no comment
    int mode;
        ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/FlowLayout.java:666: warning: no @param for stream
    private void readObject(ObjectInputStream stream)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/FlowLayout.java:666: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream stream)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/FlowLayout.java:666: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream stream)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Font.java:1914: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(java.io.ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Font.java:1914: warning: no @throws for java.io.IOException
    private void readObject(java.io.ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Font.java:1891: warning: no @throws for java.io.IOException
    private void writeObject(java.io.ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Frame.java:1222: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Frame.java:1186: warning: no @throws for java.io.IOException
    private void writeObject(ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Frame.java:359: warning: no comment
    Vector<Window> ownedWindows;
                   ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Frame.java:350: warning: no comment
    private int state = NORMAL;
                ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:54: warning: no comment
    short[] baselineType; /* The type of baseline for a particular
            ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:49: warning: no comment
    boolean hasBaseline; /* Whether or not baseline layout has been
            ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:43: warning: no comment
    int width, height; /* number of cells: horizontal and vertical */
               ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:57: warning: no comment
    int[] maxAscent; /* Max ascent (baseline). */
          ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:58: warning: no comment
    int[] maxDescent; /* Max descent (height - baseline) */
          ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:46: warning: no comment
    int[] minHeight; /* largest minHeight in each row */
          ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:45: warning: no comment
    int[] minWidth; /* largest minWidth in each column */
          ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:44: warning: no comment
    int startx, starty; /* starting point for layout */
        ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:44: warning: no comment
    int startx, starty; /* starting point for layout */
                ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:47: warning: no comment
    double[] weightX; /* largest weight in each column */
             ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:48: warning: no comment
    double[] weightY; /* largest weight in each row */
             ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/GridBagLayoutInfo.java:43: warning: no comment
    int width, height; /* number of cells: horizontal and vertical */
        ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/MediaTracker.java:927: warning: no comment
class ImageMediaEntry extends MediaEntry implements ImageObserver,
^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Label.java:163: warning: no @param for s
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Label.java:163: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Label.java:163: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/List.java:1276: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/List.java:1276: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/List.java:1243: warning: no @throws for java.io.IOException
    private void writeObject(ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/List.java:1536: warning: no comment
            private int indexInParent;
                         ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/List.java:1535: warning: no comment
            private List parent;
                         ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Menu.java:550: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Menu.java:550: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/Menu.java:533: warning: no @throws for java.io.IOException
    private void writeObject(java.io.ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/MenuBar.java:451: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/MenuBar.java:451: warning: no @throws for java.io.IOException
    private void readObject(ObjectInputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/MenuBar.java:434: warning: no @throws for java.io.IOException
    private void writeObject(java.io.ObjectOutputStream s)
                 ^
/Volumes/J2GWork/jdk/jdk.ref/open/src/java.desktop/share/classes/java/awt/MenuComponent.java:448: warning: no @throws for java.lang.ClassNotFoundException
    private void readObject(ObjectInputStream s)
                 ^
100 warnings