We are seeing unexpected/undesirable behavior when using a Swing InputVerifier. The following demo application has an InputVerifier associated with a JTextField. It also has a JComboBox and a JTable to show the interaction of an InputVerifier with components other than JTextField. The InputVerifier warns the user with a modal message box when they have typed more than 3 letters in the JTextField.

If I attempt to run it against 1.4-beta3, I get a stack overflow in attempting to open the JOptionPane from the shouldYieldFocus implementation.

java -version
java version "1.4.0-rc"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-rc-b88)
Java HotSpot(TM) Client VM (build 1.4.0-rc-b88, mixed mode)

For instance,

-- Run InputVerifierTest
-- Type five characters in the JTextField.
-- Click on the JComboBox.
-- You see the following error

java.lang.StackOverflowError
        at java.awt.Component.getToolkitImpl(Component.java:823)
        at java.awt.Component.getToolkitImpl(Component.java:827)
        at java.awt.Component.getToolkitImpl(Component.java:827)
        at java.awt.Component.getToolkitImpl(Component.java:827)
        at java.awt.Component.getToolkitImpl(Component.java:827)
        at java.awt.Component.getToolkitImpl(Component.java:827)
        at java.awt.Component.getToolkitImpl(Component.java:827)
        at java.awt.Component.getToolkitImpl(Component.java:827)
        at java.awt.Component.getToolkitImpl(Component.java:827)
        at java.awt.Component.getToolkit(Component.java:813)
        at java.awt.Component.addNotify(Component.java:5363)
        at java.awt.Container.addNotify(Container.java:1855)
        at javax.swing.JComponent.addNotify(JComponent.java:4273)
        at java.awt.Container.addNotify(Container.java:1862)
        at javax.swing.JComponent.addNotify(JComponent.java:4273)
        at java.awt.Container.addNotify(Container.java:1862)
        at javax.swing.JComponent.addNotify(JComponent.java:4273)
        at java.awt.Container.addNotify(Container.java:1862)
        at javax.swing.JComponent.addNotify(JComponent.java:4273)
        at java.awt.Container.addNotify(Container.java:1862)
        at javax.swing.JComponent.addNotify(JComponent.java:4273)
        at java.awt.Container.addNotify(Container.java:1862)
        at javax.swing.JComponent.addNotify(JComponent.java:4273)
        at java.awt.Container.addNotify(Container.java:1862)
        at javax.swing.JComponent.addNotify(JComponent.java:4273)
        at java.awt.Container.addNotify(Container.java:1862)
        at javax.swing.JComponent.addNotify(JComponent.java:4273)
        at javax.swing.JRootPane.addNotify(JRootPane.java:661)
        at java.awt.Container.addNotify(Container.java:1862)
        at java.awt.Window.addNotify(Window.java:398)
        at java.awt.Dialog.addNotify(Dialog.java:389)


I have attached the complete stack trace in the attachments section.