Name: sdC67446 Date: 10/25/99


The method
    protected JButton createActionComponent(Action a)
of class
    javax.swing.JToolBar
throws undefined NullPointerException if 'a' == null.

The other similar methods:
  AbstractButton.configurePropertiesFromAction(Action a)
  AbstractButton.createActionPropertyChangeListener(Action a)
  JRadioButton.createActionPropertyChangeListener(Action a)
  JRadioButton.configurePropertiesFromAction(Action a)

accept input null action and set the values:
  1) getText()
  2) getIcon()
  3) getToolTipText()
  4) isEnabled()

by default.
The documentation for these methods clarify the null-reaction.

It is inconsistency in the JToolBar.createActionComponent(Action).

The doc says:
------------------------------------------------------------
protected JButton createActionComponent(Action a)

      Factory method which creates the JButton for Actions added to
      the JToolBar.
      Parameters:
            a - the Action for the button to be added
      See Also:
            Action

demo test:
--------------------------------------------------
import javax.swing.*;

public class Test extends JToolBar {

    public JButton createActionComponent(Action a) {
        return super.createActionComponent(a);
    }

    public static void main(String argv[]) {
        new Test().createActionComponent(null);
    }
}

output:
--------------------------------------------------
Exception in thread "main" java.lang.NullPointerException
        at javax.swing.JToolBar.createActionComponent(JToolBar.java:444)
        at Test.createActionComponent(Test.java:6)
        at Test.main(Test.java:11)
--------------------------------------------------
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