Name: auR10023 Date: 11/17/2000


  
The next methods of javax.swing.LayoutFocusTraversalPolicy:

    getComponentAfter(Container, Component)
    getComponentBefore(Container, Component)
    getFirstComponent(Container)
    getLastComponent(Container)
  
incorrectly raise NullPointerException when Container is null.
  
But javadoc for these methods states:
  
 getComponentAfter(), getComponentBefore()
  
...
Throws:
          IllegalArgumentException - if focusCycleRoot is not a focus cycle root of
          aComponent, or if either focusCycleRoot or aComponent is null
...
  
  
 getFirstComponent() and getLastComponent()

...
Throws:
          IllegalArgumentException - if focusCycleRoot is null
...


----Test.java------
import javax.swing.*;
import java.awt.*;

public class Test {
    public static void main (String[] args) {
        LayoutFocusTraversalPolicy policy = new LayoutFocusTraversalPolicy();
        Component comp = new JTextField();
        try {
            policy.getComponentAfter(null, comp);
        } catch(IllegalArgumentException e) {
            System.out.println("IllegalArgumentException was obtained");
        } catch(NullPointerException e) {
            System.out.println("NullPointerException was obtained");
        }
    }
}

-----Output--------

NullPointerException was obtained

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