Name: apR10100 Date: 02/06/2002



Methods:

Frame.setTitle incorrectly and
inconsistently handles null as parameter.

JDK1.4 spec states:

------------------
public String getTitle()
Gets the title of the frame. The title is displayed in the frame's border.

Returns:
the title of this frame, or an empty string ("") if this frame doesn't have a title.

...

public void setTitle(String title)
Sets the title for this frame to the specified string.
...
--------------------------------------------------------------------------------

Handling of null is not specified and should be default (throwing NPE).
getTitle should never return null - it should be some String, possibly
empty.

However jdk1.4 takes null as parameter for setTitle without any
exception and returns null from getTitle() after that:

--------- TestTitle.java
import java.awt.*;

public class TestTitle {

  public static void main (String [] args) {
    
        Frame f = new Frame();
        f.show();
    
        try {
            f.setTitle(null);
            System.out.println("Unexpectedly set title to: '"+f.getTitle()+"'");
        } catch (NullPointerException npe) {
           npe.printStackTrace();
        } finally {
            f.dispose();
        }
    }

--------- Output
3,~/tmp;
/set/java/jdk1.4/solaris/bin/java TestTitle
Unexpectedly set title to: 'null'
3,~/tmp;
---------

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