Why do I get a Null Pointer Exception?

Posted by Roman on Stack Overflow See other posts from Stack Overflow or by Roman
Published on 2010-04-21T13:04:48Z Indexed on 2010/04/21 13:13 UTC
Read the original article Hit count: 127

Filed under:

java

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nullpointerexception

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windowlistener

I have this code:

    Manager manager = new Manager("Name");
    MyWindowListener windowListener = new MyWindowListener(); 
    manager.addWindowListener(windowListener);

Eclipse writes that I have a NullPointerException in the last line. What can be the reason for that. I do have constructors in the Manager and MyWindowListener.

If it's important MyWindowListener implements WindowListener.

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