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null pointer exception problem  RSS feed

 
Frances Hollis
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Posts: 17
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I am getting a null pointer exception and I don't know why. Here is the error message.

Exception in thread "main" java.lang.NullPointerException
at java.awt.Container.addImpl(Container.java:1015)
at java.awt.Container.add(Container.java:351)
at EditorFrame.<init>(NewEditor.java:23)
at NewEditor.main(NewEditor.java:9)
Press any key to continue . . .



Here is the code. I would appreciate any suggestions.

 
Freddy Wong
Ranch Hand
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Eclipse IDE Java Linux
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It's because you never initialize the outer object (JPanel).
 
marc weber
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Java Mac Safari
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Originally posted by Frances Hollis:
I am getting a null pointer exception and I don't know why. Here is the error message.

Exception in thread "main" java.lang.NullPointerException
at java.awt.Container.addImpl(Container.java:1015)
at java.awt.Container.add(Container.java:351)
at EditorFrame.<init>(NewEditor.java:23)
at NewEditor.main(NewEditor.java:9)...]

Note that the error message provides the line numbers tracing where the error occurs.

In line 9, you are calling an EditorFrame constructor. In that constructor, at line 23, you are calling contentPane.add(outer); but "outer" is still null. That is the problem with your code.
 
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