🚀 go-pugleaf

Alan Shiers wrote:

> I'm working on a project where I'm trying to save to file all the objects
> contained in a class that extends JPanel and implements Serializable.  When
> I attempt the save using the following code:

Have you stepped through that code in the debugger?
Where does it go off the tracks?

You are trying to serialize an object which
may not exist: is "docPanel" null?

> FileOutputStream fStream = null;
> ObjectOutputStream stream = null;
> [...]
> catch(Exception ex)
> {
>     ex.printStackTrace();
>     try{stream.close();fStream.close();}

In general, check variable for whether they
are not null before invoking methods on them:

     try {
      if ( stream != null )
        stream.close();
      ....

This motif is very commonly used in books
and demos.

A minor point, but you are closing the streams
in two places.

Finally, it's more proper to close them in a
*finally* block.  Again, this is an oft-recurring
motif of a type that should be picked up by
extensive reading of books and demo code.


-- 


Paul Furbacher (TeamB)

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