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SAX problem

 
John Coleman
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I get
java.lang.NullPointerException
at org.apache.xerces.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1132)
at com.abnamro.wcs.orchard.gui.madj.ImportXMLFile.main(ImportXMLFile.java:179)
Exception in thread "main"
from the code below. I copied the source from the JAXP example so I cannot understand why it does not work. What is missing?
Any help much appreciated. Please reply to address below.

reply to:
[EMAIL]john.s.coleman@uk.abnamro.com [/EMAIL]
[ April 29, 2002: Message edited by: Jim Yingst ]
 
John Wetherbie
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I'm having difficulty locating line 179 where the exception is thrown. COuld you mark it someway?
It sounds like something is not being created properly but what the reason is is hard to say.
John
 
Jim Yingst
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Ugh. That was too much work just to get the code looking semi-presentable. Anyway, the exception must have been thrown by the line
xmlReader.parse(convertToFileURL(aFileName));
as that's the only place parse() is called. But it's not really clear what the cause is.
 
John Coleman
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Jim,
You are correct that the error occurs in the .parse method, and also that there is no way of diagnosing the error.
This makes me wonder if the Sax example in JAXP works. I also wonder if anyone unserstands Sax enough to tell me what is missing? Should I contact the author?
John
 
John Coleman
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The problem is solved. Although the error message appears to point to a problem in the .parse method, in reality it is the methods that I override that cause the error. In this case a stepwise debug reveals that a string variable was not initialised before use in .startElement method.
The moral of the tale is not to let cryptic error messages put you off running a debug or looking for obvious mistakes.
thanks anyway,
John
 
With a little knowledge, a cast iron skillet is non-stick and lasts a lifetime.
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