How the XML parser handles errors

When the XML parser detects an error in an XML document, it generates an XML exception event and passes control to your processing procedure.

The parser passes the following information in special registers to the processing procedure:

• XML-EVENT contains 'EXCEPTION'.
• XML-CODE contains a numeric exception code.

  The exception codes are described in the related references about XML PARSE exceptions.

• For fatal exceptions, XML-TEXT or XML-NTEXT contains the document text up to and including the point where the exception was detected.
• For the warning exceptions issued for using an undeclared prefix, XML-TEXT or XML-NTEXT contains the fully qualified attribute name or element name. That is, the name includes the undeclared prefix and the separator colon (:).
• If XMLPARSE(COMPAT) is in effect, XML-TEXT or XML-NTEXT contains the document text up to and including the point where the exception was detected.
• If XMLPARSE(XMLSS) is in effect, XML-TEXT or XML-NTEXT contains the document text up to the point where the error or anomaly was detected. If you process the XML document one segment at a time, the applicable special register contains only the current segment.

All other XML special registers are empty with length zero.

For XMLPARSE(XMLSS):

Parsing cannot continue after a fatal exception even if you set XML-CODE to zero in the processing procedure. Upon return to the parser from the processing procedure, the parser transfers control to the ON EXCEPTION phrase, if specified; otherwise the parser transfers control to the end of the XML PARSE statement. XML-CODE contains the original exception code set by the parser.

For XMLPARSE(COMPAT):

The processing procedure might be able to handle an exception so that parsing continues if the exception code is within one of the following ranges:

• 1 - 99
• 100,001 - 165,535

If the exception code has any other nonzero value, parsing cannot continue.

Encoding conflicts: The exceptions for encoding conflicts (50 - 99 and 300 - 399) are signaled before the parsing of the document begins. For these exceptions, XML-TEXT or XML-NTEXT is either length zero or contains only the encoding declaration value from the document.

Exception codes 1 - 49: An exception for which the exception code is in the range 1 - 49 is a fatal error according to the XML specification. Therefore, the parser does not continue normal parsing even if the processing procedure handles the exception. However, the parser does continue scanning for further errors until it reaches the end of the document, or until the existing XML EVENT token array is exhausted. For these exceptions, the parser does not signal any further normal events except the END-OF-DOCUMENT event.