Identifying parse errors in XPCML

When validating XPCML schema documents, a fully validating XML parser may generate warnings, non-fatal parse errors, and fatal parse errors.

Warnings and non-fatal parse errors do not cause the parse to fail. You might want to examine warnings and non-fatal errors to help you determine problems with your XPCML source. Fatal parse errors cause the parse to terminate with an exception.

To display warnings and non-fatal parser errors when parsing an XPCML document, turn tracing on in your application and set the trace category to PCML.

Example

A fully validating XML parser generates an error for any numeric parameter type that does not have a value. The following example shows sample XPCML source and the resulting non-fatal parse error:

XPCML source

     <program name="prog1"/>
        <parameterList>
           <intParm name="parm1"/>
        </parameterList>
     </program>

Resulting error

     Tue Mar 25 15:21:44 CST 2003  [Error]: cvc-complex-type.2.2: Element
     'intParm' must have no element [children], and the value must be valid.

To prevent logging this kind of error, add the nil=true attribute to the intParm element. The nil=true atttribute signals to the parser that you have deliberately left the element empty.. Here is the previous XPCML source with the nil=true atttribute added:

     <program name="prog1"/>
        <parameterList>
           <intParm xsi:nil="true" name="parm1"/>
        </parameterList>
     </program>