Re: Off-spec XML-RPC

[josh lucas]

Rogers -

Sorry for the delay in responding. I'm not sure how one could handle a non-conforming response, I'll have to look at that.

I'd also drop a note to the folks working on the Advogato code..

http://www.advogato.net/proj/mod_virgule/

http://zork.net/mailman/listinfo/virgule-dev


josh


On Thursday, October 24, 2002, at 10:58 AM, Rogers Cadenhead wrote:

I'm writing a Java application that uses Apache XML-RPC to call
methods on Advogato's XML-RPC interface. Advogato's diary.getDates()
method bombs out with a NullPointerException every time it is run.

After bouncing around your source code for a while (nice work!), I
found that the cause appears to be some off-spec XML-RPC in
Advogato's response:

<?xml version="1.0"?>
<methodResponse>
  <params>
    <param>
      <array>
        <data>
          <value>
            <dateTime.iso8601>20020707T11:25:37</dateTime.iso8601>
          </value>
          <value>
            <dateTime.iso8601>20020707T11:37:12</dateTime.iso8601>
          </value>
        </data>
      </array>
    </param>
  </params>
</methodResponse>

As you can see, the array element is not enclosed within a value
element. This causes the startElement() method of XmlRpc to throw a
NullPointerException here:

else if ("array".equals (name))
{
    currentValue.setType (ARRAY);
}

currentValue is null at this point because startElement() does not
set up the currentValue object until it encounters a value element,
and Advogato's response doesn't contain one outside of the array
element.

I don't know how (or if) you want to deal with off-spec XML-RPC.
However, since this NullPointerException provides so little user
feedback on the cause of the problem, I thought it might be worth
mentioning here.
--
Rogers Cadenhead, [EMAIL PROTECTED] on 10/24/2002
Weblog: http://www.pycs.net/workbench