Re: Problem with doubles

[Daniel L. Rall]

Matt, I'm very interested in integrating your changes.  Please send a patch 
and associated change log which includes information from your message below, 
but is tied to specific class and member names.

How were you thinking to make it configurable?
Matt Mower wrote:
Matt Mower wrote:
Hi folks,
I'm using the Apache XML-RPC 1.2-b1 library to communicate with a
process running on Frontier however the library seems to be improperly
encoding doubles.
According to the spec[1] only standard decimal representation is 
supported:

At this time, only decimal point notation is allowed, a plus or a
minus, followed by any number of numeric characters, followed by a
period and any number of numeric characters.

However I am occasionally seeing results being passed using scientific
notification:
<value><double>2.059538383036852E-4</double></value>

Did I report this to the right place?
I've done a little digging and the problem appears to be in:
    org.apache.xmlrpc.XmlWriter#writeObject( Object obj )
where it does:
        else if (obj instanceof Double || obj instanceof Float)
        {
            startElement("double");
            write(obj.toString());
            endElement("double");
        }
My suggested fix is to add a DecimalFormat instance to the class (it 
appears to be thread safe so could be added as a static like dateTool) 
and use:

        else if (obj instanceof Double || obj instanceof Float)
        {
            startElement("double");
            write( decimalFormat.format( obj ) );
            endElement("double");
        }
I've made this fix to my local copy and, in my limited tests, it seems 
to work fine.

There is an issue about precision since you have to specify a pattern to 
the DecimalFormat.  I rather arbitrarily used 
"0.0#######################" which was good enough for my purposes (i.e. 
I no longer get errors) but probably this is the kind of thing that 
should be configurable.

Any thoughts?