Java Reference
In-Depth Information
One thing noticeably absent from XML-RPC is a way to represent data as an object. The
protocol wasn't designed with object-oriented programming in mind, but you can repre-
sent reasonably complex objects with the
array
and
struct
types.
By design, XML-RPC is a simple remote procedure call protocol that is well suited to
programming across a network. The protocol has become one of the key elements of web
services implemented by many developers of software on Windows, Macintosh, Linux,
and UNIX systems.
The full XML-RPC specification is available on XML-RPC.Com at
NOTE
More than 75 implementations of XML-RPC are available today for a variety of lan-
guages and platforms.
After the release of XML-RPC, the specification was extended to create another RPC
protocol called SOAP, the Simple Object Access Protocol.
SOAP shares some of the design goals of XML-RPC but has been expanded to better
support objects, user-defined data types, and other advanced features, resulting in a sig-
nificantly more complex protocol. SOAP has also become widely popular for web ser-
vices and other decentralized network programming.
Because SOAP is an extension of XML-RPC, it raises the question
of why the latter protocol is still in use.
When SOAP came out and was considerably more complex than
XML-RPC, there was enough difference between the related proto-
cols that an argument could be made for using either one,
depending on the needs of a particular project.
To find out more about SOAP and public servers that can be used
with SOAP clients, visit the website
http://www.xmethods.com.
NOTE
20
XML-RPC is a protocol transmitted via HTTP, the standard for data exchange between
web servers and web browsers. The information that it transmits is not web content.
Instead, it is XML data encoded in a specific way.
