Web services, Java style

Early access version of Sun's Web Services Developer Pack offers a sneak peek at emerging technologies

See correction below

Now that Web services have firmly established themselves in the enterprise, developers face mounting pressure to keep up with the latest development and deployment technologies -- sometimes even before they have been released. Thankfully, most of the big names in Web services are only too happy to help, which explains the arrival of Sun Microsystems' Java Web Services Developer Pack (WSDP), Early Access Release 1.

WSDP offers a useful set of APIs (application programming interfaces), deployment tools, and testing applications that can help straighten the Web-services learning curve. Like IBM's Web Services Toolkit, WSDP is not ready for production use (except possibly among the most bleeding-edge enterprises). But the embedded technologies are certain to wind up in any number of development tools (such as Borland's JBuilder) and middle-tier application servers (such as those offered by BEA), so developers who examine WSDP now will find themselves a step ahead of the competition.

At the core of WSDP is a set of Java APIs. Together, the APIs let Java-based enterprises deploy Web services that can support SOAP (Simple Object Access Protocol), WSDL (Web Services Description Language), and UDDI (Universal Description, Discovery, and Integration), along with basic XML manipulation.

You get a JAXP (Java API for XML Processing), which supports the creation, receipt, and manipulation of XML data, including XML Schema; a JAX-RPC (Java API for XML-based Remote Procedure Calls) that enables the creation of Web services using SOAP and WSDL; a JAXM (Java API for XML Messaging) to support XML messaging via SOAP-capable messaging profiles; and a JAXR (Java API for XML Registries) that supports access to UDDI registries.

All of the APIs in WSDP are also in Sun's Java XML Pack. These APIs are updated quarterly, letting developers keep up with changes in emerging Web services.

Sun also includes a handy JSP (Java Server Page) library of frequently-used functions for processes like XSLT (Extensible Style Language Transformation) and using JavaBeans in JSPs. These shortcuts can slash development time because after they are created they can be reused by multiple designers and developers. Developers can also use the built-in UDDI registry server during local development to validate registry access.

Furthermore, like IBM's Toolkit, Sun's WSDP boasts the Jakarta Tomcat 4 Java Servlet and JSP container, which means developers testing Web services based on Servlet or JSP technologies can validate execution activity. The Ant open-source build management tool is also included.

Enterprises concerned with Web services security will want to examine the package's JSSE (Java Secure Socket Extension) API, which supports data encryption, authentication on the server side (and optionally on the client side), and message integrity. The API supports SSL (Secure Sockets Layer) and Transport Layer Security across any TCP/IP connection. Since JSSE will be included in the soon-to-be released Java 1.4 platform, developers who catch on now can get a head start on their peers.

In-depth learning

One of WSDP's strongest features is its detailed documentation and tutorial, which offer more than 500 pages of learning aids. Thanks in large part to those materials, we were able to seamlessly install, access, and work with the solution on several platforms, including Red Hat Linux 7.2, Solaris 8 and 9, and Windows 2000.

Like IBM's Toolkit, WSDP lacks graphical development tools (although it does boast a graphical installer). Developers who do not already use IDEs (Integrated Drive Electronics) will find the going very easy, especially considering the Ant-build management tool, which lets developers perform conditional compilations or customized processing during compilation.

And developers who do use IDEs will ultimately find that understanding and learning Web services technologies is much easier without the overhead of an IDE.

Sun's WSDP is only a reference implementation, not a development platform. But it gives developers a leg up on several emerging Web services technologies. A second release is expected in early spring, and the production version is slated for early summer. Best of all, the package is free, so enterprise strategists planning to implement a Java-based approach to Web services have nothing to lose by adopting it now.

Correction

In this article, IDE should stand for "integrated development environment."

Copyright © 2002 IDG Communications, Inc.