Web Services Description Language (WDSL), originally developed by IBM, Microsoft, and others, is an XML format for technical description of Web services. In this tutorial, Mike Olson and Uche Ogbuji introduce WSDL4Py, an open-source Python library for WSDL 1.1 hosted by IBM developerWork’s open-source zone. Usage of the library is explained, as well as discussion of its development.
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XML Web Services provide a flexible API for building distributed systems as a collection of endpoints that can send and receive SOAP messages. These systems are secured using message-based cryptographic mechanisms defined in a series of specifications developed by Microsoft, IBM, and others. Such home-grown security protocols often go wrong; they are prone to a well-known class of attacks, formalized by Dolev and Yao, where an attacker can intercept, modify, and replay messages. The vulnerability is only increased by the flexible message formats and complex trust configurations allowed by the standards. Our goal is to verify the security of families of protocol configurations, such as those deployed for Microsoft’s WSE and Indigo web services implementations.
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Many developers have learned to use PHP over the years because it’s a good solution for creat- ing Web pages and the price is right. The PHP acronym is like many other new acronyms for the Internet—the acronym is recursive (refers back to itself). PHP stands for PHP Hypertext Processor. This general-purpose HTML scripting language works much like ASP (see Chapter 6) or other page description languages you might have used. Essentially, you mix HTML with scripting information. When the PHP process sees HTML, it sends the text directly to the user. It processes any scripting information, and passes the resulting HTML to the user as well.
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Many developers have learned to use PHP over the years because it’s a good solution for creating Web pages and the price is right. The PHP acronym is like many other new acronyms for the Internet—the acronym is recursive (refers back to itself). PHP stands for PHP Hypertext Processor. This general-purpose HTML scripting language works much like ASP (see Chapter 6) or other page description languages you might have used. Essentially, you mix HTML with scripting information. When the PHP process sees HTML, it sends the text directly to the user. It processes any scripting information, and passes the resulting HTML to the user as well.
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Concurrent programming is still challenging and difficult. “Since concurrency techniques have become indispensable for programmers who create highly available services and reactive applications, temporal dimensions of correctness introduced by concurrency, i.e., safety and liveness, are central concerns in any concurrent design and its implementation” [Lea 98]. And without expert guidance and concurrent design-pattern description, they’re expected to occasionally fail. Thus providing significant examples and paradigms for teaching good and correct style is of prime importance.

Learning concurrency paradigms is necessary but it is not sufficient. The choice of the run-time semantics must be known since it may introduce subtle design and programming errors. It is the aim of this paper to exemplify the importance of process queuing and awaking policies (whether processes are named threads or tasks) resulting from possible choices of the monitor concept implementation.
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Apply XDoclet to a J2EE project What is XDoclet? • Javadoc metadata templating engine • Attribute-oriented programming • Outgrown its EJBDoclet roots Why XDoclet? • Avoid code metadata duplication • Pragmatic Programming: • DRY - Don’t Repeat Yourself • Program close to the problem domain • Write code that writes code • JSR’s 175 & 181 JSR 175 A metadata facility for the Java Programming Language would allow classes, interfaces, ?elds, and methods to be marked as having particular attributes. JSR 181
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In both e-business and e-science, we often need to integrate services across distributed, heterogeneous, dynamic “virtual organizations” formed from the disparate resources within a single enterprise and/or from external resource sharing and service provider relationships. This integration can be technically challenging because of the need to achieve various qualities of service when running on top of different native platforms. We present an Open Grid Services Architecture that addresses these challenges.
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