The idea behind CORBA is to model distributed resources as objects that provide a well-defined interface, and to invoke services through remote invocations (RPCs). Since the transfer syntax for sending messages to objects is strictly defined, it is possible to exchange requests and replies between processes running program written in arbitrary programming languages and hosted on arbitrary hardware and operating systems. Target addresses are represented as Interoperable Object References (IORs), which contain transport addresses as well as identifiers needed to dispatch incoming messages to implementations.
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O MNI B ROKER is an Object Request Broker (ORB) that is compliant to the Common Object Request Broker Architecture (CORBA) specification, revision 2.0, as defined in [1] and [2] by the Object Management Group (OMG).
Some highlights of O MNI B ROKER
are:
Full CORBA IDL support
Complete CORBA IDL–to–C++ mapping
Complete CORBA IDL–to–Java mapping
Uses IIOP as native protocol
Dynamic Invocation Interface
Dynamic Skeleton Interface
Interface Repository
Peer–to–Peer communication with nested method invocations
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Current search engines such as Google and Yahoo! are prevalent for searching the Web. Search in dynamic pages, however, is either inexistent or far from perfect. AJAX and Rich Internet Application are such applications. They are increasingly frequent on the Web (in YouTube, Amazon, GMail, Yahoo!Mail) or mobile devices and are offering a high degree of interactivity to the user, by seamlessly loading content from the server without the need to refresh the page. Current search engines cannot correctly index AJAX applications. This produces false positives and false negatives, because search engines do not understand the application logic that loads content dynamically. Crawling an AJAX application is a difficult problem. Since the user invokes events on the page, crawling must identify the different application states generated by the client-side logic.
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Exactly how jEdit is started depends on the operating system. For example, on Unix you can run “jedit” at the command line, or select jEdit from a menu; on Windows, you can double-click on the jEdit icon or select it from the Start menu.

If jEdit is started while another copy is already running, control is transferred to the running copy, and a second instance is not loaded. This saves time and memory if jEdit is started multiple times. Communication between instances of jEdit is implemented using TCP/IP sockets; the initial instance is known as the server, and subsequent invocations are clients.
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This document describes the rationale behind the Web Service Integration Gateway (WSIG) and how to install, configure and use it. The WSIG (version 0.4) is a JADE add-on that provides support for bidirectional invocation of Web services from JADE agents, and JADE agent services from Web service clients. This is the first public release of this add-on and as such it should be treated as a beta that is subject to change at any time.
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Verification of programs presented in widely-used object-oriented programming languages, such as C++, C#, Java, is a subject of much current interest. The well-known approach to program verification is based on Hoare-like axiomatic semantics. Difficulties of developing compact and transparent axiomatic semantics of object-oriented programming languages are connected with such constructs as overloading, dynamic binding of methods, exception handling, static initialization of classes. Axiomatic semantics has been proposed for different sequential subsets of Java in [3, 4, 7–10]. While compact and transparent axiomatic semantics has been developed for separate difficult Java constructs, it turned out to be cumbersome and inconvenient for the practical use in the case of a wide sequential Java subset.
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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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This programmer’s guide is complemented by the administrator’s guide and the HTML documentation available in the directory jade/doc. If and where conflict arises between what is reported in the HTML documentation and this guide, preference should be given to the HTML documentation that is updated more frequently. JADE (Java Agent Development Framework) is a software development framework aimed at developing multi-agent systems and applications conforming to FIPA standards for intelligent agents. It includes two main products: a FIPA-compliant agent platform and a package to develop Java agents. JADE has been fully coded in Java and an agent programmer, in order to exploit the framework, should code his/her agents in Java, following the implementation guidelines described in this programmer’s guide.
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