Web services are a variety of tools which can be used in a lot of means, of which the most common usage style are RPC, SOA and REST.

RPC Web services shows a scattered method call interface which is most known to developers. The most basic part of this services is the WSDL Operation.

Because the initial web services tools centered on RPC, this style is now widely spread and highly supported.

The goal of RPC in general is make distributed programming as easy as possible by creating the illusion that an exchange of data over the network that results in some processing (on another machine than the one the application is running on) is nothing more than a special kind of procedure call — one that has the special attribute of being “remote”.

The Framework
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Web services are XML-based application components that communicate using open protocols. These application components are also self-contained and self-describing. The basic Web services platform is XML and HTTP. Perhaps HTTP is more familiar since it is the mostly used internet protocol. XML on the other hands provides a language that can be utilized between different platforms and programming languages. What is cool about a web services platform is that it is quite a simple and interoperable messaging framework. It�s not perfect though, as it still has missing components such as security and routing which are now being worked on.

Originally developed by Sun Microsystems, Java is a programming language released in 1995. It is the core component of the Java platform of Sun Microsystems. Its language derives much of the syntax from C and C++ but with fewer low-level facilities and a simpler object model. Typically, it is compiled to bytecode that regardless of computer architecture, may run on any Java virtual machine (JVM).

C++ is an object oriented programming language focused on systems programming. Regarded as a middle-level language, it comprises a combination of high-level and low-level language features. It is free-form, statistically types, multi-paradigm in a usually compiled language supporting procedural programming, object-oriented programming, data abstraction and generic programming.

It was developed in 1979 by Bjarne Stroustrup at Bell Labs as an enhancement to the C programming language. It was named back then as “C with Classes”. During the year 1983, the name was changed to C++. As of the moment, a new version of the standard is in the works.

A light-weight SOAP and HTTP traffic monitor is wsmonitor (Web Services Monitor). It intercepts and logs HTTP headers and SOAP messages between a sender and receiver, displaying them in a nice format in a graphical user interface. It is lightweight, easy to use, displays XML and Fast Infoset SOAP messages, separate tabs for SOAP and HTTP traffic and Transport-level data capture.

A multithreaded, multi-user SQL database management system (DBMS) having more than 11 million installations. This program acts as a server that provides multi-user access to a number of databases.

It is one of the most popular for web applications and also acts as a database component of the BAMP,MAMP,LAMP,WAMP platforms and for tools like Bugzilla which is an open-source bug tracking. Wikipedia, a famous user online encyclopedia, uses a MySQL database.

Glassfish is an application server project by Sun Microsystems made for the Java Enterprise Edition (Java EE) platform. This free software has the name of Application Server 9.x of Sun Java System as its commercial version.

Based on a source code donated by Oracle Corporation’s TopLink persistence system and Sun, it used a derivative of Apache Tomcat as the servlet container for serving Web content. It has an added component called Gizzly which uses JAVA NIO for speed and scalability.

An extensible, high performance and easy to use web service stack is Metro. It serves as a one-top shop for your web service needs, from the simplest hello world web service to secured, reliable and transacted web service involving .NET services. It is part of the GlassFish community but it can also be used outside of it.

Looking from a functional point of view, its main features are: HTTP transport, MTOM and XOP and SOAP/TCP. Interoperable reliability, Interoperable atomic transactions, WS-Security specification and JAX-WS API.

An XML specification governing the relations between components and its allowable components of an XML document is a schema. Generating a set of Java classes that represents the schema is called “binding a schema”. A tool called a binding compiler is provided by JAXB implementations to bind a schema. It is like the way the binding compiler is invoked as it can be implementation specific.

Describing enhancements to SOAP messaging is the Web Services Security (WSS or WS-Security). It provides quality of protection through single message authentication and message integrity. These mechanisms may be used in accommodating a wide variety of encryption technologies and security models.