Today, companies rely on thousands of different software applications each with their own role to play in running a business. To name just a few, database applications store information about customers and inventories, web applications allow customers to browse and purchase products online, and sales tracking applications help business identify trends and make decisions for the future.
These different software applications run on a wide range of different platforms and operating systems, and they are implemented in different programming languages. As a result, it is very difficult for different applications to communicate with one another and share their resources in a coordinated way.
Take, for example, a company that has its customer data stored in one application, its inventory data stored in another application, and its purchasing orders from customers in a third. Until now, if this company wanted to integrate these different systems, it had to employ developers to create custom bridging software to allow the different applications to communicate with one another. However, these sorts of solutions are often piecemeal and time consuming. As soon as a change is made to one application, corresponding changes have to be made to the applications linked to it and to the bridges that link the applications together.
Another solution would be for a human being to bridge the communication gap between two applications, an inefficient and error-prone approach.
To solve the problem of application-to-application communication, businesses need a standardized way for applications to communicate with one another over networks, no matter how those applications were originally implemented. Web services provide exactly this solution by providing a standardized method of communication between software applications. With a standardized method of communication in place, different applications can be integrated together in ways not possible before. Different applications can be made to call on each other's resources easily and reliably, and the different resources that applications already provide can be linked together to provide new sorts of resources and functionality.
Moreover, application integration becomes much more flexible because web services provide a form of communication that is not tied to any particular platform or programming language. The interior implementation of one application can change without changing the communication channels between it and the other applications with which it is coordinated. In short, web services provide a standard way to expose an application's resources to the outside world so that any user can draw on the resources of the application.
In this tutorial you will learn the basic concepts behind building web services with WebLogic Workshop. You will create a web service that receives a name a returns a greeting. Specifically, you will learn how to build a synchronous method that will receive the name and return the greeting, and how to build an asynchronous, buffered method that will receive the name and invoke a buffered callback method to return a greeting.