In this chapter, we have introduced some of the basic web services concepts so that you could get acquainted with these technologies before using them to enhance your Ticket application.

Then, we went through SOAP-based web services that are based on a contract between the service and the client defined by the WSDL file. SOAP web services are an excellent option for integrating systems when you have well-defined, abstract operations exposed using standard XML files.

Then we discussed REST services. The key to the REST methodology is to write web services using an interface that is already well known and widely used: the URI. The twist here is to identify the key system resources (this can be entities, collections, or anything else the designer thinks is worthy of having its own URI) and expose them using standard methods that are mapped to standard methods. In this case, the HTTP verbs are mapped to resource-specific semantics.

We have discussed a lot about application server resources. In the next chapter, we will see how to manage them using the Command Line Interface and JBoss client libraries.