Chapter 3. SCA composite applications
This chapter covers
- Running a composite application in a single process
- Understanding the SCA domain
- Running a distributed composite application
- Using SCA composites as application building blocks
In this chapter we’ll look at how to use SCA and Tuscany to create and run composite applications. As the name suggests, a composite application is an application composed from other things. These other things are the basic SCA artifacts that we looked at in the previous chapter: components, implementations, services, interfaces, references, wires, properties, and bindings. To combine these into a composite application, you’ll need to understand the additional concepts of contributions, composites, domains, and execution nodes, and we’ll take a detailed look at all of these in this chapter using the travel-booking application as an example.
The code samples in this chapter are based on the simplified travel-booking application that we introduced in chapter 1. In some cases the chapter 1 code is used unchanged, and in other cases it’s extended to illustrate specific points. The code in this chapter isn’t used directly in the complete travel application. You can find the sample code for this chapter in the travel sample’s directories contributions/ introducing-tours, contributions/introducing-trips, contributions/introducing-client, and contributions/buildingblocks.