## The structure of a Service Component

A service component is implemented by a class. To identify it as a service component, it contains an @service annotation. The SCA runtime will use the file name of the script to determine the component name, by convention. The class and script file must therefore share the same name.

PHP SCA components always expose a service, and there is no way for a component to be invoked other than to be called as a result of a Web service request, or called directly from another component or from a script. For this reason a valid PHP SCA component will always contain an @service annotation and at least one public method.

Each SCA Component requires that the SCA.php script is included. As well as containing the definition of the SCA class, this script contains executable PHP code that will run whenever the script is called, and which will be responsible for making the component behave as needed.

Caution

It is very important that if your file contains other includes, they come before the include for SCA.php. If there are includes after the include for SCA.php, they will not have been processed when the SCA runtime runs your class.

The example below illustrates this overall structure

Example #1 The structure of an SCA for PHP component

`<?php
// any includes
include "SCA/SCA.php";
/**
* @service
*/
class ConvertedStockQuote {
// instance variables, business logic, including at least one public method
}
?>`