A service component is defined in the configuration.xml file by using <component> element.
There is only one required information when defining a service - the service implementation class, specified using <type>
Every component has a <key> that identifies it. If not explicitly set, a key defaults to the value of <type>. If the key is loaded as a class, the Class or String object will be used as a key.
The usual approach is to specify an interface as a key.
Example 7.1. Example of service component configuration:
<?xml version="1.0" encoding="ISO-8859-1"?>
<configuration
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.exoplaform.org/xml/ns/kernel_1_0.xsd
http://www.exoplaform.org/xml/ns/kernel_1_0.xsd"
xmlns="http://www.exoplaform.org/xml/ns/kernel_1_0.xsd">
<component>
<key>org.exoplatform.services.database.HibernateService</key>
<type>org.exoplatform.services.database.impl.HibernateServiceImpl</type>
...
</component>
</configuration>