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RegistryService has two optional parameters: the mixin-names and the
      locations. The mixin-names is used for adding
    additional mixins to the exo:registry, exo:applications, exo:services,
    exo:users and exo:groups nodes of RegistryService. This allows the top level
    applications to manage these nodes in a special way. Locations is used to
    mention where exo:registry is placed for each repository. The name of each
    property is interpreted as a repository name and its value as a workspace
    name (a system workspace by default).
<component>
<type>org.exoplatform.services.jcr.ext.registry.RegistryService</type>
<init-params>
<values-param>
<name>mixin-names</name>
<value>exo:hideable</value>
</values-param>
<properties-param>
<name>locations</name>
<property name="db1" value="ws2"/>
</properties-param>
</init-params>
</component>