Appendix A. Compendium Services

The OSGi Service Platform Service Compendium specification defines a number of additional services that may be supported by OSGi implementations. Spring Dynamic Modules supports an additional "compendium" namespace that provides support for some of these services. By convention, the prefix osgix is used for this namespace.

<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns=""
   xsi:schemaLocation="   ">

   <!-- use the OSGi namespace elements directly -->
   <service id="simpleServiceOsgi" ref="simpleService"
       interface="" />

   <!-- qualify compendium namespace elements -->
   <osgix:property-placeholder persistent-id=""/>


At present this namespace provides support for the Configuration Admin service. Support for other compendium services may be added in future releases.

A.1.  Configuration Admin

A.1.1. Property placeholder support

Spring Dynamic Modules provides support for sourcing bean property values from the OSGi Configuration Administration service. This support is enabled via the property-placeholder element. The property placeholder element provides for replacement of delimited string values (placeholders) in bean property expressions with values sourced from the configuration administration service. The required persistent-id attribute specifies the persistent identifier to be used as the key for the configuration dictionary. The default delimiter for placeholder strings is "${...}".

Given the declarations:

<osgix:property-placeholder persistent-id=""/>

<bean id="someBean" class="AClass">
  <property name="timeout" value="${timeout}"/>

Then the timeout property of someBean will be set using the value of the timeout entry in the configuration dictionary registered under the persistent id.

The placeholder strings are evaluated at the time that the bean is instantiated. Changes to the properties made via Configuration Admin subsequent to the creation of the bean do not result in re-injection of property values. See the managed-service and managed-service-reference elements documented in appendix B if you require this level of integration. The placeholder-prefix and placeholder-suffix attributes can be used to change the delimiter strings used for placeholder values.

It is possible to specify a default set of property values to be used in the event that the configuration dictionary does not contain an entry for a given key. The defaults-ref attribute can be used to refer to a named bean of Properties or Map type. Instead of referring to an external bean, the default-properties nested element may be used to define an inline set of properties.

<osgix:property-placeholder persistent-id="">
     <property name="productCategory" value="E792"/>
     <property name="businessUnit" value="811"/> 

The persistent-id attribute must refer to the persistent-id of an OSGi ManagedService, it is a configuration error to specify a factory persistent id referring to a ManagedServiceFactory.

A.1.2. Configuration Dictionaries

Support for directly accessing configuration objects and their associated dictionaries, and for instantiating beans directly from configuration objects is on the Spring Dynamic Modules road map. See Appendix F, Roadmap for more information.