First of all, add a bean in spring's configuration files like this:
<bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderconfigurer">
??? <property name="locations">
??????? <list>
??????????? <value>...property files</value>
??????? </list>
??? </property>
</bean>
Put the property files under classpath, then you can use ${property name} to reference properties in your property files in your spring configuration files.
Also, system properties and properties sent it by -D are also available through ${property name}.