How to customize PropertyPlaceholder in blueprint to perform some activity and than load some more properties?

Issue

• In spring we can customize the property placeholder by extending "PropertyPlaceholderConfigurer" class and overriding the method "processProperties" so that we can write custom code to connect to the DB and set the properties. In spring context we mention

<bean id="placeholderConfigMM" class="com.mycompany.util.PropUtil">
            <property name="locations">
                  <list>
                        <value>file:${MYCOMPANY_PROP_LOC}/configdb.properties</value>
                  </list>
            </property>
            <property name="systemPropertiesModeName" value="SYSTEM_PROPERTIES_MODE_OVERRIDE" />
      </bean>

• Similarly how we can do in camel blueprint?