Only supports conversion from a String, but not to a String. Find below some examples of using this class in a (properly configured) Spring container using XML-based metadata:

 <bean id="errorDialog" class="...">
    <!--
        the 'messages' property is of type java.util.ResourceBundle.
        the 'DialogMessages.properties' file exists at the root of the CLASSPATH
    -->
    <property name="messages" value="DialogMessages"/>
 </bean>

 <bean id="errorDialog" class="...">
    <!--
        the 'DialogMessages.properties' file exists in the 'com/messages' package
    -->
    <property name="messages" value="com/messages/DialogMessages"/>
 </bean>

A 'properly configured' Spring container might contain a CustomEditorConfigurer definition such that the conversion can be effected transparently:

 <bean class="org.springframework.beans.factory.config.CustomEditorConfigurer">
    <property name="customEditors">
        <map>
            <entry key="java.util.ResourceBundle">
                <bean class="org.springframework.beans.propertyeditors.ResourceBundleEditor"/>
            </entry>
        </map>
    </property>
 </bean>

Please note that this PropertyEditor is not registered by default with any of the Spring infrastructure.

Thanks to David Leal Valmana for the suggestion and initial prototype.