<configuration debug="true">
    <springProperty name="logbackFilePath"
        source="clamp.config.logback.path" />
    <springProperty name="logbackFileName"
        source="clamp.config.logback.filename" />
    <springProperty name="logDirectory"
        source="clamp.config.log.path" />
        
    <if condition='isNull("logbackFilePath")'>
        <then>
            <!-- Classpath case -->
            <include resource="${logbackFileName}" />
        </then>
        <else>
            <!-- File system case -->
            <include file="${logbackFilePath}/${logbackFileName}" />
        </else>
    </if>
</configuration>