톰캣에서 Spring & Log4j 리스너 사용 시 발생가능한 문제

톰캣에서 Spring & Log4j 리스너 사용 시 발생가능한 문제

예외 메시지 1 : Error reading tld listeners java.lang.NullPointerException
예외 메시지 2 : ApplicationContext.java:647 : Shutting down log4j

문제는 org.springframework.web.util.Log4jConfigListener가 org.springframework.web.context.ContextLoaderListener 전에 로드되어야 한다는 점이다.

샘플 web.xml

<!-- [Log4j configuration file path] =========================================== -->
    <context-param>
        <param-name>log4jConfigLocation</param-name>
        <param-value>/WEB-INF/conf/log4j.xml</param-value>
    </context-param>
    <context-param>
        <param-name>webAppRootKey</param-name>
        <param-value>webapp.root</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
    </listener>
    
    <!-- [PropertySet configuration file path] ===================================== -->
    <context-param>
        <param-name>propertyConfigLocation</param-name>
        <param-value>/WEB-INF/conf/property-set.xml</param-value>
    </context-param>
    <listener>
        <listener-class>com.srpost.salmon.spi.propertyset.PropertySetConfigListener</listener-class>
    </listener>
    
    <!-- [Spring configuration file path] ========================================== -->
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/conf/application-*.xml</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
    
    <!-- [Jakarta common-upload temp file cleaner] ================================= -->
    <listener>
       <listener-class>org.apache.commons.fileupload.servlet.FileCleanerCleanup</listener-class>
    </listener>