[LOG4J2-1833] NullPointerException using fileName property of RollingFile Appender with DirectWriteRolloverStrategy

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.8.1
• Fix Version/s: 2.9.0

Environment

Windows 7 64-bit JDK 8

• Assignee: Ralph Goers
• Reporter: Austin Huck
• Created: 02/Mar/17 18:47
• Updated: 23/Aug/17 19:32
• Resolved: 23/Aug/17 13:28

Description

When using a RollingFileAppender with a DirectWriteRolloverStrategy if the fileName property of the appender is set, rollover fails with a NullPointerException. If the fileName attribute is not present logging works as intended.

Configuration that produces this error:

log4j2.xml

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="warn" name="MyApp" packages="">
    <Properties>
        <Property name="baseDir">C:/logs</Property>
    </Properties>
    <Appenders>
        <RollingFile name="RollingFile" fileName="${baseDir}/app.log"
                     filePattern="${baseDir}/app-%d{yyyy-MM-dd'T'HH_mm_ss}.log">
            <PatternLayout pattern="%d %p %c{1.} [%t] %m%n" />
            <TimeBasedTriggeringPolicy interval="10"/>
            <DirectWriteRolloverStrategy>
                <Delete basePath="${baseDir}">
                    <IfFileName glob="app-*.log" />
                    <IfAccumulatedFileCount exceeds="10" />
                </Delete>
            </DirectWriteRolloverStrategy>
        </RollingFile>
    </Appenders>
    <Loggers>
        <Root level="trace">
            <AppenderRef ref="RollingFile"/>
        </Root>
    </Loggers>
</Configuration>

Stack Trace:

2017-03-02 13:38:52,023 main ERROR An exception occurred processing Appender RollingFile java.lang.NullPointerException: activeFileName
	at java.util.Objects.requireNonNull(Objects.java:228)
	at org.apache.logging.log4j.core.appender.rolling.RolloverDescriptionImpl.<init>(RolloverDescriptionImpl.java:60)
	at org.apache.logging.log4j.core.appender.rolling.DirectWriteRolloverStrategy.rollover(DirectWriteRolloverStrategy.java:194)
	at org.apache.logging.log4j.core.appender.rolling.RollingFileManager.rollover(RollingFileManager.java:362)
	at org.apache.logging.log4j.core.appender.rolling.RollingFileManager.rollover(RollingFileManager.java:278)
	at org.apache.logging.log4j.core.appender.rolling.RollingFileManager.checkRollover(RollingFileManager.java:218)
	at org.apache.logging.log4j.core.appender.RollingFileAppender.append(RollingFileAppender.java:267)
	at org.apache.logging.log4j.core.config.AppenderControl.tryCallAppender(AppenderControl.java:156)
	at org.apache.logging.log4j.core.config.AppenderControl.callAppender0(AppenderControl.java:129)
	at org.apache.logging.log4j.core.config.AppenderControl.callAppenderPreventRecursion(AppenderControl.java:120)
	at org.apache.logging.log4j.core.config.AppenderControl.callAppender(AppenderControl.java:84)
	at org.apache.logging.log4j.core.config.LoggerConfig.callAppenders(LoggerConfig.java:448)
	at org.apache.logging.log4j.core.config.LoggerConfig.processLogEvent(LoggerConfig.java:433)
	at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:417)
	at org.apache.logging.log4j.core.config.LoggerConfig.logParent(LoggerConfig.java:439)
	at org.apache.logging.log4j.core.config.LoggerConfig.processLogEvent(LoggerConfig.java:434)
	at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:417)
	at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:403)
	at org.apache.logging.log4j.core.config.AwaitCompletionReliabilityStrategy.log(AwaitCompletionReliabilityStrategy.java:63)
	at org.apache.logging.log4j.core.Logger.logMessage(Logger.java:146)
	at org.apache.logging.log4j.spi.AbstractLogger.logMessageSafely(AbstractLogger.java:2091)
	at org.apache.logging.log4j.spi.AbstractLogger.logMessage(AbstractLogger.java:1993)
	at org.apache.logging.log4j.spi.AbstractLogger.logIfEnabled(AbstractLogger.java:1852)
	at org.apache.logging.slf4j.Log4jLogger.error(Log4jLogger.java:299)