failing to load log4j2 while running fatjar

Question

i am working on a project where i utilize log4j2 logging. while developing in intellij, all works fine and the logging is done as expected. the log4j2.xml is linked through java property passed to jvm on startup via intellij settings. but once i try to run a standalone gradle built fat-jar, i'm experiencing the following problems:

java -Dlog4j.debug=true -Dlog4j.configurationFile=/home/aaa/log4j2.xml -jar /home/aaa/myjar-SNAPSHOT.jar

exceptions:

ERROR StatusLogger Unrecognized format specifier [d]
ERROR StatusLogger Unrecognized conversion specifier [d] starting at position 16 in conversion pattern.
ERROR StatusLogger Unrecognized format specifier [thread]
ERROR StatusLogger Unrecognized conversion specifier [thread] starting at position 25 in conversion pattern.
...
ERROR StatusLogger No log4j2 configuration file found. Using default configuration: logging only errors to the console.

i don't even understand where those [thread]s come from, since i get the same error even while using a basic simplest config in my log4j2:

<?xml version="1.0" encoding="UTF-8" ?><Configuration status="WARN" monitorInterval="86400">
<Appenders>
    <Console name="console-log" target="SYSTEM_OUT">
        <PatternLayout
                pattern="%-5p %d{yyyy-MM-dd HH:mm:ss.SSS} ${hostName} %c{1} %msg %throwable{7}%n"/>
    </Console>
</Appenders>
<Loggers>
    <Root level="info" additivity="false">
        <AppenderRef ref="console-log"/>
    </Root>
</Loggers>

any thoughts are welcome. thanks.

Answer 1

in fatJar, dependencies can provide a log4j-provider.properties in the META-INF that cause this issue,

remove it in the gradle task :

task fatJar(type: Jar) {
    manifest {
        attributes 'Implementation-Title': 'project',
        'Implementation-Version': project.version,
        'Main-Class': 'com.sample.CLI'
    }
    baseName = project.name + '-all'
    from {
        configurations.compile.collect {
            it.isDirectory() ? it : zipTree(it).matching {
                exclude 'META-INF/**.RSA'
                exclude 'META-INF/MANIFEST.MF'
                exclude 'META-INF/log4j-provider.properties'
            } } }
    with jar
}