logging-log4j2

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Description

RandomAccessFileAppender does not write the header configured in the layout to the output file.

Configuration

Version: 2.22.0

Operating system: Windows 10

JDK: Temurin 11.0.16.1

Reproduction

Using the following log4j2.xml:

<Configuration>
	<Properties>
		<!-- the pattern we use for our log files -->
		<Property name="DefaultPattern">%d{DEFAULT} [%-5p] %c{1} - %m%n</Property>
		<!-- a header written of the beginning of every log file -->
		<Property name="DefaultHeader">*** HEADER ***${sys:line.separator}</Property>
	</Properties>

	<Appenders>
		<File name="file" fileName="file.log" append="false">
			<PatternLayout header="${DefaultHeader}" pattern="${DefaultPattern}" />
		</File>
		<RandomAccessFile name="randomaccessfile" fileName="randomaccessfile.log" append="false">
			<PatternLayout header="${DefaultHeader}" pattern="${DefaultPattern}" />
		</RandomAccessFile>
	</Appenders>

	<Loggers>
		<Root level="INFO">
			<AppenderRef ref="file" />
			<AppenderRef ref="randomaccessfile" />
		</Root>
	</Loggers>
</Configuration>

Combined with a simple program that just logs something, ie:

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

public class Test {
    private static final Logger LOG = LogManager.getLogger();

    public static void main(String[] args) {
        LOG.info("Test");
    }
}

This creates two files. The file.log is as expected:

*** HEADER ***
2023-11-30 16:54:04,898 [INFO ] Test - Test

But randomaccessfile.log does not contain the header line:

2023-11-30 16:54:04,898 [INFO ] Test - Test

MemoryMappedFileAppender also has the same issue.

Another issue from Jira for additional context: https://issues.apache.org/jira/browse/LOG4J2-3134 (can likely be rolled into this issue as we're migrating away from Jira over time).