- **Logging Abstraction** (`org.codelibs.core.log`) - Flexible logging system supporting JCL (Jakarta Commons Logging) and JUL (Java Util Logging)
- **Concurrent Utilities** (`org.codelibs.core.concurrent`) - Thread-safe collections and concurrency helpers using modern concurrent APIs

jvm.crawler.options=\
-Djava.awt.headless=true\n\
-Dfile.encoding=UTF-8\n\
-Djna.nosys=true\n\
-Djdk.io.permissionsUseCanonicalPath=true\n\
-Dhttp.maxConnections=20\n\
-Djava.util.logging.manager=org.apache.logging.log4j.jul.LogManager\n\
-server\n\
-Xms128m\n\
-Xmx512m\n\
-XX:MaxMetaspaceSize=128m\n\
-XX:CompressedClassSpaceSize=32m\n\
-XX:-UseGCOverheadLimit\n\
-XX:+UseTLAB\n\
-XX:+DisableExplicitGC\n\

     * -Dfile.encoding=UTF-8<br>
     * -Djna.nosys=true<br>
     * -Djdk.io.permissionsUseCanonicalPath=true<br>
     * -Dhttp.maxConnections=20<br>
     * -Djava.util.logging.manager=org.apache.logging.log4j.jul.LogManager<br>
     * -server<br>
     * -Xms128m<br>
     * -Xmx512m<br>
     * -XX:MaxMetaspaceSize=128m<br>
     * -XX:CompressedClassSpaceSize=32m<br>
     * -XX:-UseGCOverheadLimit<br>
     * -XX:+UseTLAB<br>

			<artifactId>log4j-slf4j-impl</artifactId>
			<version>${log4j.version}</version>
		</dependency>
		<dependency>
			<groupId>org.apache.logging.log4j</groupId>
			<artifactId>log4j-jul</artifactId>
			<version>${log4j.version}</version>
		</dependency>
		<dependency>
			<groupId>co.elastic.logging</groupId>
			<artifactId>log4j2-ecs-layout</artifactId>