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Use the same classpath ordering for an exploded jar and an archive

demo.zip

Print classloader urls in main method:

	public static void main(String[] args) {
		URLClassLoader classLoader = (URLClassLoader) Thread.currentThread().getContextClassLoader();
		for(URL url : classLoader.getURLs()) {
			System.err.println(url);
		}
		SpringApplication.run(DemoApplication.class, args);
	}
  • Run as jar
mvn clean package -DskipTests
$ java -jar target/demo-0.0.1-SNAPSHOT.jar

output:

jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/classes!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/spring-boot-starter-1.5.3.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/spring-boot-1.5.3.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/spring-context-4.3.8.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/spring-aop-4.3.8.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/spring-beans-4.3.8.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/spring-expression-4.3.8.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/spring-boot-autoconfigure-1.5.3.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/spring-boot-starter-logging-1.5.3.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/logback-classic-1.1.11.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/logback-core-1.1.11.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/jcl-over-slf4j-1.7.25.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/jul-to-slf4j-1.7.25.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/log4j-over-slf4j-1.7.25.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/spring-core-4.3.8.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/snakeyaml-1.17.jar!/
jar:file:/private/tmp/demo/target/demo-0.0.1-SNAPSHOT.jar!/BOOT-INF/lib/slf4j-api-1.7.25.jar!/
  • Run in directory
cd target
unzip demo-0.0.1-SNAPSHOT.jar -d demo
cd demo
java org.springframework.boot.loader.PropertiesLauncher

output:

file:/private/tmp/demo/target/demo/BOOT-INF/classes/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/jcl-over-slf4j-1.7.25.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/jul-to-slf4j-1.7.25.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/log4j-over-slf4j-1.7.25.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/logback-classic-1.1.11.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/logback-core-1.1.11.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/slf4j-api-1.7.25.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/snakeyaml-1.17.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/spring-aop-4.3.8.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/spring-beans-4.3.8.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/spring-boot-1.5.3.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/spring-boot-autoconfigure-1.5.3.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/spring-boot-starter-1.5.3.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/spring-boot-starter-logging-1.5.3.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/spring-context-4.3.8.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/spring-core-4.3.8.RELEASE.jar!/
jar:file:/private/tmp/demo/target/demo/BOOT-INF/lib/spring-expression-4.3.8.RELEASE.jar!/

The order of classLoader urls is very important.

When run app in exploded directory, the order of jars is different.

I recommend add a index file BOOT-INF/INDEX.LIST to save the order of jars.

See also: