spring boot 2.2: newest classgraph is not loaded

when the spring boot container is started, the following error occurs:

***************************
APPLICATION FAILED TO START
***************************

Description:

An attempt was made to call a method that does not exist. The attempt was made from the following location:

    org.webjars.WebJarAssetLocator.findWebJars(WebJarAssetLocator.java:122)

The following method did not exist:

    io.github.classgraph.Resource.getClasspathElementURI()Ljava/net/URI;

The method's class, io.github.classgraph.Resource, is available from the following locations:

    jar:file:/C:/Users/X048833/.m2/repository/io/github/classgraph/classgraph/4.6.32/classgraph-4.6.32.jar!/io/github/classgraph/Resource.class

It was loaded from the following location:

    file:/C:/Users/X048833/.m2/repository/io/github/classgraph/classgraph/4.6.32/classgraph-4.6.32.jar


Action:

Correct the classpath of your application so that it contains a single, compatible version of io.github.classgraph.Resource

the mvn dependency:tree -Dverbose command shows that the newest version 4.8.44 is omitted, instead the version 4.6.32 is used.

[INFO] +- org.springdoc:springdoc-openapi-ui:jar:1.1.49:compile
[INFO] |  +- (org.springdoc:springdoc-openapi-core:jar:1.1.49:compile - omitted for duplicate)
[INFO] |  +- org.webjars:swagger-ui:jar:3.24.0:compile
[INFO] |  \- org.webjars:webjars-locator:jar:0.37:compile
[INFO] |     +- org.webjars:webjars-locator-core:jar:0.41:compile (version managed from 0.39)
[INFO] |     |  +- (org.slf4j:slf4j-api:jar:1.7.28:compile - version managed from 1.7.7; omitted for duplicate)
[INFO] |     |  +- (io.github.classgraph:classgraph:jar:4.8.44:compile - omitted for conflict with 4.6.32)

 +- org.springdoc:springdoc-openapi-core:jar:1.1.49:compile
[INFO] |  +- org.springdoc:springdoc-openapi-common:jar:1.1.49:compile
[INFO] |  |  +- (org.springframework.boot:spring-boot-autoconfigure:jar:2.2.0.RELEASE:compile - version managed from 2.0.9.RELEASE; omitted for duplicate)
[INFO] |  |  +- (org.springframework:spring-web:jar:5.2.0.RELEASE:compile - version managed from 5.0.13.RELEASE; omitted for duplicate)
[INFO] |  |  +- io.swagger.core.v3:swagger-models:jar:2.0.10:compile
[INFO] |  |  |  \- (com.fasterxml.jackson.core:jackson-annotations:jar:2.10.0:compile - version managed from 2.9.10; omitted for duplicate)
[INFO] |  |  +- io.swagger.core.v3:swagger-annotations:jar:2.0.10:compile
[INFO] |  |  +- io.swagger.core.v3:swagger-integration:jar:2.0.10:compile
[INFO] |  |  |  +- io.github.classgraph:classgraph:jar:4.6.32:compile

Thanks for fixing this.

[tomasj]

It looks like springdoc-openapi-ui depends on springdoc-openapi-core to include correct version of io.github.classgraph. But in version 1.1.49 an accident happened and springdoc-openapi-ui for some reason assumes newer version of that dependency, which is not there.

I’m sure guys will update it in next release. For now it can be fixed by simply excluding and forcing the dependency like this:

<dependency>
	<groupId>org.springdoc</groupId>
	<artifactId>springdoc-openapi-core</artifactId>
	<version>1.1.49</version>
	<exclusions>
		<exclusion>
			<groupId>io.github.classgraph</groupId>
			<artifactId>classgraph</artifactId>
		</exclusion>
	</exclusions>
</dependency>
<dependency>
	<groupId>org.springdoc</groupId>
	<artifactId>springdoc-openapi-ui</artifactId>
	<version>1.1.49</version>
</dependency>
<dependency>
	<groupId>io.github.classgraph</groupId>
	<artifactId>classgraph</artifactId>
	<version>4.8.44</version>
</dependency>

[bnasslahsen]

@Simbosan,

springdoc-openapi-webflux-core is included by transitivity when you declare springdoc-openapi-webflux-ui. Please note, that declaring the following is enough for a project :

 <dependency>
        <groupId>org.springdoc</groupId>
        <artifactId>springdoc-openapi-webflux-ui</artifactId>
        <version>1.2.31</version>
    </dependency>

If you are facing any dependencies problem, you can add the link to a simple demo project to reproduce it.