IntelliJ download source of a library jar error

I use gradle 6.2.2, JFrog Artifactory OSS, IntelliJ IDEA Ultimate 2020.1
I publish artifact to the Artifactory, everything works alright. I also want when developers debug the project can download the source (not decompiler), and trace into the code.

I checked JFrog Artifactory, things look OK. under 1.2.3-SNAPSHOT/ I see

maven-metadata.xml
foobar-1.2.3-SNAPSHOT-src.jar
foobar-1.2.3-SNAPSHOT.jar
foobar-1.2.3-SNAPSHOT.module
foobar-1.2.3-SNAPSHOT.pom

build.gradle snippet

task sourceJar(type: Jar) {
  classifier 'src'
  from sourceSets.main.allJava
}

publishing {
  publications {
    mavenJava(MavenPublication) {
        from components.java
        artifact tasks.sourceJar
    }
  }
}

I tried to download the source code of a class in foobar.jar in IntelliJ

IntelliJ complains:

11:46:03 PM: Executing task 'DownloadSources'...

Task :DownloadSources FAILED

1 actionable task: 1 executed

FAILURE: Build failed with an exception.

• Where:
  Initialization script 'C:\Users\xxxx\AppData\Local\Temp\1\ijmiscinit5.gradle' line: 20

• What went wrong:
  Execution failed for task ':DownloadSources'.
  Could not resolve all files for configuration ':downloadSources_4a831a47-2d8a-44e0-b835-8ff80c6fbcc8'.
  Could not find com.example:foobar:1.2.3-SNAPSHOT.
  Required by:
  project :

classifier should be sources - but you can below snippet to remove hand writing

see https://docs.gradle.org/current/userguide/publishing_maven.html#publishing_maven:complete_example

java {
    withJavadocJar()
    withSourcesJar()
}