gradlew clean build failed

[RaymondLam1]

When I download code and gradlew clean build, I got error blow:

A problem occurred configuring root project 'net-http'.
> Could not resolve all files for configuration ':classpath'.
   > Could not find org.xbib.gradle.plugin:gradle-plugin-shadow:1.1.1.
     Searched in the following locations:
       - https://xbib.org/repository/org/xbib/gradle/plugin/gradle-plugin-shadow/1.1.1/gradle-plugin-shadow-1.1.1.pom
       - https://plugins.gradle.org/m2/org/xbib/gradle/plugin/gradle-plugin-shadow/1.1.1/gradle-plugin-shadow-1.1.1.pom
     Required by:
         project :

How can I fix it, thanks.