Fix an error building jd-core with its github website build instructions ?

[lmfgkfd]

When i execute the command ./gradlew build i get an error:

FAILURE: Build failed with an exception.

• What went wrong: Could not initialize class org.codehaus.groovy.reflection.ReflectionCache > Exception java.lang.NoClassDefFoundError: Could not initialize class org.codehaus.groovy.vmplugin.v7.Java7 [in thread "Daemon worker"]
• Try: Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
• Get more help at help.gradle.org

BUILD FAILED in 2s

how do i fix it ?