slf4j-nop/src/main/java9/module-info.java

module org.slf4j.nop { 
  requires org.slf4j;
  provides org.slf4j.spi.SLF4JServiceProvider with org.slf4j.nop.NOPServiceProvider;

  exports org.slf4j.nop;
  opens org.slf4j.nop to org.slf4j;
}