What does java -Dnop do?

Question

I was looking at the complete command line of my java process running in a tomcat container and was surprised to see a -Dnop in there? Does anyone know what does it do and which component must have put it in there? I have not configured anything like that in my catalina.sh. I do set other system properties like Xms and Xmx, PermGen size, timezone, etc.

sps -wp 20301

/usr/local/java/jdk1.6.0.24/bin/amd64/java -Dnop -Xms128m -Xmx2048m -XX:PermSize=128m -Dcom.sun.management.jmxremote.port=8919 -Dcom.sun.management.jmxremote.authenticate=false -Dcom.sun.management.jmxremote.ssl=false -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Duser.timezone=GMT -Djava.endorsed.dirs=/prod/tomcat/endorsed -classpath /prod/tomcat/bin/bootstrap.jar -Dcatalina.base=/prod/tomcat -Dcatalina.home=/prod/tomcat -Djava.io.tmpdir=/prod/tomcat/temp org.apache.catalina.startup.Bootstrap start

Answer 1

It sets the system property nop. I find it mentioned in these notes.

https://github.com/grgrzybek/tomcat-slf4j-logback

edit this bugzilla entries implies it is literally "no-op", i.e. a setting to fulfil the wrapper script requirements it can be any value, e.g. -DKilokahn would be valid too.

Set LOGGING_CONFIG to a harmless flag if JULI is not used. With my Sun JVM, a plain -D is safe. I don't know how portable this is. It isn't very pretty.

https://issues.apache.org/bugzilla/show_bug.cgi?id=45585