if (System.getProperty("test").equalsIgnoreCase("true"))
{
   //Do something
}

java -jar myApplication.jar -Dtest="true"

java -Dtest="true" -jar myApplication.jar

java [-options] -jar jarfile [args...]

java -Dtest="true" -jar myApplication.jar

System.getProperty("test")

java -jar -Dtest="true" myApplication.jar

"true".equalsIgnoreCase(System.getProperty("test"))

System.getProperty("test") == null || System.getProperty("test").equalsIgnoreCase("true")

java -jar myApplication.jar -Dtest=true