I noticed that recently whenever I reset Safari or clear history, my console log shows these errors:

Exception in thread "main"
java.lang.NullPointerException
Exception in thread "main" java.lang.NullPointerException
at sun.plugin2.main.sever.MozillaPlugin.getCachedSite Data(MozillaPlugin.java:499)

and these messages repeat over and over again.

Does anyone know what these errors mean and how I can fix it if it's a problem?

Thanks!