This class should *definitely* be immutable. Then all synchronization can be removed. The memory footprint of this class could also be reduced quite a bit if it used an array (or arraylist) instead of a treemap. The only issue is the perf of getScopeLevel, but we have such a small number of fixed levels that there probably is no noticeable perf diff using a treemap. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4248254#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...