We're still mixing merging and parsing logic, which to me looks like an unsolvable puzzle. What's the function of the override (NamedMetaDataWithDescriptionGroupWithOverride.data)? Either it's for holding data from the jboss xml parse or it's for referring to the override. IMHO it can't be both. The code now creates a StackOverflow in JBossEnterpriseBean.setDescriptionGroup. (ensureOverride returns a new instance of the same class and calls setDescriptionGroup.) I have changed this part, but as long as the above question is unanswered the solution is by definition wrong. Another thing is the merge method: the current use of the merge is contradicting the implementation. MergeUtil.merge: JBossMetaData merged = new JBossMetaData(); | merged.merge(jboss, spec); | merged.setOverridenMetaData(spec); | return merged; vs for example IdMetaDataImpl: public void merge(IdMetaDataImpl merged, IdMetaDataImpl original) | { | ... | if (id != null) | merged.setId(id); | else if (original.id != null) | merged.setId(original.id); | } where merged is the target. I would rather see this as target (as in MergeUtil) and have the following signature: interface Mergable<M> | void merge(M original, M override); Or maybe only a one-way merge: interface Mergable<M> | void merge(M override); Because the default (non-performant) code is always: void merge(M original, M override) | { | merge(original); | merge(override); | } View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4097391#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...