I think we are butting up against JarFile implementation details here. Wouldn't it be better to get InputStream support into truezip? The reading the entry contents into memory is something I had to do for nested jars elements. We are essentially pulling all jar contents into memory. I would think its more of a startup time/memory issue than performance. We won't be able to lazily read entry contents with the JarFile. Maybe we can with truezip, although hopefully its not needed. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3980832#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...