Padding is possible with today&#x27;s java (at least Hotspot), although it&#x27;s ugly and relies on Hotspot&#x27;s existing layout implementation.<p>Yes, you can group but as I mentioned in the other reply, you get &quot;blob&quot; granularity&#x2F;control.  This is unlikely to be an issue for a value type instance itself, but say you want to have multiple value types (each with several fields) embedded into a heap allocated object.  Assume this total embedded blog spans multiple cachelines, but you have clustered access patterns.  So you&#x27;ve grouped some data together into value types, but you have no control over how that will be laid out in the &quot;host&quot; object.<p>Again, I&#x27;m happy that Oracle will be adding value types -- they will definitely help.  I contend, however, that calling it &quot;layout control&quot; is a slight stretch in the general sense; it&#x27;s perhaps fair to call it that when comparing against today&#x27;s java, but not against languages that allow explicit field-by-field layout (along with padding, alignment, etc).