Ah, yeah, I remember discussion about this, but didn't know about its result (I'm not active Java developer for some time now). Anyway, I think you've got an id

Ah, yeah, I remember discussion about this, but didn't know about its result (I'm not active Java developer for some time now). Anyway, I think you've got an idea - immutability assumption may be pretty useful and improve performance in some cases, not decrease it (if you use it correctly, of course).