[Characteristic] Can be used to combined several operations into an atomic operation? [Volatile] Pre-Java 5, no. Atomic get-set of volatiles possible in Java 5. [Synchronized] 
Yes
O b j e c t
N o
Y e s
W h e n y o u e x p l i c i t l y e n t e r / e x i t a s y n c h r o n i z e d b l o c k