Java modifiers summary

Modifier	Class	Interface	Inner Class	Inner Interface	Variable	Method	Constructor	Free-Floating Block
public	yes	yes	yes	yes	yes	yes	yes	no
protected	no	no	yes	yes	yes	yes	yes	no
none or package or default	yes	yes	yes	yes	yes	yes	yes	yes
private	no	no	yes	yes	yes	yes	yes	no
final	yes	no	yes	no	yes	yes	no	no
abstract	yes	yes/no	yes	yes/no	no	yes	no	no
static	no	no	yes	yes	yes	yes	no	yes
native	no	no	no	no	no	yes	no	no
transient	no	no	no	no	yes	no	no	no
volatile	no	no	no	no	yes	no	no	no
synchronized	no	no	no	no	no	yes	no	yes
strictfp	yes	yes	yes	yes	no	yes	yes	no

Points:

• all access modifiers can be used to classes and members except for protected and private which cannot be used to outer classes and interfaces
  


• free-floating block cannot have access modifiers. it can only use static or synchronized
  


• constructors can only use access modifiers and strictfp
  


• native is only for methods
  


• transient and volatile are only for variables. Transient indicates that it is not serializable. Volatile indicates that it can be modified simultaneously by many threads.
  


• synchronized can only be used on methods or free-floating blocks
  


• strictfp can't be used on variables or free-floating blocks
  
  Using strictfp ensures that you get the same result of floating-point expressions across multiple platforms. But it may also result to overflow or underflow hence the expression, "Write-Once-Get-Equally-Wrong-Results-Everywhere". If you don't use strictfp, JVM can calculate floating-point expressions however it want and thus could produce more accurate results.