Java Modifier Summary – 247AppsStudio Blog

Modifier	Used on	Meaning
abstract	class interface method	Contains unimplemented methods and cannot be instantiated. All interfaces are abstract. Optional in declarations No body, only signature. The enclosing class is abstract
final	class method field variable	Cannot be subclassed Cannot be overridden and dynamically looked up Cannot change its value. static final fields are compile-time constants. Cannot change its value.
native	method	Platform-dependent. No body, only signature
none(package)	class interface member	Accessible only in its package Accessible only in its package Accessible only in its package
private	member	Accessible only in its class(which defines it).
protected	member	Accessible only within its package and its subclasses
public	class interface member	Accessible anywhere Accessible anywhere Accessible anywhere its class is.
strictfp	class method	All methods in the class are implicitly strictfp. All floating-point computation done is strictly conforms to the IEEE 754 standard. All values including intermediate results must be expressed as IEEE float or double values. It is rarely used.
static	class method field initializer	Make an inner class top-level class A class method, invoked through the class name. A class field, invoked through the class name one instance, regardless of class instances created. Run when the class is loaded, rather than when an instance is created.
synchronized	method	For a static method, a lock for the class is acquired before executing the method. For a non-static method, a lock for the specific object instance is acquired.
transient	field	Not be serialized with the object, used with object serializations.
volatile	field	Accessible by unsynchronized threads, very rarely used.

All Possible Combinations of Features and Modifiers

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