Classes - The Java Language Specification - page 204

FieldModifier: one of
Annotation public protected private
static final transient volatile
If an annotation a (§ 9.7 ) on a field declaration corresponds to an annotation type T (§ 9.6 ) ,
and T has a (meta-)annotation m that corresponds to java.lang.annotation.Target , then m must
have an element whose value is java.lang.annotation.ElementType.FIELD , or a compile-time er-
ror occurs.
The access modifiers public , protected , and private are discussed in § 6.6 .
It is a compile-time error if the same modifier appears more than once in a field declaration,
or if a field declaration has more than one of the access modifiers public , protected , and private .
If two or more (distinct) field modifiers appear in a field declaration, it is customary,
though not required, that they appear in the order consistent with that shown above in
the production for FieldModifier .
8.3.1.1. static Fields
If a field is declared static , there exists exactly one incarnation of the field, no matter how
many instances (possibly zero) of the class may eventually be created.
A static field, sometimes called a class variable, is incarnated when the class is initialized
(§ 12.4 ) .
A field that is not declared static (sometimes called a non- static field) is called an instance
variable . Whenever a new instance of a class is created (§ 12.5 ), a new variable associated
with that instance is created for every instance variable declared in that class or any of its
superclasses.
Example 8.3.1.1-1. static Fields
Click here to view code image
class Point {
int x, y, useCount;
Point(int x, int y) { this.x = x; this.y = y; }
static final Point origin = new Point(0, 0);
}
class Test {
public static void main(String[] args) {
Point p = new Point(1,1);
Point q = new Point(2,2);