CLASSES

Field Declarations

8.3

type

Point3d

 cannot be referred to outside package

morePoints

. The declaration

of the field

z

 as

public

 is not useless, however. If there were to be, in package

morePoints

, a

public

 subclass

Point4d

 of the class

Point3d

:

package morePoints;

public class Point4d extends Point3d {

public int w;

public void move(int dx, int dy, int dz, int dw) {

super.move(dx, dy, dz); w += dw;

}

}

then class

Point4d

 would inherit the field

z

, which, being

public

, could then be

accessed by code in packages other than

morePoints

, through variables and

expressions of the

public

 type

Point4d

.

8.3   Field Declarations

Poetic fields encompass me around,

And still I seem to tread on classic ground.

 Joseph Addison (1672 1719),

A Letter from Italy

The variables of a class type are introduced by

field declarations

:

FieldDeclaration:

FieldModifiers

opt

Type VariableDeclarators

 ;

VariableDeclarators:

VariableDeclarator

VariableDeclarators

 ,

VariableDeclarator

VariableDeclarator:

VariableDeclaratorId

VariableDeclaratorId

 =

VariableInitializer

VariableDeclaratorId:

Identifier

VariableDeclaratorId

 [ ]

VariableInitializer:

Expression

ArrayInitializer

The

FieldModifiers

 are described in  8.3.1. The

Identifier

 in a

FieldDeclarator

may be used in a name to refer to the field. The name of a field has as its scope

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