8.3.3

Examples of Field Declarations

CLASSES

}

void printV() {

System.out.println((super.v + Frob.v)/2);

}

}

It compiles and prints:

2.5

Even if two distinct inherited fields have the same type, the same value, and

are both

final

, any reference to either field by simple name is considered ambig 

uous and results in a compile time error. In the example:

interface Color { int RED=0, GREEN=1, BLUE=2; }

interface TrafficLight { int RED=0, YELLOW=1, GREEN=2; }

class Test implements Color, TrafficLight {

public static void main(String[] args) {

System.out.println(GREEN);

//

compile time error

System.out.println(RED);

//

compile time error

}

}

it is not astonishing that the reference to

GREEN

 should be considered ambiguous,

because class

Test

 inherits two different declarations for

GREEN

 with different

values. The point of this example is that the reference to

RED

 is also considered

ambiguous, because two distinct declarations are inherited. The fact that the two

fields named

RED

 happen to have the same type and the same unchanging value

does not affect this judgment.

8.3.3.4

Example: Re inheritance of Fields

If the same field declaration is inherited from an interface by multiple paths, the

field is considered to be inherited only once. It may be referred to by its simple

name without ambiguity. For example, in the code:

public interface Colorable {

int RED = 0xff0000, GREEN = 0x00ff00, BLUE = 0x0000ff;

}

public interface Paintable extends Colorable {

int MATTE = 0, GLOSSY = 1;

}

class Point { int x, y; }

class ColoredPoint extends Point implements Colorable {

. . .

}

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