Acces to private field from nested class when the type of reference is a generic type variable with upper bound of outer class

[maurizio cimadamore]

Yep - that's intentional - it's listed in the compatibility notes of the 
JDK 7 release [1].
In general accessing private members of a type-variable is not sound 
(note that O could be instantiate by a subclass of Outer in which the 
field would not be accessible).

[1] - 
http://www.oracle.com/technetwork/java/javase/compatibility-417013.html#source

Maurizio


On 07/10/2011 20:29, Peter Levart wrote:
> This code compiles with latest JDK 6 javac:
>
> package test;
>
> public class Outer
> {
>      private int outerField;
>
>      public Outer(int outerField)
>      {
>          this.outerField = outerField;
>      }
>
>      public static class Inner<O extends Outer>
>      {
>          public int getOuterField(O outer)
>          {
>              return outer.outerField;
>          }
>      }
>
>      public static void main(String[] args)
>      {
>          Outer outer = new Outer(12);
>          Inner<Outer>  inner = new Inner<Outer>();
>          System.out.println(inner.getOuterField(outer));
>      }
> }
>
>
> ... but refuses to compile with JDK 7 javac (release or latest 7u2-b08 prerelease), giving the
> following compilation failure:
>
> src/test/Outer.java:16: error: outerField has private access in Outer
>              return outer.outerField;
>                          ^
>
> even if tried with -source 1.6 -target 1.6 options.
>
> Is this intentional or a bug?
>
>
> Regards, Peter