This is a correction to 4531312:

As pointed out by the Java Spec Report,
http://www.ergnosis.com/java-spec-report/java-language/jls-8.8.5.1-d.html,
it is legal to reference enclosing types in an explicit constructor invocation.
 For example, this compiles successfully with javac:

$ cat C.java
class C {
  C(Object o) {}
  private class Middle extends C {
    Middle(int i) {
      super(null);
    }
    Middle() {
      super(C.this.new Middle(1).new Inner(){});
    }
    class Inner {}
  }
}
$ javac C.java
$

However, remove the reference to C.this, and the compiler throws up its hands.

$ cat C.java
class C {
  C(Object o) {}
  private class Middle extends C {
    Middle(int i) {
      super(null);
    }
    Middle() {
      super(/*C.this.*/new Middle(1).new Inner(){}); // only this line changed
    }
    class Inner {}
  }
}
$ javac C.java
C.java:8: cannot reference this before supertype constructor has been called

      super(/*C.this.*/new Middle(1).new Inner(){}); // only this line changed
                       ^
1 error
$

This goes against JLS 15.9.2: Middle is an inner member class, the class
instance creation expression is unqualified, so bullet 3.1.2 applies: the
innermost class O which contains Middle as a member is C, so the enclosing
instance i should be C.this, and the example should compile identically to the
previous example.