FULL PRODUCT VERSION :
java version "1.8.0_74"
Java(TM) SE Runtime Environment (build 1.8.0_74-b02)
Java HotSpot(TM) 64-Bit Server VM (build 25.74-b02, mixed mode)
ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]
A DESCRIPTION OF THE PROBLEM :
The problem seems to manifest itself while using a public method reference of a package-private class through a public subclass from another package.
Please consider the following two classes which reside in "package1":
-----------
Foo.java
-----------
package package1;
abstract class Foo {
public String getFoo() {
return "foo";
}
}
-----------
Bar.java
-----------
package package1;
public class Bar extends Foo {
public String getBar() {
return "bar";
}
}
Now please consider the following class which reside in "package2":
--------------------
Something.java
--------------------
package package2;
import java.util.stream.Stream;
import package1.Bar;
public class Something {
public static void main(String[] args) {
System.out.println(new Bar().getFoo());
// "foo"
Stream.of(new Bar()).map(Bar::getFoo).forEach(System.out::println);
// IllegalAccessError
}
}
As you can see from the comments in the code:
- directly accessing the public method "getFoo" of the package-private class "Foo" through
its subclass "Bar" from the "package2" does not result in any error;
- using a method reference of the public method "getFoo" of the package-private class "Foo" through its subclass "Bar" in the "package2" results in an IllegalAccessError.
The problem seems to be very similar to the following:
https://bugs.openjdk.java.net/browse/JDK-8029707
REPRODUCIBILITY :
This bug can be reproduced always.