Lambda vs anon class optimization effect on CHA

[Vitaly Davidovich]

Hi all,

Suppose we have the following classes and code:

public abstract class Foo {
    public static java.util.Supplier<Foo> null() {
        return () -> Null.INSTANCE;

    }

   // some abstract methods
}

public final class Impl extends Foo {}

public final class Null extends Foo {
      public static final Null INSTANCE = new Null();

}

It seems that the lambda in null(), even when not invoked, causes Null to
be loaded and single-class CHA optimization is disabled.  If I change
null() to use an anon class:

public static java.util.Supplier<Foo> null() {
     return new Supplier<Foo>() {
          public Foo get() { return Null.INSTANCE; }
          }
      };
}

Then CHA kicks in.  Keep in mind that the code I'm running never invokes
null() and only instantiates Impl, so the expectation is that Null would
not load (and disable the single impl CHA optimization).

My understanding was that the lambda in null() would have a bootstrap
method that invokes the lambda metafactory to actually bind the call to the
synthetic static method that's generated, which in turn actually references
Null.INSTANCE (and would cause the class to load).  However, I'm clearly
missing or misunderstanding something.

Would anyone be able to explain the above situation? Is that expected? Let
me know if you need more info.

Thanks
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