Another ReadOnlyException when setValue on a CustomField

My problem is fairly similar to
but the solution doesn’t work for me because I don’t even get as far.

The problem is that I have a CustomField which throws a
when I try to set a value on it. I never ever set the field read-only so this is very puzzling. When I print out the read-only state of both the
and the underlying
, they come back true. Even after is explicitly

In contrast to the linked problem the field doesn’t even try to set the value in the property but the internal read-only check already fails:

Caused by:$ReadOnlyException at com.vaadin.ui.AbstractField.setValue( at com.vaadin.ui.AbstractField.setValue( at com.example.component.SomeDialog$3.valueChange( How can the field be read-only if I never set it? And how can it refuse to be made writable?

The biggest problem of them all is that this only happens on our production server. Not dev, not test. So it’s very difficult to debug.

It seems this was an OpenJDK 7 bug. After updating to the current version (1.7.0_79) it works.