Defender methods and compatibility

[Paul Benedict]

Too bad the JDK can't be configured at run-time to resolve the default
method implementations according to how *I* want it. Must it be
specified in the class file? Perhaps it could be done as an SPI or
META-INF external configuration. That way, you let application
designers determine their defaults for their own programs (and not the
original interface writer). Quite frankly, I sometimes think this
extension/default thing is a very weak (and awkward) mix-in
implementation. If I could control what implementation to use, that
beats any solution provided so far. The JDK could come with a default
mix-in implementation, but let me determine how to customize it.