Yes, and the collaboration with Sun heavily influenced how Java ended up looking. Besides interfaces (protocols), the Java runtime has plenty of Objective-C in

Yes, and the collaboration with Sun heavily influenced how Java ended up looking. Besides interfaces (protocols), the Java runtime has plenty of Objective-C influences, even JAR files are similar to bundles. Also as I mention in another comment, J2EE started as an Objective-C framework, later rewriten into Java, as OpenSTEP efforts ramped down.