Oracle is proposing an update to the Java Virtual Machine to allow for direct-value class types, a modernization required by the advent of multicore processors. There is no schedule for when the changes might appear in the JVM.
The changes to the JVM specification would support a prototype of value classes—classes for which primitive-like non-reference value instances can be created and acted upon. “The proposals for value types in Java are about giving developers the alternative to give up identity and polymorphism so that the runtime can represent the underlying data in a way which is both far more compact and much better suited for processing in bulk operations,” said Georges Saab, Oracle’s vice president of software development in the Java platform group.