Java supporters want to build an incubator project to explore the language features of advanced virtual machines and software development platforms. The project Valhalla Hall, presented as an openjdk mailing list, will be hatched and other eigenvalue types, general specialization, enhanced volatiles, and concrete imitations. The features being considered are considered long-term, and it is unlikely that any of them will be included in Java 9. It will have come in 2016 and Java 8 will be released in March.
The main items of Valhalla Hall include value types and specializations, based on background materials in the Valhalla Palace project, designed to deal with boxing problems. Boxed integers require more memory and need to dereference the payload, which usually leads to the idea of ​​caching small aggregates that are custom numeric types and complex or uint128. Tuples, algebraic data types, can abstract the benefits of an object while maintaining the performance characteristics of the primitive.
The Valhalla project needs to work at multiple levels, including type systems, languages, virtual machines, and libraries. The project's expected approach is to start at the virtual machine level, use well-defined semantics and underlying support, and also be organized by the Java JVM and other languages, and then integrate these into the Java language.