History
The Java Virtual Machine currently has no built-in support for dynamically typed languages:
- The existing JVM instruction set is statically typed.
- JVM has limited support for dynamically modifying existing classes and methods. It currently works only in a debugging environment.
JSR 292 (Supporting Dynamically Typed Languages on the Java Platform) proposes to:
- add a new
invokedynamicinstruction at the JVM level, to allow method invocation relying on dynamic type checking, - to be able to change classes and methods at runtime dynamically in a production environment.
Following the success of the JRuby Java implementation, the Da Vinci project was started at the end of January 2008. The capabilities experimented by Da Vinci are planned to be added to Java 7. It aims to prototype this JSR, but also other lower-priority extensions. The first working prototype, developed as a patch on OpenJDK, was announced and made available on end of August 2008.
Since then, the JRuby team has successfully wired dynamic invocation in their codebase. Dynamic invocation shipped with the 1.1.5 release, and will be disabled on JVMs without invokedynamic capabilities.
Since then, part of the project has already been integrated in the upcoming JDK 7 codebase. and integrated in the Java 7 release.
Read more about this topic: Da Vinci Machine
Famous quotes containing the word history:
“America is the only nation in history which miraculously has gone directly from barbarism to degeneration without the usual interval of civilization.”
—Georges Clemenceau (1841–1929)
“The history of the world is the record of the weakness, frailty and death of public opinion.”
—Samuel Butler (1835–1902)
“Every member of the family of the future will be a producer of some kind and in some degree. The only one who will have the right of exemption will be the mother ...”
—Ruth C. D. Havens, U.S. suffragist. As quoted in History of Woman Suffrage, vol. 4, ch. 13, by Susan B. Anthony and Ida Husted Harper (1902)