Java: "Dynamic Language Support on the Java Virtual Machine"
A new bytecode and a new linkage mechanism offer better support for dynamically typed languages.
Java Development Kit (JDK) 7
is a prototype of what could be in the next release of Java Platform, Standard Edition (Java SE). JDK 7 introduces several key features to improve the performance, usability, and security of the Java platform. Of particular interest to Java developers is the addition of support for Java Specification Request (JSR) 292.
The addition of a new Java bytecode, invokedynamic, for method invocation, and an accompanying linkage mechanism that makes use of a new construct called a method handle, will enable implementers of compilers for dynamically typed languages such as JRuby and Jython to generate bytecode that runs extremely fast in the Java virtual machine (JVM).
As a result, you should see more of your favorite dynamically typed languages available in the Java ecosystem, along with a performance boost in code generated by dynamically typed language compilers that run in the JVM. This article will help you take advantage of the new invokedynamic Java bytecode instruction for the JVM and the new method handle linkage mechanism.
Full Article: http://www.oracle.com/technology/oramag/oracle/10-may/o30java.html