What's invokedynamic and how do I use it?

java reflection jvm invokedynamic
David K. picture David K. · Jul 10, 2011 · Viewed 49.7k times · Source

I keep hearing about all the new cool features that are being added to the JVM and one of those cool features is invokedynamic. I would like to know what it is and how does it make reflective programming in Java easier or better?

Answer

Ernest Friedman-Hill picture Ernest Friedman-Hill · Jul 10, 2011

It is a new JVM instruction which allows a compiler to generate code which calls methods with a looser specification than was previously possible -- if you know what "duck typing" is, invokedynamic basically allows for duck typing. There's not too much you as a Java programmer can do with it; if you're a tool creator, though, you can use it to build more flexible, more efficient JVM-based languages. Here is a really sweet blog post that gives a lot of detail.

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