Monkey-patching in Java

The JVM is an excellent platform for monkey-patching.

Monkey patching is a technique used to dynamically update the behavior of a piece of code at run-time. A monkey patch (also spelled monkey-patch, MonkeyPatch) is a way to extend or modify the runtime code of dynamic languages (e.g. Smalltalk, JavaScript, Objective-C, Ruby, Perl, Python, Groovy, etc.) without altering the original source code.

-- Wikipedia

I want to demo several approaches for monkey-patching in Java in this post.

As an example, …

behavior code dynamic etc groovy instrumentation java javascript languages perl platform python ruby