Implementing Interfaces and Extending Classes

Many Java APIs expect you to pass an object that implements an interface (callbacks, listeners, Runnable, Comparator, etc.). In Clojure, the common tools are:

• reify to implement one or more interfaces (and sometimes abstract methods) inline
• proxy when you need to extend a concrete class or override methods dynamically

For Java engineers, think of these as “anonymous class” replacements, but with less ceremony. The key practice is to keep these implementations small and focused—treat them as adapters at the boundary, not as your main program design.

In this section

• Defining Classes with `gen-class` in Clojure for Java Interoperability
  Explore how to define classes in Clojure using `gen-class` for seamless Java interoperability. Learn to specify methods, handle constructors, and create classes that can be instantiated from Java code.
• Overriding Methods in Clojure: A Guide for Java Developers
  Learn how to override methods in Clojure when extending Java classes or implementing interfaces, with examples and comparisons to Java.
• Compiling and Using Generated Classes: A Guide for Java Developers
  Learn how to compile Clojure code using `gen-class` into Java bytecode, package it, and use the generated classes in Java applications.