What are the ways to implement code reuse besides inheritance?

In addition to inheritance, code reuse in Java can be implemented in the following ways:

• Composition — including objects of other classes as fields and delegating tasks to them. Allows flexible behavior combination.
• Interfaces with default methods (since Java 8) — allow defining method implementations in interfaces that can be reused.
• Utility classes and static methods — common functionality is placed in separate classes with static methods.
• Design patterns — such as strategy, decorator, adapter, help reuse and extend behavior without inheritance.

Example of composition:

class Engine {
    void start() { System.out.println("Engine started"); }
}

class Car {
    private Engine engine = new Engine();
    void start() {
        engine.start();
        System.out.println("Car started");
    }
}