When should I use inner classes in Java?

When should I use inner classes in Java?

Inner classes in Java are useful when you want to logically group classes that are only used in one place, increase encapsulation, or create a more readable code structure.

Can you give me an example of an inner class?

Sure! Here's a simple example:

class OuterClass {
    private String outerField = "Outer field";
    
    class InnerClass {
        void display() {
            System.out.println(outerField);
        }
    }
}

In this example, InnerClass can access the outerField of OuterClass.

What are the different types of inner classes?

There are four types of inner classes in Java: non-static inner classes, static nested classes, local classes (defined within a method), and anonymous classes.

Are there any downsides to using inner classes?

Yes, inner classes can increase complexity and make the code harder to understand if overused. They can also lead to memory leaks if not handled properly.