Java Nested Classes: A closer look at inner classes in Java

In Java programming, inner classes are a very useful concept that allow one class to be defined within another class. A nested class is a special kind of inner class that has its own characteristics and uses. This article will take an in-depth look at nested classes in Java and provide corresponding source code examples.

1. What is a nested class?

A nested class is a class defined inside another class. It can be divided into two types: static nested classes and non-static nested classes. Static nested classes are staticinner classes modified with keywords, while non-static nested classes are not staticmodified with keywords.

2. Static nested classes

Static nested classes are the most common type of nested classes. It is defined like a normal class definition, except that it is inside another class. Static nested classes can be accessed directly through the name of the outer class without creating an instance of the outer class.

Here is a sample code that demonstrates how to define and use static nested classes:

public class OuterClass {
   
    
    
    // 外部类的成员变量和方法
    
    public static class NestedClass {