如何访问类中的类？

public class OuterClass {
    private static int staticVariable = 5;
    private int instanceVariable = 10;
    
    // 静态内部类
    public static class InnerStaticClass {
        public void accessOuterClass() {
            System.out.println("访问外部类的静态变量：" + staticVariable);
            // 静态内部类无法直接访问外部类的实例变量
        }
    }
    
    // 成员内部类
    public class InnerMemberClass {
        public void accessOuterClass() {
            System.out.println("访问外部类的静态变量：" + staticVariable);
            System.out.println("访问外部类的实例变量：" + instanceVariable);
        }
    }
    
    public void outerClassMethod() {
        // 局部内部类
        class LocalInnerClass {
            public void accessOuterClass() {
                System.out.println("访问外部类的静态变量：" + staticVariable);
                System.out.println("访问外部类的实例变量：" + instanceVariable);
            }
        }
        
        LocalInnerClass localInner = new LocalInnerClass();
        localInner.accessOuterClass();
    }
    
    public void accessInnerClasses() {
        InnerStaticClass innerStatic = new InnerStaticClass();
        innerStatic.accessOuterClass();
        
        InnerMemberClass innerMember = new InnerMemberClass();
        innerMember.accessOuterClass();
    }
    
    public static void main(String[] args) {
        OuterClass outer = new OuterClass();
        outer.accessInnerClasses();
    }
}