设计模式问题：单例模式的静态内部类，getInstance方法为什么要final

Question

单例模式的静态内部类，get方法为什么要final

public class Singleton {
    // 静态内部类在 JVM 中是唯一的
    private static class SingletonHoder {
        private static final Singleton INSTANCE = new Singleton();
    }
    private Singleton() {
        // 构造
    }
    private static final Singleton getInstance() {
        return SingletonHoder.INSTANCE;
    }
}

Answer 1

https://blog.csdn.net/qq_37132495/article/details/121860501
https://blog.csdn.net/past__time/article/details/82978152