我知道这个在网上随便都可以搜到一大堆，但是我希望大家自己亲自动手写一下，将自己的代码写在下面

这不是华为面试题么

[Java] 纯文本查看 复制代码

class Single(){
 private static final Single single = new Single();
 private Signel(){
 }
 public static Single getSingle(){
  return single;
 }
}

这个是我写的代码:

[Java] 纯文本查看 复制代码

public class Signale{
private Signale(){}
private static Signale instance=null;
public static synrothized Signale getInstance(){
  if(instance==null)
      instance=new Signale();
   return instance;
}
}

我一直用的：

[Java] 纯文本查看 复制代码

public class SingletonClass {
    
    // 私有内部类
    private static class SingletonClassInstance {
        private static final SingletonClass instance = new SingletonClass();
    }

    public static SingletonClass getInstance() {
        return SingletonClassInstance.instance;
    }

    private SingletonClass() {
    }
}

class Moon{

class Sun{
private static Sun theOne;
private Sun(){}
public static synchronized Sun getInstance(){
  if(theOne == null)
   theOne = new Sun();
  return theOne;
}
}

class Moon{
        private static Moon theOne = new Moon();
        private Moon(){}
        public static Moon getInstance(){
                return theOne;
        }
}