java - 谁能解释下为什么输出是1,0吗

Question

class Singleton{
    private  static Singleton instance=new Singleton();
    public static int count;
    public static int count1=0;
    private Singleton(){
        count++;
        count1++;
        
    }
    public static Singleton  getInstance(){
        return instance;
    }
    
}
public class SingleTonDemo {
    public static void main(String[] args) {
        Singleton  instance=Singleton.getInstance();
        System.out.println(instance.count); //1
        System.out.println(instance.count1);//0
    }

Answer 1

Kerana tertib permulaan pembolehubah anda.

1. mencipta objek Singleton Pada masa ini, count dan count1 kedua-duanya 1

   .

   private static Singleton instance = new Singleton();

2. Permulaan statikcount1, di sini count1 ditugaskan kepada 0

   public static int count1 = 0;

3. Jika anda mahu 2, anda perlukan 1. Hanya letakkan instance pemula di bawah count1.

   public static int count;
   public static int count1 = 0;
   private static Singleton instance = new Singleton();