java 子类、父类中静态代码块、字段，非静态代码块、字段以及构造函数的初始化顺序和次数

public class Animal {

        Sing s1=new Sing(1,"animal\tnot static field");
        static Sing s2=new Sing(2,"animal\tstatic field");
        static Sing s3;
        Sing s4;
        Sing s5;
        
        static{
            s3=new Sing(3,"animal\tstatic code area");
        }
        
        {
            
            s4=new Sing(4,"animal\tnot static code area");
        }
        
        Animal(){
            s5=new Sing(5,"animal\tconstructor");
        }
    }

public class Cat extends Animal {
    Sing s1=new Sing(1,"cat\t\tnot static field");
    static Sing s2=new Sing(2,"cat\t\tstatic field");
    static Sing s3;
    Sing s4;
    Sing s5;
    
    static{
        s3=new Sing(3,"cat\t\tstatic code area");
    }
    
    {
        
        s4=new Sing(4,"cat\t\tnot static code area");
    }
    
    Cat(){
        s5=new Sing(5,"cat\t\tconstructor");
    }
}

public class Sing {
    Sing(int mark,String flag){
        System.out.println(mark+" "+flag);
    }
}

public class Runner {

    public static void main(String[] args) {
        System.out.println("+++++++++++++++++++++first+++++++++++++++++++++++++++++");
        new Cat();
        System.out.println("+++++++++++++++++++++second++++++++++++++++++++++++++++");
        new Cat();
    }
}