<?php
/**
 * Created by PhpStorm.
 * User: 27394
 * Date: 2016/11/15
 * Time: 8:35
 */
class A{
    public static function __contruct(){
        echo __CLASS__."A";
    }
    public static function init(){
        return new self();
    }
}
class B{
    public static function __contruct(){
        echo
 
 __CLASS__."B";
    }
    public static function init(){
        return new static();
    }
}
class C extends A{
    public static function __contruct(){
        echo __CLASS__."C";
    }
}
class D extends B{
    public static function __contruct(){
        echo __CLASS__."D";
    }
}
class E extends
 
 A{
    public static function __contruct(){
        echo __CLASS__."E";
    }
    public static function init(){
        return new self();
    }
}
class F extends B{
    public static function __contruct(){
        echo __CLASS__."F";
    }
    public static function init(){
        return new static
 
();
    }
}
var_dump(C::init());// new self()
// object(A)#1 (0) { } self 代表 使用它的那個類
var_dump(D::init());// new static()
// object(D)#1 (0) { } static 代表當前自己的類
var_dump(E::init());
//object(E)#1 (0) { }
var_dump(F::init());
//object(F)#1 (0) { }