如果constructor里调用了一个成员方法，这个方法被子类override了，当初始化一个子类实例时，父类的构造函数被的调用，此时父类构造函数的上下文里调用的成员方法，是父类的实现还是子类的实现？ 你能不用运行代码，就能准确说出这些语句会打印什么出来呢？

ABAP

class ZCL_SUPER definition  public  create public .public section.  methods CONSTRUCTOR .  methods SET_I    importing      !IV_I type INT4 .protected section.private section.  data MV_SUPER type INT4 .ENDCLASS.CLASS ZCL_SUPER IMPLEMENTATION.  method CONSTRUCTOR.    me->set_i( 100 ).  endmethod.  method SET_I.    me->mv_super = iv_i.  endmethod.ENDCLASS.class ZCL_SUB definition  public  inheriting from ZCL_SUPER  final  create public .public section.  methods PRINT .  methods SET_I    redefinition .protected section.private section.  data MV_SUB type I value 1 ##NO_TEXT.ENDCLASS.CLASS ZCL_SUB IMPLEMENTATION.  method PRINT.    WRITE: / ' sub:' , mv_sub.  endmethod.  METHOD set_i.    super->set_i( iv_i = iv_i ).    me->mv_sub = iv_i.    WRITE: / 'mv_sub assigned by: ' , iv_i.  ENDMETHOD.ENDCLASS.

测试：

NEW zcl_sub( )->print( ).

测试结果：sub: 1

Java

public class SuperClass {    private int mSuperX;    public SuperClass() {        setX(99);    }    public void setX(int x) {        mSuperX = x;    }}public class SubClass extends SuperClass {    private int mSubX = 1;    public SubClass() {}    @Override    public void setX(int x) {        super.setX(x);        mSubX = x;        System.out.println("SubX is assigned " + x);    }    public void printX() {        System.out.println("SubX = " + mSubX);    }}

test:

public static void main(String[] args) {        SubClass sc = new SubClass();        sc.printX();    }

测试结果：

JavaScript

function SuperClass(){    this.setX(99);}SuperClass.prototype = {    mSuperX : 0,    setX : function(x){         this.mSuperX = x;    }};function SubClass(){      SuperClass.call(this);      this.mSubX = 1;}  SubClass.prototype = new SuperClass();  SubClass.prototype.setX = function(x){        SuperClass.prototype.setX(x);        this.mSubX = x;        console.log("SubX is assigned " + x);};SubClass.prototype.print = function(){    console.log("SubX: " + this.mSubX);}

test:

var sub = new SubClass();sub.print();

测试结果:

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