我在一個構(gòu)造方法中調(diào)用第二個自身的構(gòu)造方法,第二個自身構(gòu)造方法中又包含一個super(),那么想知道在第一個自身構(gòu)造方法中有沒有隱式的super(),父類對象應(yīng)該是優(yōu)先于子類對象在堆內(nèi)存里面出現(xiàn)的吧?最后究竟創(chuàng)建了幾個父類對象class Person { ?private String name; ?private String location; ?Person(String name) { ? ?this.name = name; ? ?location = "beijing"; ?} ?Person(String name,String location) { ? ?this.name = name; ? ?this.location = location; ?} ?public String info() { ? ?return ? ? ?"name: "+name+ ? ? ?" location: "+location; ?}}class Student extends Person { ? ?private String school; ? ?Student(String name, String school) { ? ? ? ?this(name,"beijing", school); ? ?} ? ?Student(String n,String l ,String school) { ? ? ? ?super(n,l); ? ? ? ?this.school = school; ? ?} ? ?public String info() { ? ? ? ?return super.info()+ ?" school: "+school; ? ?}}public class TestTeacher { ? ?public static void main(String[] args) { ? ?Student s1 = new Student("C","S1"); ? ? ? System.out.println(s1.info()); ? ?}}
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android開發(fā)學(xué)習(xí)視頻
TA貢獻4條經(jīng)驗 獲得超3個贊
Student(n, s)這個構(gòu)造器里顯式調(diào)用this()，抑制隱式super()，追溯到Student(n, l, s)里，沒有顯式this()調(diào)用，則隱式調(diào)用super()，即Person(n, l)
在以上三個構(gòu)造器里添加打印語句，結(jié)果如下：
Person(n, l) established
Student(n, l, s) established
Student(n, s) established
調(diào)用順序一目了然
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