Redian新闻
>
who can help me with this dummy Question??
avatar
who can help me with this dummy Question??# Java - 爪哇娇娃
t*r
1
Parent.java:
public class Parent {
public Parent() {
System.out.println("parent");
}
}
Child.java:
public class Child extends Parent {
public Child() {
System.out.println("child");
}
public static void main(String[] args) {
Child c = new Child();

}
}
java Child, outputs:
parent
child
WHY??
avatar
g*s
2
If you don't call super(xxx) or this(xxx) as the first line of code in a
constructor, Java will automatically insert a call to the default no-
argument superclass constructor super() for you.

【在 t****r 的大作中提到】
: Parent.java:
: public class Parent {
: public Parent() {
: System.out.println("parent");
: }
: }
: Child.java:
: public class Child extends Parent {
: public Child() {
: System.out.println("child");

avatar
g*s
3
If you don't call super(xxx) or this(xxx) as the first line of code in a
constructor, Java will automatically insert a call to the default no-
argument superclass constructor super() for you.

【在 t****r 的大作中提到】
: Parent.java:
: public class Parent {
: public Parent() {
: System.out.println("parent");
: }
: }
: Child.java:
: public class Child extends Parent {
: public Child() {
: System.out.println("child");

avatar
B*N
4
you can use a debugger to step through, which will help you to understand
the instantiation sequence of every bit, and that will help you to
understand more OO.

【在 t****r 的大作中提到】
: Parent.java:
: public class Parent {
: public Parent() {
: System.out.println("parent");
: }
: }
: Child.java:
: public class Child extends Parent {
: public Child() {
: System.out.println("child");

相关阅读
logo
联系我们隐私协议©2024 redian.news
Redian新闻
Redian.news刊载任何文章,不代表同意其说法或描述,仅为提供更多信息,也不构成任何建议。文章信息的合法性及真实性由其作者负责,与Redian.news及其运营公司无关。欢迎投稿,如发现稿件侵权,或作者不愿在本网发表文章,请版权拥有者通知本网处理。