http://soft6.com/tech/4/46644.html
构造一个类时,它的父类和成员变量所属类的构造函数都会被自动执行
程序:
public class Test {
public static void main(String[] args) {
Child child = new Child();
}
}
class Parent {
Parent() {
System.out.println("to construct Parent.");
}
}
class Child extends Parent {
Child() {
System.out.println("to construct Child.");
}
Delegatee delegatee = new Delegatee();
}
class Delegatee {
Delegatee() {
System.out.println("to construct Delegatee.");
}
}
运行结果:
to construct Parent.
to construct Delegatee.
to construct Child.