Implementation Inheritance: Extends

extends

• Because of extends, RotatingSLList inherits all members of SLList:
• All instance and static variables. （注意public, private, protected的区别）
• All methods.
• All nested classes.
• Constructors are not inherited.

super

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public class VengefulSLList<Item> extends SLList<Item> {
private SLList<Item> deletedItems;
	public VengefulSLList() {
       deletedItems = new SLList<Item>();
	}
  
	@Override
	public Item removeLast() {
    		Item oldBack = super.removeLast();
    		deletedItems.addLast(oldBack);
    		return oldBack;
	}
 
	public void printLostItems() {
    		deletedItems.print();
	}
}

注意没有super.super的情况

constructor

Object class

Encapsulation

Module

Module: A set of methods that work together as a whole to perform some task or set of related tasks.

Implementation Inheritance Breaks Encapsulation

注意private 还有 反复自我调用↓

Type Checking and Casting

子类赋值给基类可以，反之不行

Dynamic Method Selection and Casting Puzzle

Higher Order Functions (A First Look)

执行类似f(f(x))的操作 Java7及之前不能使用函数指针，考虑实体化一个函数对象

Java8及其以后： 一张图总结继承