java链表的基本使用 （购物车）代码
package test;
interface ILink<E>{
public void add(E e);//添加链表数据
public int size();//返回链表长度
public boolean isEmpty();//判断链表是否为空
public Object [] toArray();//返回集合数据
public E get(int index);//返回指定索引的数据
public void set(int index,E data);//修改值
public boolean contains(E data);//判断指定数据是否存在
public void remove(E data);//删除指定数据
public void clean();//清空
}
class LinkImpl<E> implements ILink<E>{
private class Node{//保存节点的数据关系
private E data;
private Node next;//保存下一个引用
private Node(E data) {
this.data=data;
}
//第一次调用
public void addNode(Node newNode) {
//保存新的Node数据
if(this.next==null) {
this.next =newNode;
}else {
this.next.addNode(newNode);
}
}
public void toArrayNode() {
LinkImpl.this.returnData [LinkImpl.this.foot ++]=this.data;
if(this.next!=null) {
this.next.toArrayNode();
}
}
public E getNode(int index) {
if(LinkImpl.this.foot ++ ==index) {
return this.data;
}
else {
return this.next.getNode(index);
}
}
public void setNode(int index,E data) {
if(LinkImpl.this.foot ++ ==index) {
this.data=data;
}
else {
this.next.getNode(index);
}
}
public boolean containsNode(E data) {
if(this.data.equals(data)) {
return true;
}
else{
if(this.next==null) {
return false;
}else {
return this.next.containsNode(data);
}
}
}
public void removeNode(Node previous,E data) {
if(this.data.equals(data)) {
previous.next=this.next;
}else {
if(this.next!=null) {
this.next.removeNode(this, data);
}
}
}
}
private Node root;
private int count;//增加数据
private int foot;
private Object[] returnData;
public void add(E e) {
if(e==null) { return ;
}else {
Node newNode = new Node(e);//创建新节点
if(this.root==null) {
this.root=newNode;
}
else {
this.root.addNode(newNode);
}
this.count++;
}
}
@Override
public int size() {
// TODO Auto-generated method stub
return this.count;
}
@Override
public boolean isEmpty() {
//this.count==0
return this.root==null;
}
@Override
public Object[] toArray() {
if(this.isEmpty()) {
return null;
}
this.foot=0;
this.returnData=new Object[this.count];
this.root.toArrayNode();
return this.returnData;
}
@Override
public E get(int index) {
if(index>this.count) {
return null;
}
this.foot=0;
return this.root.getNode(index);
}
@Override
public void set(int index, E data) {
if(index>=this.count) {
return ;
}
this.foot=0;
this.root.setNode(index, data);
}
@Override
public boolean contains(E data) {
if(data==null) {
return false;
}
return this.root.containsNode(data);
}
@Override
public void remove(E data) {
if(this.contains(data)) {
if(this.root.data==data) {
this.root=this.root.next;
}else {
this.root.next.removeNode(this.root, data);
}
this.count--;
}
}
@Override
public void clean() {
this.root=null;
this.count=0;
}
}
interface IGoods{//商品标准
public String getName();
public double getPrice();
}
interface IShopCar{//购物车的标准
public void add(IGoods goods);//添加商品信息
public void delete(IGoods goods);//删除商品
public Object[] getAll();//获得购物车中的全部商品信息
}
class shopCarImpl implements IShopCar{
private ILink<IGoods> allGoodses =new LinkImpl<IGoods>();
@Override
public void add(IGoods goods) {
this.allGoodses.add(goods);
}
@Override
public void delete(IGoods goods) {
this.allGoodses.remove(goods);
}
@Override
public Object[] getAll() {
// TODO Auto-generated method stub
return this.allGoodses.toArray();
}
}
class Cashier{//收银台
public IShopCar shopcar;
public Cashier(IShopCar shopcar) {
this.shopcar=shopcar;
}
public double allPrice() {//计算总价
double sum=0.0;
Object[] all = this.shopcar.getAll();
for(Object obj:all) {
IGoods goods=(IGoods)obj;
sum+=goods.getPrice();
}
return sum;
}
public int allCount() {
return this.shopcar.getAll().length;
}
}
class Book implements IGoods{
private String name;
private double price;
public Book(String name,double price) {
this.name=name;
this.price=price;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
public boolean equals(Object obj) {
if(obj==null) {
return false;
}
if(this==obj) {
return true;
}
if(!(obj instanceof Book)) {
return false;
}
Book book=(Book)obj;
return this.name.equals(book.name)&&
this.price==book.price;
}
public String toString() {
return "【图书信息】:name="+this.name
+"price="+this.price;
}
}
class Bag implements IGoods{
private String name;
private double price;
public Bag(String name,double price) {
this.name=name;
this.price=price;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
public boolean equals(Object obj) {
if(obj==null) {
return false;
}
if(this==obj) {
return true;
}
if(!(obj instanceof Book)) {
return false;
}
Bag bag=(Bag)obj;
return this.name.equals(bag.name)&&
this.price==bag.price;
}
public String toString() {
return "【背包信息】:name="+this.name
+"price="+this.price;
}
}
public class Test1 {
public static void main(String[] args) throws Exception {
IShopCar car = new shopCarImpl();
car.add(new Book("java开发", 40));
car.add(new Book("Oracle",24));
car.add(new Bag("小熊背包", 88));
Cashier cashier = new Cashier(car);
System.out.println(cashier.allPrice());
}
}
