设计模式第三次作业
- 要求：某商品管理系统的商品名称存储在一个字符串数组中，现需要自定义一个双向迭代器（MyIterator）实现对该商品名称数组的双向（向前和向后）遍历。使用Iterator模式来设计。
类图：
关键类java源码及注释：
public interface abstructIterator {
public void next();
public boolean isLast();
public void previous();
public boolean isFirst();
public String getNext();
public String getPrevious();
}
public interface abstructProduct {
abstructIterator createIterator();
}
public class Product implements abstructProduct{
private Object[] obj={"苹果","梨","橙子","香蕉"};
@Override
public abstructIterator createIterator() {
return new MyIterator();
}
private class MyIterator implements abstructIterator{
private int index1;
private int index2;
public MyIterator() {
index1 = 0;
index2 = obj.length - 1;
}
@Override
public void next() {
if(index1<obj.length){
index1++;
}
}
@Override
public boolean isLast() {
return (index1 == obj.length);
}
@Override
public void previous() {
if (index2>-1) {
index2--;
}
}
@Override
public boolean isFirst() {
return index2==-1;
}
@Override
public String getNext() {
return (String) obj[index1];
}
@Override
public String getPrevious() {
return (String) obj[index2];
}
}
}
public class client {
public static void main(String[] args) {
abstructIterator iterator;
abstructProduct product =new Product();
iterator=product.createIterator();
while (!iterator.isLast()) {
System.out.print(iterator.getNext());
System.out.print(" ");
iterator.next();
}
System.out.println();
while (!iterator.isFirst()) {
System.out.print(iterator.getPrevious());
System.out.print(" ");
iterator.previous();
}
}
}
输出结果：
苹果 梨 橙子 香蕉
香蕉 橙子 梨 苹果
- 要求：某公司欲开发一个基于Windows平台的公告板系统，系统提供主菜单（Menu）其中有菜单项（MenuItem）。通过Menu类的addMenuItem()方法增加菜单项。菜单项的打开方法是click(）,每个菜单项包含一个抽象命令类，具体命令类包括OpenCommand()、CreateCommand()、EditCommand()等，命令类具有一个execute()方法，用于调用公告板系统界面类（BoardScreen()）的open()、create()、edit()）等方法。使用Command模式来设计。
类图：
关键类java源码及注释：
public interface abstructCommand {
public void execute();
}
public class CreateCommand implements abstructCommand{
private BoardScreen bs;
public CreateCommand( BoardScreen bs){
this.bs=bs;
}
@Override
public void execute() {
bs.create();
}
}
public class EditCommand implements abstructCommand{
private BoardScreen bs;
public EditCommand ( BoardScreen bs){
this.bs=bs;
}
@Override
public void execute() {
bs.edit();
}
}
public class OpenCommand implements abstructCommand{
private BoardScreen bs;
public OpenCommand ( BoardScreen bs){
this.bs=bs;
}
@Override
public void execute() {
bs.open();
}
}
public class MenuItem {
private abstructCommand command;
public MenuItem(abstructCommand command){
this.command=command;
}
public void click(){
this.command.execute();
}
}
import java.util.ArrayList;
public class Menu {
private ArrayList<MenuItem> menuItemsList = new ArrayList<MenuItem>();
public void addMenuItem(MenuItem item){
this.menuItemsList.add(item);
}
public void clickMenuItem(int index) {
menuItemsList.get(index).click();
}
}
public class BoardScreen {
public void open(){
System.out.println("open被调用");
}
public void create(){
System.out.println("create被调用");
}
public void edit(){
System.out.println("edit被调用");
}
}
public class client {
public static void main(String[] args) {
Menu menu=new Menu();
BoardScreen bs = new BoardScreen();
abstructCommand oc=new OpenCommand(bs );
MenuItem item1=new MenuItem(oc);
menu.addMenuItem(item1);
abstructCommand cc=new CreateCommand(bs );
MenuItem item2=new MenuItem(cc);
menu.addMenuItem(item2);
abstructCommand ec=new EditCommand(bs );
MenuItem item3=new MenuItem(ec);
menu.addMenuItem(item3);
menu.clickMenuItem(0);
menu.clickMenuItem(1);
menu.clickMenuItem(2);
}
}
输出结果：
open被调用
create被调用
edit被调用
- 要求：某论坛系统欲增加一个虚拟聊天室，允许论坛会员通过该聊天室进行信息交流，普通会员（CommonMember）可以给其他会员发送文本信息，钻石会员（DiamondMember）可以给其他会员发送文本和图片信息。该聊天室可以对不雅字符进行过滤，如“TMD”等字符，还可以对发送图片大小进行控制。使用Mediator模式来设计。
类图：
关键类java源码及注释：
public abstract class abstructChatRoom {
public abstract void addRoom(Member member);
public abstract void sendText(String form,String to,String text);
public abstract void sendImage(String form,String to,String image);
}
import java.util.HashMap;
import java.util.Map;
public class ChatRoom extends abstructChatRoom{
Map<String, Member> map=new HashMap<String,Member>();
@Override
public void addRoom(Member member) {
map.put(member.getName(), member);
member.setAbstructChatRoom(this);
}
@Override
public void sendText(String from, String to, String text) {
Member memberToText=map.get(to);
memberToText.reciveText(from, text);
}
@Override
public void sendImage(String from, String to, String image) {
Member memberToImage=map.get(to);
memberToImage.reciveImage(from, image);
}
}
public abstract class Member {
protected String name;
protected abstructChatRoom abstructChatRoom;
public Member(String name) {
this.name=name;
}
public String getName() {
return name;
}
public abstructChatRoom getAbstructChatRoom() {
return abstructChatRoom;
}
public void setAbstructChatRoom(abstructChatRoom abstructChatRoom) {
this.abstructChatRoom = abstructChatRoom;
}
public abstract void sendText(String to,String Text);
public abstract void sendImage(String to,String Image);
public void reciveText(String from,String Text){
System.out.println(this.name+"接收来自"+from+"的文本："+Text);
}
public void reciveImage(String from,String Image){
System.out.println(this.name+"接收来自"+from+"的图片："+Image);
}
}
public class DiamondMember extends Member{
public DiamondMember(String name){
super(name);
}
@Override
public void sendText(String to, String Text) {
System.out.println(this.name+"向"+to+"发送的文本："+Text);
super.abstructChatRoom.sendText(this.name, to, Text);
}
@Override
public void sendImage(String to, String Image) {
System.out.println(this.name+"向"+to+"发送的图片："+Image);
super.abstructChatRoom.sendImage(this.name, to, Image);
}
}
public class CommonMember extends Member {
public CommonMember(String name){
super(name);
}
@Override
public void sendText(String to, String Text) {
System.out.println(this.name+"向"+to+"发送的文本："+Text);
super.abstructChatRoom.sendText(this.name, to, Text);
}
@Override
public void sendImage(String to, String Image) {
System.out.println("对不起您没有发送图片的权限");
}
}
public class client {
public static void main(String[] args) {
abstructChatRoom chatRoom=new ChatRoom();
Member member1=new CommonMember("zlx");
chatRoom.addRoom(member1);
Member member2=new DiamondMember("lj");
chatRoom.addRoom(member2);
Member member3=new CommonMember("tf");
chatRoom.addRoom(member3);
member1.sendText("lj", "hello");
member1.sendImage("ft", "image");
member2.sendText("zlx", "fine");
member3.sendText("zlx", "thank");
member3.sendImage("lj", "image");
}
}
输出结果：
zlx向lj发送的文本：hello
lj接收来自zlx的文本：hello
对不起您没有发送图片的权限
lj向zlx发送的文本：fine
zlx接收来自lj的文本：fine
tf向zlx发送的文本：thank
zlx接收来自tf的文本：thank
对不起您没有发送图片的权限
- 要求：设计一个网上书店，对系统中所有的计算机类图书（ComputerBook）每本都有10%的折扣，语言类图书（LanguageBook）每本都有2元的折扣，小说类图书（NovelBook）每100元有15元的折扣。使用Strategy模式来设计。
类图：
关键类java源码及注释：
public interface BookStrategy {
double calcPrice(double bookPrice);
}
public class ComputerBook implements BookStrategy{
@Override
public double calcPrice(double bookPrice) {
System.out.println("ComputerBook 10% discount. ");
return bookPrice*0.9;
}
}
public class LanguageBook implements BookStrategy{
@Override
public double calcPrice(double bookPrice) {
System.out.println("LanguageBook-2.0 discount.");
return bookPrice-2.0;
}
}
public class NovelBook implements BookStrategy{
@Override
public double calcPrice(double bookPrice) {
System.out.println("NovelBook100.00-15.00");
int bp = (int)bookPrice;
return bookPrice - (double)(bp / 100 * 15);
}
}
public class Price {
private BookStrategy strategy;
public void setStrategy(BookStrategy strategy){
this.strategy=strategy;
}
public double calcPrice(double bookPrice){
return this.strategy.calcPrice(bookPrice);
}
}
public class client {
public static void main(String[] args) {
Price price1=new Price();
BookStrategy strategy1=new ComputerBook();
price1.setStrategy(strategy1);
double p1=123;
System.out.println("计算机类图书原价"+p1+"计算机类图书折扣后:"+price1.calcPrice(p1));
Price price2=new Price();
BookStrategy strategy2=new LanguageBook();
price2.setStrategy(strategy2);
double p2=456;
System.out.println("语言类图书原价"+p2+"语言类图书折扣后:"+price2.calcPrice(p2));
Price price3=new Price();
BookStrategy strategy3=new NovelBook();
price3.setStrategy(strategy3);
double p3=789;
System.out.println("小说类图书"+p3+"小说类图书折扣后:"+price3.calcPrice(p3));
}
}
输出结果：
ComputerBook 10% discount.
计算机类图书原价123.0计算机类图书折扣后:110.7
LanguageBook-2.0 discount.
语言类图书原价456.0语言类图书折扣后:454.0
NovelBook100.00-15.00
小说类图书789.0小说类图书折扣后:684.0
