Java：面積，圓周率，重載，對(duì)象數(shù)組，商品管理系統(tǒng)，登錄，查詢所有和單個(gè)，修改商品
//一、在Shape類中添加計(jì)算面積的重載并調(diào)用。
//重載1：double（正方形面積）
//重載2：double,double（長方形面積）
//重載3：int,double(圓形面積)
package a;
public class Shape {
public static void main(String[] args) {
Shape changfangxing = new Shape();
changfangxing.chang = 1;
changfangxing.kuan = 3;
Shape zhengfangxing = new Shape();
zhengfangxing.lengchang = 2;
Shape yuanxing = new Shape();
yuanxing.banjing = 3;
// jx.setKuan(11);
//
// jx.setChang(2);
int changfangxingzhouchang = changfangxing.changfangxingzhouchang();
int changfangxingmianji = changfangxing.changfangxingmianji();
double yuanxingmianji = yuanxing.yuanxingmianji();
double yuanxingzhouchang = yuanxing.yuanxingzhouchang();
int zhengfangxingmianji = zhengfangxing.zhengfangxingmianji();
int zhengfangxingzhouchang = zhengfangxing.zhenfangxingzhouchang();
System.out.println("長方形周長為" + changfangxingzhouchang + ",長方形面積"
+ changfangxingmianji);
System.out.println("正方形周長為" + zhengfangxingzhouchang + ",正方形面積"
+ zhengfangxingmianji);
System.out.println("圓形周長為" + yuanxingzhouchang + ",圓形面積"
+ yuanxingmianji);
}
private int banjing;
private int chang;
private int kuan;
private int lengchang;
public int changfangxingmianji() {
return (this.kuan * this.chang);
}
public int changfangxingzhouchang() {
return ((this.kuan + this.chang) * 2);
}
public int getBanjing() {
return banjing;
}
public int getChang() {
return chang;
}
public int getKuan() {
return kuan;
}
public int getLegnchang() {
return lengchang;
}
public void setbanjing(int banjing) {
this.banjing = banjing;
}
public void setBanjing(int banjing) {
this.banjing = banjing;
}
public void setChang(int chang) {
this.chang = chang;
}
public void setKuan(int kuan) {
this.kuan = kuan;
}
public void setLegnchang(int legnchang) {
this.lengchang = legnchang;
}
public void setlengchang(int lengchang) {
this.lengchang = lengchang;
}
public double yuanxingmianji() {
return (this.banjing * this.banjing * (Math.PI));
}
public double yuanxingzhouchang() {
return (this.banjing * 2 * (Math.PI));
}
public int zhenfangxingzhouchang() {
return (this.lengchang * 4);
}
public int zhengfangxingmianji() {
return (this.lengchang * this.lengchang);
}
}
//二、使用對(duì)象數(shù)組制作商品管理系統(tǒng)：
//1.用戶登錄
//2.查詢所有商品
//3.查詢單個(gè)商品
//4.修改商品信息
//思路:
//? 1.商品管理系統(tǒng)是不是首先要有商品，是不是，所以 我們要先聲明商品類（商品編號(hào)，名稱，價(jià)格）。方法:介紹 商品，我們就使用toString()進(jìn)行介紹,記得在構(gòu)造方法中對(duì) 屬性進(jìn)行賦值，并設(shè)置get/set方法,商品類完畢
//? 2.用戶登錄，所以我們還要有個(gè)用戶類，用戶包含用 戶名和密碼兩個(gè)屬性，因?yàn)橹灰容^用戶輸入的用戶名和秘密 是否一致只是獲取，所以只設(shè)置其get方法即可,用戶類完畢
//? 3.制作登錄功能,登錄的時(shí)候提示用戶輸入用戶名和 密碼，輸入錯(cuò)誤提示用戶名或密碼錯(cuò)誤，正確就到商品的主界 面
//? 4.查詢所有商品的功能,既然要查詢商品，查詢那些 商品呢?是不是要有一個(gè)容器來存儲(chǔ)商品，所以我們定義一個(gè) 對(duì)象數(shù)組來存儲(chǔ)商品
//? 5.查詢所有商品，其實(shí)就是將商品的容器里的內(nèi)容進(jìn) 行遍歷出來,那么我們寫一個(gè)for循環(huán)將其內(nèi)容遍歷一下就可以 啦
//? 6.根據(jù)編號(hào)查詢單個(gè)商品，首先要提示用戶輸入一個(gè)商品編號(hào)，進(jìn)行比較一下對(duì)象數(shù)組中有沒有這個(gè)編號(hào)，有就打印其信息，沒有就打印商品不存在
//? boolean b=true;//b默認(rèn)使true，如果查到這個(gè)商品b就使false,如果商品遍歷完畢b還是true，說明該商品不存在
//? 7.修改商品的操作,首先要提示用戶要修改那個(gè)商品，所以第一步要提示用戶輸入一個(gè)商品編號(hào)，接收到編號(hào)后還是要比較一下這個(gè)商品存不存在，如何比較，參照步驟6，
//接收完畢后將接收到的內(nèi)容賦值給該商品就完成啦！
package a;
import java.util.Scanner;
public class fuxi {
public static void main(String[] args) {
shangpin[] sp = { new shangpin("1", "詩書畫唱限量周邊", 99),
new shangpin("2", "詩書畫唱牌限量機(jī)器人", 9999),
new shangpin("3", "詩書畫唱教程", 999),
new shangpin("4", "詩書畫唱限量CD", 999),
new shangpin("5", "《詩書畫唱自傳》", 99) };
Scanner s = new Scanner(System.in);
yonghu y = new yonghu();
while (true) {
System.out.println("歡迎來到詩書畫唱商品管理系統(tǒng)");
System.out.println("請(qǐng)登錄！先點(diǎn)贊!先投幣！先收藏！先三連!先關(guān)注！");
System.out.println("請(qǐng)輸入用戶名:");
String uname = s.next();
System.out.println("請(qǐng)輸入密碼:");
String pwd = s.next();
if (y.getUname().equals(uname) && y.getPwd().equals(pwd)) {
break;
} else {
System.out.println("用戶名或密碼輸入錯(cuò)誤,請(qǐng)重新輸入！點(diǎn)個(gè)贊！點(diǎn)個(gè)關(guān)注！");
}
}
System.out.println("登錄成功!");
while (true) {
System.out.println("請(qǐng)輸入你要執(zhí)行的操作:1.查詢所有商品2. 根據(jù)編號(hào)查詢單個(gè)商品3.修改商品信息 ");
int nums = s.nextInt();
if (nums == 1) {
for (int i = 0; i < sp.length; i++) {
System.out.println(sp[i].toString());
}
} else if (nums == 2) {
System.out.println("請(qǐng)輸入你要查詢的商品編號(hào)");
String snum = s.next();
boolean b = true;
for (int i = 0; i < sp.length; i++) {
if (sp[i].getBianhao().equals(snum)) {
System.out.println(sp[i].toString());
b = false;
}
}
if (b) {
System.out.println("商品不存在，三連?。?#34;);
}
}
else if (nums == 3) {
System.out.println("請(qǐng)輸入你要修改的商品編號(hào)");
String bianhao = s.next();
boolean b = true;
for (int i = 0; i < sp.length; i++) {
if (sp[i].getBianhao().equals(bianhao)) {
System.out.println("請(qǐng)輸入該商品的新名稱");
String newname = s.next();
System.out.println("請(qǐng)輸入該商品的新價(jià)格，點(diǎn)贊！");
double newprice = s.nextDouble();
sp[i].setName(newname);
sp[i].setPrice(newprice);
b = false;
}
}
if (b) {
System.out.println("商品不存在，點(diǎn)贊！");
}
} else {
System.out.println("輸入錯(cuò)誤，投幣！");
}
}
}
}
class shangpin {
private String bianhao;
private String name;
private double price;
public shangpin(String bianhao, String name, double price) {
this.bianhao = bianhao;
this.name = name;
this.price = price;
}
public String getBianhao() {
return bianhao;
}
public String getName() {
return name;
}
public double getPrice() {
return price;
}
public void setBianhao(String bianhao) {
this.bianhao = bianhao;
}
public void setName(String name) {
this.name = name;
}
public void setPrice(double price) {
this.price = price;
}
@Override
public String toString() {
return "商品編號(hào)：" + bianhao + ",商品名稱：" + name + ",商品價(jià)格：" + price;
}
}
class yonghu {
private String pwd = "222";
private String uname = "111";
public String getPwd() {
return pwd;
}
public String getUname() {
return uname;
}
public void setPwd(String pwd) {
this.pwd = pwd;
}
public void setUname(String uname) {
this.uname = uname;
}
}
