package com.project.money.oop;

public class SmallChangeSys {
    public static void main(String[] args) {
        SmallChangeSysOOP p=new SmallChangeSysOOP();
        p.menu();
    }
}

SmallChangeSysOOP用來實(shí)現(xiàn)具體功能

代碼如下：

package com.project.money.oop;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Scanner;
public class SmallChangeSysOOP {
    private  double in_money=0;//當(dāng)前流動的錢
    private double balance=0;//余額
    private String detailed="------------零錢通明細(xì)--------------";
    private Date date = null;
    //可以用于日期格式化的
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm");
public void menu(){};
//1 零錢通明細(xì)
 public void detailed_(){};
 //2 收益入賬"
 public void input(){};
 //3消費(fèi)
    public void output(){};

}

具體說明各個方法的作用：

public void menu()方法

public void menu(){//菜單
        boolean loop=true;
        Scanner scanner = new Scanner(System.in);
        while(loop){//循環(huán)展示菜單
            System.out.println("\n============oop零錢通菜單==============");
            System.out.println("\t\t1 零錢通明細(xì)");
            System.out.println("\t\t2 收益入賬");
            System.out.println("\t\t3 消費(fèi)");
            System.out.println("\t\t4 退" + "\t" + "出");
            System.out.print("請選擇1-4:");int key= scanner.nextInt();//選擇；
            switch (key){
                case 1:detailed_();break;
                case 2:input();break;
                case 3:output();break;
                case 4:System.out.println("\t\t程序已經(jīng)退出");loop=false;break;
            }

        }
    }

void detailed_()方法

public void detailed_(){
        System.out.println(detailed);//直接輸出字符
    }

public void input()方法

public void input(){//收益入賬
        Scanner scanner = new Scanner(System.in);
        System.out.println("請輸入金額：");
        this.in_money=scanner.nextDouble();

        while(in_money<0){
            System.out.println("======輸入有誤======");
            System.out.println("是否重新輸入？Y（是）或 N（否） ");//可能點(diǎn)錯了不是輸入
            String in=scanner.next();//是否重新輸入
            if(in.equals("n")||in.equals("N")){
                System.out.println("返回主頁面中....");
                /*****************************************/
                try {
                    Thread.sleep( 1000 );//暫停1秒提升用戶感受
                } catch (Exception e){}
                /*******************************************/
                return;//退出輸入
            }

                System.out.println("請輸入金額：");
                this.in_money=scanner.nextDouble();
        }
        this.balance+=this.in_money;
        String beizhu="";
        date = new Date();
        System.out.println("請輸入備注：");
        beizhu=scanner.next();
        this.detailed+="\n收益入帳\t+" + this.in_money + "\t" + sdf.format(date) +
                "\t余額：" + this.balance+ "  備注：" +beizhu;
    }

**

public void output()方法

**

 public void output(){
        System.out.println("請輸入金額：");
        Scanner scanner = new Scanner(System.in);
        in_money=scanner.nextDouble();
        if(balance<in_money){
            System.out.println("余額不足，請充值");
            return;
        }
        while(in_money<0){
            System.out.println("輸入錯誤，請重輸");
            in_money=scanner.nextDouble();
            if(balance<in_money){
                System.out.println("余額不足，請充值");
                return;
            }
        }
        this.balance-=in_money;
        System.out.println("請輸入備注：");
        String beizhu=scanner.next();
        this.detailed+="\n余額支出\t-" + this.in_money + "\t" + sdf.format(date) +
                "\t余額：" + this.balance+ "  備注：" +beizhu;

    }

SmallChangeSysOOP完整代碼

package com.project.money.oop;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Scanner;
public class SmallChangeSysOOP {
    private  double in_money=0;//當(dāng)前流動的錢
    private double balance=0;//余額
    private String detailed="------------零錢通明細(xì)--------------";
    private Date date = null;
    //可以用于日期格式化的
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm");

    public void menu(){//菜單
        boolean loop=true;
        Scanner scanner = new Scanner(System.in);
        while(loop){//循環(huán)展示菜單
            System.out.println("\n============oop零錢通菜單==============");
            System.out.println("\t\t1 零錢通明細(xì)");
            System.out.println("\t\t2 收益入賬");
            System.out.println("\t\t3 消費(fèi)");
            System.out.println("\t\t4 退" + "\t" + "出");
            System.out.print("請選擇1-4:");int key= scanner.nextInt();//選擇；
            switch (key){
                case 1:detailed_();break;
                case 2:input();break;
                case 3:output();break;
                case 4:System.out.println("\t\t程序已經(jīng)退出");loop=false;break;
            }

        }
    }
    //1 零錢通明細(xì)
    public void detailed_(){
        System.out.println(detailed);
    }
    //2 收益入賬"
    public void input(){//收益入賬
        Scanner scanner = new Scanner(System.in);
        System.out.println("請輸入金額：");
        this.in_money=scanner.nextDouble();

        while(in_money<0){
            System.out.println("======輸入有誤======");
            System.out.println("是否重新輸入？Y（是）或 N（否） ");//可能點(diǎn)錯了不是輸入
            String in=scanner.next();//是否重新輸入
            if(in.equals("n")||in.equals("N")){
                System.out.println("返回主頁面中....");
                /*****************************************/
                try {
                    Thread.sleep( 1000 );//暫停1秒提升用戶感受
                } catch (Exception e){}
                /*******************************************/
                return;//退出輸入
            }

                System.out.println("請輸入金額：");
                this.in_money=scanner.nextDouble();
        }
        this.balance+=this.in_money;
        String beizhu="";
        date = new Date();
        System.out.println("請輸入備注：");
        beizhu=scanner.next();
        this.detailed+="\n收益入帳\t+" + this.in_money + "\t" + sdf.format(date) +
                "\t余額：" + this.balance+ "  備注：" +beizhu;
    }
    //3消費(fèi)
    public void output(){
        System.out.println("請輸入金額：");
        Scanner scanner = new Scanner(System.in);
        in_money=scanner.nextDouble();
        if(balance<in_money){
            System.out.println("余額不足，請充值");
            return;
        }
        while(in_money<0){
            System.out.println("輸入錯誤，請重輸");
            in_money=scanner.nextDouble();
            if(balance<in_money){
                System.out.println("余額不足，請充值");
                return;
            }
        }
        this.balance-=in_money;
        System.out.println("請輸入備注：");
        String beizhu=scanner.next();
        this.detailed+="\n余額支出\t-" + this.in_money + "\t" + sdf.format(date) +
                "\t余額：" + this.balance+ "  備注：" +beizhu;

    }


}