我的笔记 食品管理

import java.util.*; public class guangli {     public static void main(String[] args)throws Exception     {         Spgl aa=new Spgl();         Scanner in=new Scanner(System.in);         try         {             while(true)             {                 System.out.println("请按下方提示进行操作");                 System.out.println("添加食品请输入1");                 System.out.println("查找食品信息请输入2");                 System.out.println("修改食品价格请输入3");                 System.out.println("删除食品请输入4");                 System.out.println("退出系统请输入0");                 String  number=in.next();                 if(number.equals("1"))                 {                     System.out.println("请输入食品的编号");                     String bh=in.next();                     System.out.println("请输入食品名称");                     String mc=in.next();                     System.out.println("请输入食品的价格");                     float jg=in.nextFloat();                     Sp sp=new Sp(bh,mc,jg);                     aa.addSp(sp);                 }                 else if(number.equals("2"))                 {                     System.out.println("请输入食品的编号");                     String bianhao=in.next();                     aa.Spxx(bianhao);                 }                 else if(number.equals("3"))                 {                     System.out.println("请输入食品编号");                     String bianhao=in.next();                     System.out.println("请输入食品价格");                     float jiage=in.nextFloat();                     aa.Spxg(bianhao,jiage);                 }                 else if(number.equals("4"))                 {                     System.out.println("请输入要删除的食品编号");                     String bianhao=in.next();                     aa.Sprm(bianhao);                 }                 else if(number.equals("0"))                 {                     System.out.println("感谢您的使用");                     System.exit(0);                 }                 else                 {                     System.out.println("输入有误");                 }             }         }catch(Exception e)         {             System.out.println("输入有误");         }     } } class Sp {     private String bianhao;     private String name;     private float jiage;     public String getBianhao() {         return bianhao;     }     public void setBianhao(String bianhao) {         this.bianhao = bianhao;     }     public String getName() {         return name;     }     public void setName(String name) {         this.name = name;     }     public float getJiage() {         return jiage;     }     public void setJiage(float jiage) {         this.jiage = jiage;     }     Sp(String bianhao,String name,float jiage)     {         this.bianhao=bianhao;         this.name=name;         this.jiage=jiage;     } } class Spgl {     private ArrayList A=null;     Spgl()     {         A=new ArrayList();     }     public void addSp(Sp sp)     {         A.add(sp);         System.out.println("添加食品成功");     }     public void Spxx(String bianhao)     {         int i=0;         for(i=0;i<A.size();i++)         {             Sp b=(Sp)A.get(i);             String bh=b.getBianhao();             if(bh.equals(bianhao))             {                 System.out.println("食品的编号为:"+bh);                 System.out.println("食品名称为:"+b.getName());                 System.out.println("食品价格为:"+b.getJiage());                 break;             }         }         if(i==A.size())         {             System.out.println("输入有误查无此物");         }     }     public void Spxg(String bianhao,float jiage)     {         int i=0;         for( i=0;i<A.size();i++)         {             Sp b=(Sp)A.get(i);             if(b.getBianhao().equals(bianhao))             {                 b.setJiage(jiage);                 System.out.println("修改成功");                 break;             }         }         if(i==A.size())         {             System.out.println("输入有误查无此物");         }     }     public void Sprm(String bianhao)     {         int i=0;         for(i=0;i<A.size();i++)         {             Sp b=(Sp)A.get(i);             if(b.getBianhao().equals(bianhao))             {                 A.remove(i);                 break;             }         }         if(i==A.size())         {             System.out.println("输入有误查无此物");         }     } }